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Effects of dietary fat and fiber on plasma and urine androgens and estrogens in men: A controlled feeding study

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We conducted a controlled feeding study to evaluate the effects of fat and fiber consumption on plasma and urine sex hormones in men. The study had a crossover design and included 43 healthy men aged 19-56 y. Men were initially randomly assigned to either a low-fat, high-fiber or high-fat, low-fiber diet for 10 wk and after a 2-wk washout period crossed over to the other diet. The energy content of diets was varied to maintain constant body weight but averaged approximately 13.3 MJ (3170 kcal)/d on both diets. The low-fat diet provided 18.8% of energy from fat with a ratio of polyunsaturated to saturated fat (P:S) of 1.3, whereas the high-fat diet provided 41.0% of energy from fat with a P:S of 0.6. Total dietary fiber consumption from the low- and high-fat diets averaged 4.6 and 2.0 g.MJ-1.d-1, respectively. Mean plasma concentrations of total and sex-hormone-binding-globulin (SHBG)-bound testosterone were 13% and 15% higher, respectively, on the high-fat, low-fiber diet and the difference from the low-fat, high-fiber diet was significant for the SHBG-bound fraction (P = 0.04). Men's daily urinary excretion of testosterone also was 13% higher with the high-fat, low-fiber diet than with the low-fat, high-fiber diet (P = 0.01). Conversely, their urinary excretion of estradiol and estrone and their 2-hydroxy metabolites were 12-28% lower with the high-fat, low-fiber diet (P < or = 0.01). Results of this study suggest that diet may alter endogenous sex hormone metabolism in men.
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Am J Clin Nutr 1996;64:850-5. Printed in USA. © 1996 American Society for Clinical Nutrition
Effects of dietary fat and fiber on plasma and urine
androgens and estrogens in men: a controlled feeding
Joanne F Dorgan, Joseph T Judd, Christopher Longcope, Charles Brown, Arthur Schatzkin,
Beverly A Clevidence, William S Campbell, Padmanabhan P Nair, Charlene Franz, Lisa Kahie, and
Philip R Taylor
ABSTRACT We conducted a controlled feeding study to
evaluate the effects of fat and fiber consumption on plasma and
urine sex hormones in men. The study had a crossover design and
included 43 healthy men aged 19-56 y. Men were initially ran-
domly assigned to either a low-fat, high-fiber or high-fat, low-fiber
diet for 10 wk and after a 2-wk washout period crossed over to the
other diet. The energy content of diets was varied to maintain
constant body weight but averaged 13.3 MJ (3170 kcal)/d on
both diets. The low-fat diet provided 18.8% of energy from fat
with a ratio of polyunsaturated to saturated fat (P:S) of 1.3,
whereas the high-fat diet provided 41.0% of energy from fat with
a P:S of 0.6. Total dietary fiber consumption from the low- and
high-fat diets averaged 4.6 and 2.0 g - MJ - d ‘, respectively.
Mean plasma concentrations of total and sex-hormone-binding-
globulin (SHBG)-bound testosterone were 13% and 15% higher,
respectively, on the high-fat, low-fiber diet and the difference from
the low-fat, high-fiber diet was significant for the SHBG-bound
fraction (P = 0.04). Men’s daily urinary excretion of testosterone
also was 13% higher with the high-fat, low-fiber diet than with the
low-fat, high-fiber diet (P = 0.01). Conversely, their urinary
excretion of estradiol and estrone and their 2-hydroxy metabolites
were 12-28% lower with the high-fat, low-fiber diet (P 0.01).
Results of this study suggest that diet may alter endogenous sex
hormone metabolism in men. Am J Cliii Nutr l996;64:
850-5.
KEY WORDS Diet, dietary fats, dietary fiber, estrogen,
androgens
INTRODUCTION
Diet, particularly fat consumption, has been implicated as a
risk factor for prostate cancer. Prostate cancer mortality is
higher in countries where per capita consumption of animal fat
is elevated (1), and high-fat diets have been associated with an
increased risk of prostate cancer in several case-control and
cohort studies (2-9). In the Health Professionals Follow-up
Study, a prospective study of 51 529 men, the relative risk for
advanced prostate cancer was 1.79 (95% CI = 1.04, 3.07) for
those in the highest compared with the lowest quintile of fat
intake, and the association was primarily due to animal fat
consumption (8).
Prostate cancer is a hormone-dependent cancer and a
current hypothesis is that diet modifies prostate cancer risk
through an effect on the sex hormones (10, 1 1). Male
vegetarians have been reported to have lower plasma testos-
terone and estradiol concentrations than omnivores (1 2), and
dietary fat and fiber have been correlated with sex hormone
concentrations in several studies (12-14). Specific diet-
hormone relations reported in men include positive correla-
tions of testosterone with polyunsaturated fat (13) and di-
hydrotestosterone with vegetable fat consumption (14) and
inverse correlations of testosterone and estradiol with fiber
intake (1 2). However, comparisons between vegetarians and
omnivores and correlations of specific dietary components
with hormones from different studies have been inconsistent
(12-17). Moreover, in three diet intervention studies (18-
20), serum or urine testosterone levels were depressed with
the low-fat, high-fiber or vegetarian diet, but findings for
other hormones were inconsistent.
In 1986 the National Cancer Institute and Beltsville Human
Nutrition Research Center, Agriculture Research Service, con-
ducted a controlled feeding study in men to evaluate the effect
of modifying dietary fat and fiber intakes on several indexes
potentially related to cancer or atherosclerosis, including
plasma lipoproteins (21), prostaglandins (22), fecal mutagens,
and hormones. As part of this study, we evaluated the effect of
these dietary components on plasma and urine androgens and
estrogens.
1 From the Division of Cancer Prevention and Control, National
Cancer Institute, Bethesda, MD; the Diet and Human Performance
Laboratory, Beltsville Human Nutrition Research Center, ARS, US
Department of Agriculture, Beltsville, MD; the Departments of Obstet-
rics and Gynecology and Medicine, University of Massachusetts Mcd-
ical School, Worcester, MA; and Information Management Services,
Inc, Silver Spring, MD.
2 Address reprint requests to IF Dorgan, CPSA, DCPC, National Cancer
Institute, Executive Plaza North, Room 211, 6130 Executive Boulevard,
Bethesda, MD 20892-7326. E-mail: dorganj@dcpeepn.nci.nih.gov.
Received February 15, 1996.
Accepted for publication July 25, 1996.
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DIET AND ENDOGENOUS SEX HORMONES
851
SUBJECTS AND METHODS
Healthy male volunteers aged 19-56 y from the Beltsville,
MD, area who met the following criteria were recruited for the
controlled feeding study in 1986: 1) no history of diabetes,
cancer, or cardiovascular, kidney, or chronic gastrointestinal
disease; 2) no medication use other than an occasional analge-
sic; 3) a weight-for-height 80-130% of the desirable value
based on 1983 Metropolitan Life Insurance tables (23); 4)
normal results from a physical examination, including a com-
plete blood count and biochemical profile; and 5) no adherence
to a vegetarian diet in the past year. The research with human
volunteers was approved by the Institutional Review Boards of
Georgetown University and the National Cancer Institute. In-
formed consent was obtained from all men before enrollment.
