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Original Paper
Ann Nutr Metab 1999;43:69–79
Consequences of a Long-Term Raw Food
Diet on Body Weight and Menstruation:
Results of a Questionnaire Survey
C. Koebnick C. Strassner I. Hoffmann C. Leitzmann
Institute of Nutritional Science Justus Liebig University of Giessen, Germany
Received: April 17, 1998
Accepted: January 15, 1999
Dr. Corinna Koebnick
Institute of Nutritional Science, Justus Liebig University of Giessen
Wilhelmstrasse 20, D–35392 Giessen (Germany)
Tel. +49 641 99 39051, Fax +49 641 99 39049
E-Mail Corinna.Koebnick@ernaehrung.uni-giessen.de
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Accessible online at:
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Key Words
Raw food diet W Nutritional deficiency W Body
mass index W Weight loss W Underweight W
Chronic energy deficiency W Amenorrhea
Abstract
Objective:
To examine the relationship be-
tween the strictness of long-term raw food
diets and body weight loss, underweight and
amenorrhea.
Methods:
In a cross-sectional
study 216 men and 297 women consuming
long-term raw food diets (3.7 years; SE 0.25)
of different intensities completed a specially
developed questionnaire. Participants were
divided into 5 groups according to the
amount of raw food in their diet (70–79, 80–
89, 90–94, 95–99 and 100%). A multiple linear
regression model (n = 513) was used to eval-
uate the relationship between body weight
and the amount of raw food consumed. Odds
of underweight were determined by a multi-
nomial logit model.
Results:
From the begin-
ning of the dietary regimen an average
weight loss of 9.9 kg (SE 0.4) for men and
12 kg (SE 0.6) for women was observed. Body
mass index (BMI) was below the normal
weight range (! 18.5 kg/m
2
) in 14.7% of male
and 25.0% of female subjects and was nega-
tively related to the amount of raw food con-
sumed and the duration of the raw food diet.
About 30% of the women under 45 years of
age had partial to complete amenorrhea; sub-
jects eating high amounts of raw food
(1 90%) were affected more frequently than
moderate raw food dieters.
Conclusions:
The
consumption of a raw food diet is associated
with a high loss of body weight. Since many
raw food dieters exhibited underweight and
amenorrhea, a very strict raw food diet can-
not be recommended on a long-term basis.
Introduction
Raw food diets are mainly vegetarian diet
forms based on the experience of physicians
who were highly engaged in healthful nutrition,
such as Bircher-Benner, Waerland and Shel-
70
Ann Nutr Metab 1999;43:69–79
Koebnick/Strassner/Hoffmann/
Leitzmann
Table 1.
Definition of raw food diets
Raw food diets consist predominantly or exclusively of
unheated foods, mainly of plant origin (partly also
of animal origin).
Some foods are included that require a certain degree
of heating for their production (e.g. cold-pressed
honey and cold-pressed oils) as well as foods that
require a certain amount of heat during their pro-
cessing (e.g. dried fruits, dried meat and fish, cer-
tain nuts).
Furthermore, cold-smoked produce (e.g. meat and
fish) as well as pickled or fermented vegetables can
be included in the raw food diet [20, 36].
ton, whose writings constitute the origins of the
main raw food diet streams. Today raw food
diets are influenced mainly by the Diamonds
and are quite varied forms of nutrition, con-
sisting mostly of natural foods prepared in
unheated, non-mixed meals [1–6]. Staple foods
like meat, dairy products, cereals and cereal
products are largely avoided. Therefore, fruits
and vegetables make up a high percentage of
the food consumed and have to meet body
energy needs. A study of the literature shows
that raw food diets are subdivided into vegetar-
ian and non-vegetarian forms.
One of the extreme forms of raw food diets
is instinctotherapy. Its founder, Guy-Claude
Burger [3], recommends eating a.o. non-
heated meat. A few other authors suggest the
consumption of only small amounts of cooked
meat. Because of the large amounts of fruits,
the raw food diet according to Wandmaker [5]
is viewed as unbalanced and is therefore not
recommended by the German Nutrition Soci-
ety [7]. The definition of raw food diets ac-
cording to the Giessen Raw Food Working
Group is an attempt to develop a basis for
comparison of data reported in the literature
(table 1).
The main reasons for practising a raw food
diet as stated by its followers are to attain
health, to prevent illness and to live in a natu-
ral and healthy way for a long time [8, 9].
Some medical reports suggest a raw food diet
as therapy for diseases such as allergies, hy-
pertension and overweight [1, 10–12]. Raw
food diets are mostly considered to be a long-
term form of nutrition. However, the Dia-
monds suggest that their raw food diet can
additionally decrease body weight [2–5, 8].
Almost all persons experience drastic
changes in body weight after starting to con-
sume a raw food diet. The weight loss can be
substantial and often leads to a very low body
weight [8, 9, 13]. Underweight and nutritional
deficiencies in females are related to amenor-
rhea, low bone density and osteoporosis [14–
18]. The aim of the reported study was to
examine the association between the strict-
ness of a raw food diet and body weight loss,
underweight and amenorrhea.
Methods
Subjects
Following announcements in several German
health magazines (October 1992 to January 1993),
1,328 persons classifying themselves as raw food diet-
ers were assessed using a short questionnaire sent by
mail. Of those, 865 persons estimated the amount of
raw food in their diet to be more than 70%. This
amount corresponds to the minimum amount of raw
food recommended by several authors [6]. A specially
developed questionnaire was sent to these selected per-
sons, of whom 88% responded. Individuals practising
a raw food diet for !4 months or being !16 years of
age or not living in Germany, and who had partici-
pated in the pre-test of the questionnaire were ex-
cluded from the study. After this selection 572 persons
remained in the study. Complete data sets were evalu-
ated of 513 persons (216 men and 297 women).
For statistical analyses, participants were divided
into 5 groups according to the amount of raw food in
their diet. The cutoff points were 70, 80, 90, 95, and
100% of raw food. The diet groups were classified as
meat eaters (n = 253), vegetarians (n = 184) and vegans
(n = 135). Vegetarians omit meat and fish, and vegans
additionally avoid dairy products and eggs from their
diet.
BMI before a raw food diet
Consequences of a Long-Term Raw
Food Diet on Body Weight and
Menstruation
Ann Nutr Metab 1999;43:69–79
71
Table 2.
Determinants of BMI:
multiple linear regression
coefficients ordered according
to descending ß (p ! 0.0001,
adjusted R
2
= 0.572)
Independent determinants ßSignificance
0.723 0.000
Amount of raw food consumed, % –0.144 0.000
Duration of raw food diet 0.075 0.016
Vegan diet group –0.068 0.030
Gender 0.053 0.080
Age –0.019 0.566
Total food intake, g 0.006 0.834
Instruments
A short questionnaire was developed as a selection
instrument. It contained a limited number of questions
concerning the amount of raw food consumed and the
duration of the raw food diet. To control the validity of
the self-estimated amounts of raw food consumed, the
results were compared to the computed amounts of a
food frequency questionnaire (FFQ) described below.
There was a high correspondence between the amounts
of raw food consumed [8].
The main questionnaire focused on the nutrition
behavior and the health situation of individuals con-
suming a raw food diet. Body weight data and weight
development were assessed retrospectively. The con-
cept was based on discussions with several authors of
books on raw food diets and interviews of raw food
dieters and their self-help groups. Comprehension of
the questionnaire was tested with a random sample of
16 raw food dieters drawn from the selected partici-
pants that were then excluded from further participa-
tion. Questions which were considered