The high-fat, low-fiber diet was designed to provide “‘40%
of energy from fat, with a ratio of polyunsaturated to saturated
fat (P:S) of 0.5, and 2.0 g total dietary fiber/Mi. The low-fat,
high-fiber diet was designed to provide < 20% of energy from
fat, a P:S of 1.2, and 4.6 g total dietary fiberfMJ. For both diets,
approximately one-third of the fiber was to come from each of
the fruit and vegetable, cereal, and legume groups. The study
used a crossover design. Participants were paired by age,
smoking status, and body mass index, and one man from each
pair was randomly assigned to each diet. After 10 wk on the
diet and a 2-wk washout period, participants were crossed over
to the other diet for 10 wk.
All meals were prepared in the Human Study Facility at the
Beltsville Human Nutrition Research Center. On weekdays
subjects ate breakfast and dinner in the dining room at this
facility and lunches were provided at breakfast for consump-
tion later in the day at work or at home. On weekends subjects
ate prepackaged meals at home. No foods other than those
provided by the study were permitted except tea and coffee.
Sweeteners and other additives to these beverages were limited
to those provided by the study, and quantities used were
recorded by participants. Salt was allowed ad libitum and
consumption was estimated by using tared salt shakers. Water
of known mineral content was provided to participants. Alco-
hol and vitamin and mineral supplements were prohibited.
Men were weighed on each weekday and the energy content
of the diets was varied in l.7-MJ (400-kcal) increments to
maintain constant body weight. Diets provided all known nu-
trients in amounts to meet recommended dietary allowances
(24). Nutrient composition was calculated by using US Depart-
ment of Agriculture (USDA) food-composition data together
with data from the food industry, the Nutrition Coordinating
Center at the University of Minnesota, and analyzed values. A
7-d menu cycle was used and composites of each menu were
analyzed to confirm the nutrient composition.
Blood was collected between 0600 and 0900 after a 12-h fast
on 1 d during the last week of each diet phase of the controlled
diet study. A 24-h urine sample was also collected on every day
of the final week and aliquots proportional to the total daily
volume from each day were pooled to create a single urine
specimen for each dietary period. Urine was collected on ice
and kept cold until measured and apportioned for storage. All
plasma and urine specimens were stored at - 80 #{176}Cor lower
until shipped to the laboratory on dry ice for hormone analyses,
which were performed between 1988 and 1989.
Testosterone, dihydrotestosterone, estrone, and estradiob
in plasma were measured by radioimmunoassay after sob-
vent extraction and celite chromatography (25). Androstan-
ediol glucuronide was measured by radioimmunoassay as
described by Horton et al (26-28). Dehydroepiandrosterone
sulfate (DHEAS) was measured with a radioimmunoassay
kit (ICN-Biomedical, Costa Mesa, CA) and SHBG was
measured with an immunoradiometric assay kit (Farmos
Group Ltd, Oulunsalo, Finland). The percentages of un-
bound and albumin-bound testosterone and estradiol were
measured by using centrifugal ultrafiltration (29, 30), and
percentages of SHBG-bound hormones were calculated.
Urinary testosterone glucuronide was measured with a ra-
dioimmunoassay kit (ICN-Biomedical) and our results were
similar to those reported for normal males by Doberne and
New (3 1 ) and Tresguerres et al (32) after hydrolysis with
-glucuronidase. The urinary estrogens were measured by
radioimmunoassay after 3-glucuronidase hydrolysis (33)
and LH-20 sephadex chromatography (Pharmacia LKB Bio-
technology, Piscataway, NJ) as described (34). Urinary
2-hydroxyestrone and 2-hydroxyestradiol were measured by
radioimmunoassay according to the methods of Chattoraj et
al (35).
For each analyte, plasma and urine samples from the same
man were analyzed in the same batch to remove the effects of
between-batch variability in hormone assays. Within-batch
CVs of plasma hormone measurements in replicate quality-
control samples averaged 8.2% for estrone, 5.7% for estradiol,
11.8% for testosterone, 13.7% for dihydrotestosterone, and
8.9% for DHEAS. The within-batch CV for the percentage free
and albumin-bound estradiol and testosterone were all < 10%
except for free estradiol, which was 10.8%. In urine the within-
batch CV for glucuronides averaged 16.0% for estrone, 6.8%
for estradiob, 20.8% for estriol, and 9.2% for testosterone. For
the catechols, the within-batch CV averaged 9.4% for 2-hy-
droxyestrone and 12.0% for 2-hydroxyestradiol.
Because distributions of plasma and urine hormones were
not normal, geometric means were used to describe the data.
Methods proposed by Fleiss (36) were used to evaluate
carryover and diet effects. To determine whether carryover
from period 1 to period 2 was the same regardless of initial
diet, for each hormone the sum of levels from both periods
for men initially randomly assigned to the high-fat, low-
fiber diet were compared with the sum for men initially
randomly assigned to the low-fat, high-fiber diet by using a
Wilcoxon rank-sum test. Because there was no evidence of
differential carryover for any hormone at a significance
level of 0.10, carryover was ignored when the effect of
diet was evaluated. The diet effect was estimated by the
difference between hormone levels after the high-fat, low-
fiber and low-fat, high-fiber diets regardless of diet order.
The significance of the diet effect was tested by comparing
the difference in hormone levels between periods 1 and 2 for
men initially randomly assigned to the high-fat, low-fiber
diet with the same difference for men initially randomly
assigned to the low-fat, high-fiber diet using a t test if the
distribution of differences was normally distributed and a
Wilcoxon rank-sum test otherwise. All analyses were per-
formed by using SAS statistical software (37).
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DORGAN ET AL
I Ratio of polyunsaturated to saturated fat.
RESULTS
DISCUSSION
Of the 45 men randomly assigned to the controlled diet
study, 43 completed both phases. Their mean SD) age was
33.8 ± 9.2 y and their median body weights at baseline and at
the end of the controlled feeding study, respectively, were 79.6
kg (range: 58.2-122.2 kg) and 79.0 kg (range: 60.2-1 15.8 kg),
which were not significantly different. Seven (16%) of the men
were black and 10 (23%) smoked cigarettes.
The nutrient composition of the actual diets consumed dur-
ing each study period is shown in Table 1. Energy intake was
= 13.3 MJ (3 170 kcal)/d on both the high-fat, low-fiber and
low-fat, high-fiber diets. The median daily percentage of en-
ergy from fat was 41.0% (range: 38.6-42.0%) with the high-fat
diet and 18.8% (range: 17.4-20.5%) with the low-fat diet. Type
of fat also differed between diets; the median P:S was 0.6
(range: 0.5-0.7) for the high-fat diet compared with 1 .3 (range:
1.0-1.6) for the low-fat diet. Total dietary fiber intake from the
low-fat diet was more than twice that from the high-fat diet.
Hormones in plasma and urine specimens collected at the
end of each period of the controlled diet study and differences
between the high-fat, low-fiber and low-fat, high-fiber diets are
shown in Tables 2 and 3. Plasma concentrations of androgens
tended to be elevated with the high-fat, low-fiber diet; geomet-
ric mean concentrations of total and SHBG-bound testosterone
were 13% and 15% higher, respectively, compared with the
bow-fat, high-fiber diet and for SHBG-bound testosterone the
mean difference was significant (P = 0.04). Men’s daily cx-
cretion of testosterone glucuronide was also 13% higher when
the high-fat, low-fiber diet was consumed than when the bow-
fat, high-fiber diet was consumed, and the mean difference was
significant (P = 0.01). We also evaluated the effect of diet on
the ratio of dihydrotestosterone to testosterone in plasma and
found that the ratio was essentially unchanged after the low-fat,
high-fiber diet compared with that after the high-fat, low-fiber
diet; the mean difference was -0.01 (95% CI = -0.02, 0.01).
Trends were inconsistent for the plasma estrogens, and none
of the differences examined were significant. However, men’s
excretion of glucuronides of estradiol and estrone and their
2-hydroxy metabolites were all 12-28% bower after the high-
fat, low-fiber diet (P 0.01).
In this controlled feeding study plasma androgens in a single
blood draw tended to be elevated when men ate a high-fat,
low-fiber compared with a low-fat, high-fiber diet for 10 wk.
With the high-fat, low-fiber diet, amounts of testosterone glu-
curomde were also greater and estradiob and estrone glucu-
ronide amounts were bower in 24-h urine samples collected
over 1 wk and pooled.
Howie and Shultz (12) reported lower plasma testosterone
and estradiol concentrations in male vegetarians than in meat
eaters, but the majority of studies that compared plasma an-
drogens and estrogens in vegetarians and omnivores did not
detect differences (13, 15-17). Vegetarians were reported to
have elevated SHBG concentrations in two studies (13, 16),
and in one (16) the ratio of testosterone to SHBG was de-
pressed, suggesting that vegetarians may have less non-SHBG-
bound, or bioavailabbe, testosterone compared with omnivores.
In the study by Howie and Shultz (12), plasma testosterone and
estradiol concentrations were inversely correlated with dietary
fiber ingestion. Key et al (13) on the other hand found positive
correlations of testosterone with polyunsaturated fat intake and
SHBG with total, saturated, and polyunsaturated fat intakes.
Twenty-four-hour excretions of the androgens DHEAS, an-
drosterone, and etiocholanobone, and the estrogens estradiol,
estrone, and estriol were significantly lower in middle-aged
South African blacks, who customarily follow a vegetarian diet
compared with North American blacks eating meat (18). When
the North Americans were fed a diet without any meat or meat
products, their 24-h urine excretion of androgens and estrogens
decreased significantly, and when the South Africans were
switched to a Western diet including meat, their urine output of
these hormones increased. Diet-hormone relations were age-
dependent, however, and when South African blacks aged
60 y ate meat, their urine estrogens and androgens and serum
androgens were lower than when they consumed a vegetarian
diet (18, 38).
Because vegetarians could differ from omnivores on char-
acteristics other than diet that influence hormone concentra-
tions, Raben et al (20) investigated the effect of consuming a
vegetarian diet on serum hormones in a controlled study. Eight
men were fed a lactoovovegetarian diet and a mixed-meat diet
TABLE 1
Medians and ranges of daily nutrient consumption by diet
High-fat, low-fiber diet
Low-fat, high-fiber diet
Median Range Median Range
Energy (MJ) 13.2
10.2-18.5
13.3 10.0-18.5
Protein(%ofenergy)
14.8
13.0-18.1 17.1
16.0-17.9
Carbohydrate (% of energy)
45.3
43.6-48.8 67.5 66.0-68.7
Total fat (% of energy) 41.0 38.6-42.0
18.8 17.4-20.5
Saturated fat (% of energy) 14.7
13.9-15.4
4.4 3.7-5.2
Linoleic acid (% of energy) 8.1 6.6-8.8
5.3 4.1-6.3
Oleic acid (% of energy)
14.1
12.1-16.1
6.4 5.5-7.4
P:S’ 0.6
0.5-0.7 1.3 1.0-1.6
Cholesterol (mgIMJ)
45.1 44.1-46.3
18.2 17.5-18.6
Total dietary fiber (g/MJ)
2.0 2.0-2.0
4.6 4.6-4.6
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DIET AND ENDOGENOUS SEX HORMONES 853
TABLE 2
Geometric mean (95% CI) concentrations and mean (95% CI) differences in plasma sex-hormone-binding globulin (SHBG), androgens, and estrogens
by diet
High-fat , low-fiber diet Low-fat, high-fiber diet High-fat diet - low-fat diet
Mean 95% CI Mean 95% CI Difference’
95% CI P
SHBG (nmol/L) 19.2 16.9, 21.6 18.5 16.2, 21.2 1.2
-0.6, 2.9 0.33
Androgens
Testosterone (nmolIL)
Total 13.3
11.6, 15.3 11.8 10.1, 13.8 1.6 -0.2,3.5 0.10
Free 0.31 0.26, 0.36 0.33 0.23, 0.28
0.03 -0.02, 0.08 0.27
Albumin-bound 4.4 3.8, 5.2 4.1 3.4, 4.9 0.4 -0.4, 1.1 0.37
SHBG-bound 8.2 7.0, 9.7
7.1 6.0, 8.5 1.2 0.1, 2.4 0.04
Dihydrotestosterone (nmolIL) 1.2
1.1, 1.4 1.1 0.9, 1.3 0.09
-0.04, 0.22 0.20
DHEAS (mol/L) 9.3 8.2, 10.5 8.8 7.6, 10.1
0.4 -0.6, 1.4 0.10
Androstanediol glucuronide (nmoLfL) 1.7 1.5, 1.9 1.7 1.5, 1.9 0.1 -0.1, 0.2 0.99
Estrogens
Estrone (pmolIL)
154.1 140.3, 170.0 148.0 133.8, 164.7 4.8 -6.3, 16.0 0.28
Estradiol (pmol/L)
Total 99.4 87.9, 112.6 104.6 90.9, 120.3 -6.8 -18.7,5.0 0.31
Free 2.2 2.0, 2.5 2.4 2.1, 2.8 -0.3 -0.6, 0.1 0.15
Albumin-bound
32.9 28.8, 37.4 36.3 30.7, 42.7 - 1.7 -6.1, 2.3 0.12
SHBG-bound 63.4 55.7, 72.2 64.9 56.5, 74.1 -2.9 - 10.3, 4.4 0.46
Mean differences of untransformed values after removal of outliers: total estradiol (n 1), free estradiol (n I), albumin-bound estradiol (n 3).
DHEAS, dehydroepiandrosterone sulfate.
2 p value for test of H0: difference = 0 when using all observations based on a t test when differences were normally distributed (total, free,
albumin-bound, and SHBG-bound testosterone; dihydrotestosterone; and SHBG-bound estradiol) and a Wilcoxon rank-sum test when differences were not
normally distributed (SHBG, DHEAS, androstanediol glucuronide, estrone, and total, free, and albumin-bound estradiol).
each for 6 wk. The diets were isoenergetic and “‘28% of
energy was derived from fat on both diets. The P:S, however,
was > 1 with the vegetarian diet compared with “0.5 with the
meat diet and the fiber content of the vegetarian diet was
approximately twice that of the meat diet. Predict serum con-
centrations of testosterone were comparable and decreased
significantly by 35% after the vegetarian diet but not after the
meat diet. Differences in other androgens and estrogens were
also reported, but these were attributed to dissimilarities in
baseline concentrations.
Hamabainen et al (19) studied the effect of modifying dietary
fat on serum sex hormones in 30 healthy, free-living men
40-49-y old. Serum sex hormones were measured after a 2-wk
period when men consumed their usual diets, which provided
40% of energy as fat with a P:S of 0.15 and again after a 6-wk
intervention period when men consumed isoenergetic diets that
provided 25% of energy as fat with a P:S of 1.22. After the
intervention, men had significantly lower serum concentrations
of androstenedione and total and free testosterone. However,
concentrations of dihydrotestosterone, DHEAS, estradiol, and
estrone did not differ between the two periods.
Reed (39) failed to detect a difference in total testosterone in
six men following isoenergetic diets providing 20 and 100 g
fat/cl. Because SHBG concentrations increased, however, free
testosterone decreased after the low-fat diet.
Our finding of greater daily urine testosterone excretion in
men consuming a high-fat, low-fiber diet relative to men con-
suming a low-fat, high-fiber diet is consistent with the findings
of most controlled feeding studies. We also observed elevated
plasma testosterone concentrations when men ate the high-fat,
low-fiber diet, but the difference from concentrations in men
who consumed the low-fat, high-fiber diet was significant only
TABLE 3
Geometric mean (95% CI) amounts and mean (95% CI) differences in daily urine hormones by diet
High-fat , low-fiber diet Low-fat,
high-fiber diet High- fat diet - low-fat diet
Mean 95% Cl
Difference’ 95% CI P
Mean 95% CI
Glucuronides
Testosterone (nmol/d) 161.3 124.6, 207.4 143.0
1 12.5, 180.8 26.1 9.6, 42.6 0.01
Estrone (nmol/d) 1 1.1 9.8, 12.6 13.8 12.3, 15.6 -2.4 -3.4, - 1.3 0.0002
Estradiol (nmolld) 3.8 3.4, 4.3 4.3 3.7, 4.9 -0.6 - 1.0, -0.2
0.008
Estriol (nmol/d) 6.8 5.5, 8.3 6.8 5.5, 8.4 0.3 -0.7, 1.4 0.57
Catechols
2-hydroxyestrone (nmol/d) 71.8 65.1, 78.6
85.2 76.4, 94.1 - 14.6 -21.6, -7.5 0.0003
2-hydroxyestradiol (nmolld)
9.3 8.1, 10.7 12.9 11.5, 14.4
-3.4 -4.8, -2.0 <0.0001
I Mean differences of untransformed values after removal of outliers: testosterone (n = 2), estrone (n 1), estriol (n 1).
2 p value for test of H0: difference = 0 when using all observations based on a I test when differences were normally distributed (estradiol,
2-hydroxyestrone, 2-hydroxyestradiol) and a Wilcoxon rank-sum test when differences were not normally distributed (testosterone, estrone, and estriol).
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DORGAN ET AL
for the fraction that was SHBG-bound. The lack of significance
for plasma total testosterone may have been due to within-
person variation in hormone concentrations. Plasma testoster-
one has been reported to exhibit considerable diurnal variation,
falling 42% from morning until night in one study (40). Fur-
thermore, because of short-term fluctuations in blood concen-
trations, Goldzieher et al (41) estimated that a testosterone
value from a single blood draw would be within 20% of the
underlying mean only 68% of the time. Testosterone amounts
in 24-h urine specimens collected over 1 wk and pooled,
therefore, are probably a more valid assessment than are con-
centrations in a single-morning blood draw collected after an
overnight fast.
We observed lower daily urine estradiol and estrone glu-
curonide excretion in men after consumption of a high-fat,
low-fiber diet. Hill et al ( 18) also reported lower urine
estrogens in South African black men aged 60 y who ate
a diet with meat rather than their usual vegetarian diet. In
younger men aged < 55 y, the opposite effect was observed,
indicating that age modified the relation of diet and urine
hormones. The men in our study were 19-56 y of age; when
we analyzed the data separately for those aged 30 y and
for those aged > 30 y, both groups had lower urine estro-
gens after consuming the high-fat, low-fiber diet.
Because the major source of estrogen in men is the pe-
ripheral aromatization of androgens, our finding of an in-
crease in urinary excretion of testosterone but a slight de-
crease in the excretion of estrone and estradiol after a
high-fat low-fiber diet was unexpected. However, it is pos-
sible that this was a result of a decrease in the peripheral
aromatization of androgens that offset the slight increase in
androgen amounts. Although peripheral aromatization of
androgens is influenced by body weight (42), the men’s
weight was stable throughout the study. No data are avail-
able on the effect of dietary fat and fiber on peripheral
aromatization.
The major urinary metabolites of estradiol are the
catechols (2-hydroxyestradiol and 2-hydroxyestrone) and
16a-hydroxyestrone. Although controversial (43), 16a-hy-
droxyestrone has been implicated in mammary carcinogen-
esis (44) and could potentially play a robe at different sites.
We observed decreased excretion of catechol estrogens after
a high-fat, low-fiber diet. Although we did not measure
urinary 16a-hydroxyestrone, we did measure estriol, which
was unaffected by diet in our study. Among women, Long-
cope et al (45) found that consumption of a high-fat diet
resulted in decreased excretion of catechol estrogens and
significantly increased excretion of l6a-hydroxyestrone
and its metabolite estriol. Adlercreutz et al (43), however,
reported no difference in urinary of 2-hydroxyestrone be-
tween omnivorous and vegetarian women, although their
dietary fat and fiber intakes differed significantly. Addi-
tional studies are needed to clarify whether discrepancies in
the effects of dietary fat and fiber on the pathways of
estrogen metabolism reflect a sex difference and/or are due
to differences in study design.
In summary, results of this controlled feeding study suggest
that dietary fat and fiber may affect sex hormone metabolism in
men in a way that may influence prostate cancer risk. CI
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... All studies accounted for the diurnal rhythms of sex hormones, by ensuring the time of the blood sample was the same for each study condition. 2 studies used serum measurements [45,46], and 4 studies used plasma measurements [44,[47][48][49], with different hormonal assays used across the studies. Therefore, to minimise differences due to blood samples and assays, standardised mean differences with 95 % CIs were used for all outcomes. ...
... HF = 39.6), or 580 kcal (LF = 547, HF = 1127). 3 studies directly measured and reported TEI [45,46,48], the weighted mean difference for LF vs HF diets was -49 kcal/day (LF = 2877, HF = 2926). 4 studies reported bodyweight [44][45][46]48], the weighted mean change in bodyweight during the dietary interventions was -0.8 kg. ...
... 3 studies directly measured and reported TEI [45,46,48], the weighted mean difference for LF vs HF diets was -49 kcal/day (LF = 2877, HF = 2926). 4 studies reported bodyweight [44][45][46]48], the weighted mean change in bodyweight during the dietary interventions was -0.8 kg. ...
Article
Background: Higher endogenous testosterone levels are associated with reduced chronic disease risk and mortality. Since the mid-20th century, there have been significant changes in dietary patterns, and men’s testosterone levels have declined in western countries. Cross-sectional studies show inconsistent associations between fat intake and testosterone in men. Methods: Studies eligible for inclusion were intervention studies, with minimal confounding variables, comparing the effect of low-fat vs high-fat diets on men’s sex hormones. 9 databases were searched from their inception to October 2020, yielding 6 eligible studies, with a total of 206 participants. Random effects meta-analyses were performed using Cochrane’s Review Manager software. Cochrane’s risk of bias tool was used for quality assessment. Results: There were significant decreases in sex hormones on low-fat vs high-fat diets. Standardised mean differences with 95% confidence intervals (CI) for outcomes were: total testosterone [-0.38 (95% CI -0.75 to -0.01) P = 0.04]; free testosterone [-0.37 (95% CI -0.63 to -0.11) P = 0.005]; urinary testosterone [-0.38 (CI 95% -0.66 to -0.09) P = 0.009]; and dihydrotestosterone [-0.3 (CI 95% -0.56 to -0.03) P = 0.03]. There were no significant differences for luteinising hormone or sex hormone binding globulin. Subgroup analysis for total testosterone, European and North American men, showed a stronger effect [-0.52 (95% CI -0.75 to -0.3) P < 0.001]. Conclusions: Low-fat diets appear to decrease testosterone levels in men, but further randomised controlled trials are needed to confirm this effect. Men with European ancestry may experience a greater decrease in testosterone, in response to a low-fat diet.
... All studies accounted for the diurnal rhythms of sex hormones, by ensuring the time of the blood sample was the same for each study condition. 2 studies used serum measurements [45,46], and 4 studies used plasma measurements [44,[47][48][49], with different hormonal assays used across the studies. Therefore, to minimise differences due to blood samples and assays, standardised mean differences with 95% CIs were used for all outcomes. ...
... HF = 39.6), or 580kcal (LF = 547, HF = 1127). 3 studies directly measured and reported TEI [45,46,48], the weighted mean difference for LF vs HF diets was -49 kcal/day (LF = 2877, HF = 2926). 4 studies reported bodyweight [44][45][46]48], the weighted mean change in bodyweight during the dietary interventions was -0.8kg. ...
... 3 studies directly measured and reported TEI [45,46,48], the weighted mean difference for LF vs HF diets was -49 kcal/day (LF = 2877, HF = 2926). 4 studies reported bodyweight [44][45][46]48], the weighted mean change in bodyweight during the dietary interventions was -0.8kg. ...
Preprint
Full-text available
Background: Higher endogenous testosterone levels are associated with reduced chronic disease risk and mortality. Since the mid-20th century, there have been significant changes in dietary patterns, and men's testosterone levels have declined in western countries. Cross-sectional studies show inconsistent associations between fat intake and testosterone in men. Methods: Studies eligible for inclusion were intervention studies, with minimal confounding variables, comparing the effect of low-fat vs high-fat diets on men's sex hormones. 9 databases were searched from their inception to October 2020, yielding 6 eligible studies, with a total of 206 participants. Random effects meta-analyses were performed using Cochrane's Review Manager software. Cochrane's risk of bias tool was used for quality assessment. Results: There were significant decreases in sex hormones on low-fat vs high-fat diets. Standardised mean differences with 95% confidence intervals (CI) for outcomes were: total testosterone [-0.38 (95% CI -0.75 to -0.01) P = 0.04]; free testosterone [-0.37 (95% CI -0.63 to -0.11) P = 0.005]; urinary testosterone [-0.38 (CI 95% -0.66 to -0.09) P = 0.009], and dihydrotestosterone [-0.3 (CI 95% -0.56 to -0.03) P = 0.03]. There were no significant differences for luteinising hormone or sex hormone binding globulin. Subgroup analysis for total testosterone, European and American men, showed a stronger effect [-0.52 (95% CI -0.75 to -0.3) P < 0.001]. Conclusions: Low-fat diets appear to decrease testosterone levels in men, but further randomised controlled trials are needed to confirm this effect. Men with European ancestry may experience a greater decrease in testosterone, in response to a low-fat diet.
... Wang et al. precisely calculated that a reduction in dietary fat intake (and increase in fiber) resulted in 12% lower circulating androgen levels without changing the clearance [41]. A symmetrical effect was reported by Dorgan et al. [42], who observed an increase in serum and urinary T levels during a high-fat, low-fiber diet in healthy men [42]. According to Mai et al., free fatty acids (FFAs) increase the synthesis of androgen precursors (DHEA and androstenedione) in vivo in men [43]. ...
... Wang et al. precisely calculated that a reduction in dietary fat intake (and increase in fiber) resulted in 12% lower circulating androgen levels without changing the clearance [41]. A symmetrical effect was reported by Dorgan et al. [42], who observed an increase in serum and urinary T levels during a high-fat, low-fiber diet in healthy men [42]. According to Mai et al., free fatty acids (FFAs) increase the synthesis of androgen precursors (DHEA and androstenedione) in vivo in men [43]. ...
Article
Full-text available
The roles of dietary macronutrients and physical activity (PA) in patients with PCOS have not been sufficiently reported, especially in adolescent girls. To address this knowledge gap, we evaluated the associations between serum concentrations of total testosterone (tT), free testosterone (fT), androstenedione (A), dehydroepiandrosterone-sulfate (DHEA-S), sex hormone-binding globulin (SHBG) and dietary macronutrients intake as well as different types and levels of PA. The study population consisted of 96 girls of Caucasian ancestry, aged 14-18 years: 61 participants with polycystic ovary syndrome (PCOS) and 35 healthy controls. Serum tT, fT, A, DHEA-S, and SHBG were determined in fasting blood. Macronutrient intake and PA levels were assessed by using the three-day food record method and the Beliefs and Eating Habits Questionnaire (KomPAN), respectively. We found several positive correlations between dietary macronutrients such as total fat, saturated fatty acids (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA), and hormonal parameters across the entire cohort and in healthy girls. A positive correlation between SHBG and total protein consumption as well as an inverse correlation between SHBG and carbohydrate intake could be determined. No correlation between androgens and macronutrients was found in the PCOS group. In contrast, we observed an inverse correlation between androgen concentrations (except of DHEA-S) and "work/school" and/or "leisure time" PA only in PCOS patients. Moreover, the hormone levels differed according to PA intensity. In conclusion, the impact of diet and PA was strikingly different in adolescents with and without PCOS. These findings indicate that disturbed hormonal homeostasis in PCOS, at least in the youngest patients, likely "overtrump" dietary influences, and otherwise, PA offers a therapeutic potential that requires further evaluation of the long-term effects in randomized studies. (ClinicalTrial.gov Identifier: NCT04738409.) Citation: Mizgier, M.; Watrowski, R.; Opydo-Szymaczek, J.; Jodłowska-Siewert, E.; Lombardi, G.; Kędzia, W.; Jarząbek-Bielecka, G.
... fruit, vegetables, whole-grain products, legumes, and nuts), may be connected with better semen quality (22)(23)(24)(25)(26)(27). In contrast, in other studies, a beneficial influence of pro-healthy dietary patterns on the quality of semen was not observed (28,29), and results on associations between dietary fiber intake and hormone levels affecting the male reproductive system were inconsistent (30)(31)(32)(33)(34). These inconsistent results may be down to the effect of the presence of pesticide residues, heavy metals and nitrate in fruit and vegetables, substances that can cause the generation of ROS, and have a proven negative impact on sperm quality (3,(35)(36)(37). ...
... Increased dietary fiber consumption also positively impacts the gut microbiome, which plays a key role in the immune system's function and reduces the concentration of pro-inflammatory mediators such as IL-6 and CRP (59,60). However, the effect of dietary fiber consumption on estrogen and testosterone concentration is not fully understood (30)(31)(32)(33)(34). FIGURE 3 | Semen quality parameters by quartiles (Q) of fruit and vegetable consumption. ...
Article
Full-text available
The influence of fruit and vegetable consumption on semen quality by reducing oxidative stress is inconsistent. Thus, the association between the consumption of these products, antioxidant status, and semen quality was investigated in 90 men aged 18–40. The consumption of fruit and vegetables was collected using the 3-day food record method. Antioxidant status: total antioxidant capacity in semen (TAC-s) and blood (TAC-b), blood superoxide dismutase (SOD-b), glutathione reductase (GR-b), glutathione peroxidase (GPx-b), catalase (CAT-b) activity, and malondialdehyde concentration in blood (MDA-b) were measured. Sperm concentration, leukocytes in the ejaculate, vitality, motility, and sperm morphology were examined using computer-aided semen analysis (CASA). The consumption of fruit and vegetables was positively correlated with sperm concentration, vitality, motility, TAC-s, TAC-b, and SOD-b activity. The TAC-s and TAC-b were positively related to motility, TAC-s was inversely correlated with sperm tail defects. The SOD-b activity was positively correlated with vitality, motility, sperm morphology, and inversely with sperm tail defects and leukocytes in the ejaculate. Compared to the men in the first quartile of fruit and vegetable consumption (<318 g/day), those in the highest quartile (>734 g/day) had the highest sperm concentration, vitality, motility, TAC-s, TAC-b, GPx-b activity, and the lowest MDA-b concentration (based on multivariate regression models). A high consumption of fruit and vegetables may positively influence selected sperm quality parameters by improving the antioxidant status of semen and blood.
... This depends on the athlete's training state and goals. For example, higher-fat diets appear to maintain circulating testosterone concentrations better than low-fat diets (Reed et al., 1987;Hamalainen et al., 1983;Dorgan et al., 1996) [32,11,7] . This has relevance to the documented testosterone suppression which can occur during volume-type overtraining (Fry et al., 1998) [9] . ...
... This depends on the athlete's training state and goals. For example, higher-fat diets appear to maintain circulating testosterone concentrations better than low-fat diets (Reed et al., 1987;Hamalainen et al., 1983;Dorgan et al., 1996) [32,11,7] . This has relevance to the documented testosterone suppression which can occur during volume-type overtraining (Fry et al., 1998) [9] . ...
Article
Full-text available
Sportsperson required a proper balanced diet to full fill the daily need of nutrients. Absence of nutrients and their presence in lesser amounts in the sportsperson diet affects the performance of sportsperson. Many researchers found that the diet rich in nutrients and intake of sports drinks enhance the sportsperson performance. Sports drinks are to prompt fast fluid absorption and speed up rehydration and promote recovery after the exercise. Macronutrients plays an important role in our diet, carbohydrates gives energy supply for cell functions, fat also providing energy for workout, and principle elements of cell membranes and facilitation of the absorption of fat-soluble vitamins. Protein helps rebuild and repair muscle after exercise and also a source of energy during exercise, particularly when carbohydrate reserves are very low. 1. Introduction Sports nutrition is a part of nutrition in which study of nutrients and their role in sports person diet and the study of the human body and exercise science (Congeni and Miller, 2002) [19]. Sports Nutrition is also defined as the application of nutrition knowledge to a practical daily eating plan providing the fuel for physical activity, facilitating the repair and building process following hard physical work and achieve athletic performance in various competitive events, while also promoting overall health and wellness (Prochaska and Velicer, 1997) [31]. Sports Nutrition applies nutrition principles to sport with the intent of maximizing performance. Success in sports depends on three factors-genetic endowments, the state of training and nutrition. Genetic make-up cannot be changed. Specialized exercise training is the major means to improve athletic performance and proper nutrition is an important component of the total training program. Athletes and fitness enthusiasts need the same essential nutrients that non-active people need with varied increases in their caloric needs as well as some increase in macro and micronutrients. Therefore, it is essential to explore and assess these increased nutritional needs of athletes before, during, and after event for achieving optimal sports performance. The human body obtains nutrients from the digestion and absorption of food, and they are needed for virtually all bodily functions. Macronutrient (i.e., carbohydrates, fats and proteins) provide energy, the micronutrients (i.e., vitamins and minerals) are required for a number of specific metabolic functions. A balanced diet must supply all nutrients to fulfill the requirements for energy and the other elements that support metabolism, including water. The individual requirement for each nutrient differ and it depends on age, gender, presence of medical conditions and level of physical activity (NRC, 2002) [26]. The information about the nutrition playing an important role in sports performance. Many aspects can impact the performance of a sports person during championship which may be related to different domains. The most frequently encountered nutritional related problem among sports person is their failure to eat up sufficient total of food energy. Food is composed of six basic substances: minerals, fats, vitamins, proteins carbohydrates and water. Each one of these has specific function in providing nourishment for the body. The body requires these nutrients to function properly however the body is unable to endogenously manufacture them in the quantities needed on a daily basis (Weber, 2004) [38] .
... However, a few studies conducted on males have shown that dietary fiber either has some beneficial effect on testosterone secretion and semen quality or no effect at all. Dorgan et al. (1996) found that plasma total testosterone and sex hormone-binding globulin levels were 13 and 15% higher, respectively, in the high-fat and low-fiber groups than in the low-fat and high-fiber groups in healthy men. Moreover, men with low-fat and high-fiber intake were reported to have reduced serum and urine androgen levels (Wang et al., 2005). ...
Article
Full-text available
Although fiber-rich diets have been positively associated with sperm quality, there have not been any studies that have examined the effects of dietary fiber and its metabolites on sperm quality in young or pre-pubescent animals. In this study, we aimed to explore the effect of dietary fiber supplementation on semen quality and the underlying mechanisms in a boar model. Sixty purebred Yorkshire weaning boars were randomly divided into the four groups (T1–T4). Groups T1, T2, and T3 boars were fed diets with different levels of fiber until reaching 160 days of age and were then fed the same diet, while group T4 boars were fed a basal diet supplemented with butyrate and probiotics. Compared with T1 boars, sperm motility and effective sperm number were significantly higher among T3 boars. Meanwhile, at 240 days of age, the acetic acid and total short-chain fatty acid (SCFA) contents in the sera of T3 and T4 boars were significantly higher than those in T1 boars. The abundance of microbiota in T2 and T3 boars was significantly higher than that in T1 boars ( P < 0.01). Moreover, dietary fiber supplementation increased “beneficial gut microbes” such as UCG-005, Rumenococcus, Rikenellaceae_RC9_gut_group and Lactobacillus and decreased the relative abundance of “harmful microbes” such as Clostridium_sensu_stricto_1, Romboutsia and Turicibacter . Collectively, the findings of this study indicate that dietary fiber supplementation improves gut microbiota and promotes SCFA production, thereby enhancing spermatogenesis and semen quality. Moreover, the effects of dietary fiber are superior to those of derived metabolites.
... Although GSPE administration reduced testosterone in L18 at ZT15 in CAFfed rats, the rhythm was not recovered. In this sense, changes in testosterone levels by exposure to different photoperiods and by diet composition have been reported [65][66][67], a fact in agreement with our results showing a photoperiod-dependent variation and an increase by CAF diet. Moreover, as discussed above, the bioavailability of GSPE is different according to the photoperiod [47], modulating in a photoperiod-dependent manner the effect on the levels of this hormone. ...
Article
Full-text available
Variations in the light/dark cycle and obesogenic diets trigger physiological and behavioral disorders. Proanthocyanidins, in addition to their healthy properties, have recently demonstrated a modulating effect on biological rhythms. Therefore, the aim of this study was to evaluate the administration of a grape seed proanthocyanidin-rich extract (GSPE) to mitigate the disruption caused by a sudden photoperiod change in healthy and cafeteria (CAF)-diet obese rats. For this, 48 photoperiod-sensitive Fischer 344 rats were fed standard or CAF diets for 6 weeks under a standard (12 h light/day, L12) conditions. Then, rats were switched to a long (18 h light/day, L18) or short (6 h light/day, L6) photoperiod and administered vehicle or GSPE (25 mg/kg) for 1 week. Body weight (BW) and food intake (FI) were recorded weekly. Animal activity and serum hormone concentrations were studied before and after the photoperiod change. Hormone levels were measured both at 3 h (ZT3) and 15 h (ZT15) after the onset of light. Results showed the impact of the CAF diet and photoperiod on the BW, FI, activity, and hormonal status of the animals. GSPE administration resulted in an attenuation of the changes produced by the photoperiod disruption. Specifically, GSPE in L6 CAF-fed rats reduced serum corticosterone concentration, restoring its circadian rhythm, increased the T3-to-T4 ratio, and increased light phase activity, while under L18, it decreased BW and testosterone concentration and increased the animal activity. These results suggest that GSPE may contribute to the adaptation to the new photoperiods. However, further studies are needed to elucidate the metabolic pathways and processes involved in these events.
... Aesthetic athletes, for example, are required to undergo CR periods in their respective pre-competitive phases to achieve the desired physique. Some authors have observed that diets with a low fat intake (≤20% FAT) can reduce testosterone levels [106,108]. Nevertheless, it is difficult to extract a direct association of these two variables due to other characteristics of the trials; in addition to a low fat intake, the subjects undergoing CR had a low percentage of body fat and a low intake of saturated fat and polyunsaturated fatty acids [4,107,[109][110][111]. If, to establish the energy deficit, it is decided to reduce the contribution of FAT, the recommendation is to ensure an intake of 20-30% of the total daily energy supply or, if that is not possible due to the caloric limitation and to prioritization of an adequate intake of PRO and CHO, a daily FAT intake of at least 0.5 g/kg BW should be ensured [77]. ...
Article
Full-text available
Managing the body composition of athletes is a common practice in the field of sports nutrition. The loss of body weight (BW) in resistance-trained athletes is mainly conducted for aesthetic reasons (bodybuilding) or performance (powerlifting or weightlifting). The aim of this review is to provide dietary–nutritional strategies for the loss of fat mass in resistance-trained athletes. During the weight loss phase, the goal is to reduce the fat mass by maximizing the retention of fat-free mass. In this narrative review, the scientific literature is evaluated, and dietary–nutritional and supplementation recommendations for the weight loss phase of resistance-trained athletes are provided. Caloric intake should be set based on a target BW loss of 0.5–1.0%/week to maximize fat-free mass retention. Protein intake (2.2–3.0 g/kgBW/day) should be distributed throughout the day (3–6 meals), ensuring in each meal an adequate amount of protein (0.40–0.55 g/kgBW/meal) and including a meal within 2–3 h before and after training. Carbohydrate intake should be adapted to the level of activity of the athlete in order to training performance (2–5 g/kgBW/day). Caffeine (3–6 mg/kgBW/day) and creatine monohydrate (0.08–0.10 g/kgBW/day) could be incorporated into the athlete’s diet due to their ergogenic effects in relation to resistance training. The intake of micronutrients complexes should be limited to special situations in which there is a real deficiency, and the athlete cannot consume through their diet.
... This depends on the athlete's training state and goals. For example, higher-fat diets appear to maintain circulating testosterone concentrations better than low-fat diets [27][28][29] . This has relevance to the documented testosterone suppression which can occur during volume-type overtraining 30 . ...
Chapter
Benign prostatic hyperplasia (BPH) is common among older men. The androgen pathway is implicated in its development, which involves increased stromal growth in the periurethral areas of the prostate. Modifiable risk factors for BPH include obesity and diet, and nonmodifiable risk factors include age and family history. It appears as though a diet rich in vegetables, plant-based proteins, and fiber and low in starches, such as bread, pasta, and rice, lowers the risk of BPH. To a lesser extent, a diet low in fat and increased intake of zinc, flaxseed, and fluted pumpkin seeds appear to reduce the risk as well. Low-fat and high-fiber diets as well as an increased intake of zinc, flaxseed, and fluted pumpkin seeds may halt the progression of and potentially reverse BPH. Overall, the dietary and physical activity patterns that prevent and reduce features of metabolic syndrome are associated with a decreased risk of BPH.
Article
A population-based case-control study in Utah of 358 cases diagnosed with prostate cancer between 1984 and 1985, and 679 controls categorically matched by age and county of residence, were interviewed to investigate the association between dietary intake of energy (kcal), fat, protein, vitamin A, -carotene, vitamin C, zinc, cadmium, selenium, and prostate cancer. Dietary data were ascertained using a quantitative food-frequency questionnaire. Data were analyzed separately by age (45–67, 68–74) and by tumor aggressiveness. The most significant associations were seen for older males and aggressive tumors. Dietary fat was the strongest risk factor for these males, with an odds ratio (OR) of 2.9 (95 percent confidence interval [CI] 1.0–8.4) for total fat; OR=2.2 (CI=0.7–6.6) for saturated fat; OR=3.6 (CI=1.3–9.7) for monounsaturated fat; and OR=2.7 (CI=1.1–6.8) for polyunsaturated fat. Protein and carbohydrates had positive but nonsignificant associations. Energy intake had an OR of 2.5 (CI=1.0–6.5). In these older men, no effects were seen for dietary cholesterol, body mass, or physical activity. There was little association between prostate cancer and dietary intake of zinc, cadmium, selenium, vitamin C, and -carotene. Total vitamin A had a slight positive association with all prostate cancer (OR=1.6, CI=0.9–2.4), but not with aggressive tumors. No associations were found in younger males, with the exception of physical activity which showed active males to be at an increased but nonsignificant risk for aggressive tumors (OR=2.0, CI=0.8–5.2) and -carotene which showed a nonsignificant protective effect (OR=0.6, CI=0.3–1.6). The findings suggest that dietary intake, especially fats, may increase risk of aggressive prostate tumors in older males.
Article
Several experimental studies have suggested that diet can alter the production and metabolism of steroids in men. The purpose of this study was to determine the levels of unconjugated steroids and steroid glucuronides as well as sex hormone-binding globulin (SHBG) among normal adult men who were either omnivorous or vegetarians. The participants were white volunteers ranging from 25–35 years of age and the blood samples were taken between 0900 h and 1000 h and between 1600 h and 1700 h for two consecutive days. No significant statistical change was found in plasma dehydroepiandrosterone, dehydroepiandrosterone sulfate, testosterone, dihydrotestosterone and estradiol levels. Vegetarian group showed a higher levels of sex hormone-binding globulin (SHBG) while the free androgen index (FAI; calculated by the ratio testosterone/SHBG) was lower in this group. Although the concentrations of androsterone glucuronide were higher in vegetarian group, the vegetarians had a 25–50% lower level of androstane-3α,17β-diol glucuronide and androstane-3β,17β-diol glucuronide. Our data further indicate that both, androstane-3α,17β-diol glucuronide and androstane-3β,17β-diol glucuronide concentrations are significantly correlated with SHBG levels and with the FAI values. The increases in androstane-3α,17β-diol glucuronide and androstane-3β,17β-diol glucuronide levels in the omnivorous group are probably a consequence of the elevation of the FAI. Our data suggest that in a vegetarian group, less testosterone is available for androgenic action.
Article
A radioimmunoassay method for urinary catechol estrogens is described; The specific nature of the antisera allows direct analyses of acid hydrolyzed urine. A LH-20 Sephadex column chromatography can be employed for individual determinations of 2-hydroxyestrone and 2-hydroxyestradiol. The excretion of catechol estrogens during menstrual cycles ranged from 14.48 to 50.15 microgram per 24 hours, whereas, during the last trimester of pregnancies, the values ranged from 129.30 to 1758. 20 microgram per 24 hours.
Article
A simple, reliable and rapid radioimmunoassay (RIA) for the determination of testosterone glucosiduronate (TG) in crude urine is described. Two protein-TG complexes were investigated in raising antibodies: a) Bovine serum albumin (BSA)-TG and b) human plasma Cohn's fraction IV-4 (CF)-TG. In rabbits, high titers of antibodies were obtained after the injection of CF-TG. The specificity of the antiserum was sufficiently high (cross reaction with free testosterone 27%, with 5alpha-dihydrotestosterone-glucosiduronate 20%). TG was estimated in small aliquots of male and female urine after evaporation overnight at 50 degrees C in order to eliminate interfering material. The intraassay coefficient of variation (CV) was found to be 6% and the interassay CV 11%. TB has been determined in 40 samples of urine simultaneously by "direct" RIA and by a "classical" RIA following hydrolysis with beta-glucuronidase. The coefficient of correlation was found to be 0.89. The mean excretion of TG in the urine of 26 healthy men amounted to 164+/-51 mug/24 hours with a range from 97 to 346 mug/24 hours. In a group of 16 women a mean urinary excretion of TG of 24+/-10 mug/24 hours was determined. The method allows a technician to assay 40 samples per day.
Article
A rapid and relatively simple, but specific, radioimmunoassay for the potent androgen, androstanediol (3 alpha-diol), is described. Despite the availability of a nonspecific C-19 androgen antibody requiring a 17 beta-hydroxy group, androstanediol can be measured in plasma by prior purification of a plasma solvent extract using a Celite microcolumn. Values obtained do not differ from those previously reported using more complicated chromatographic techniques.
Article
When plasma hormone levels undergo rapid and large oscillations, as in the case of testosterone, FSH, and LH, a single random sample is likely to yield a result within +/-20% of the true mean value only 68%, 54%, and 30% of the time, respectively. Multiple sampling increases reliability, and computer analysis demonstrates that three equally-spaced samples taken at 6 to 18 min intervals provide the optimum schedule, given certain practical considerations. Pooling of the three plasma samples prior to radioimmunoassay avoids an increased laboratory workload.
Article
Using a rabbit antisera directed against estriol-3-0-carboxy methyl ether complexed to BSA, an immunoassay for estriol (1) was developed. The mean plus or minus SE concentration of estriol in 18 women in days 5-7 of their cycle was 7.9 plus or minus 0.6 pg/ml which was significantly (P less than 0.01) less than the mean value of 11.1 plus or minus 0.8 pg/ml in 15 women in days 20-22 of the cycle. In 3 of 6 women in whom plasma samples were drawn frequently during their cycle, an estriol peak occurred coincident with the estradiol peak. In 3 women from whom plasma was obtained several times during the course of a day estriol levels did not appear to vary significantly. In 8 women who were on oral contraceptives the mean level of estriol was 7.6 plus or minus 1.5 pg/ml. In 8 post-menopausal women the mean level was 6.0 plus or minus 1.2 pg/ml which is significantly (P less than 0.01) less than the mean luteal phase value but not less (P greater than 0.1) than the follicular phase or oral contraceptive user values. We conclude that some of the circulating estriol is directly secreted by the ovary of normal women.
Article
Data are presented on the daily urinary excretion of androstanediol and testosterone in healthy adults using a sensitive radioligand assay. In nine men, the average urinary androstanediol (79 mug/day) was not significantly different from the urinary testosterone (84 mug/day). However, in women the average values of urinary androstanediol excretion (12 mug/day) were significantly higher than the urinary testosterone (4.2 mug/day). In each of the females, the urinary androstanediol was greater than the urinary testosterone. The data do not support the hypothesis that the daily urinary androstanediol excretion is a measure of the 5alpha-reduction of testosterone in androgen target tissues.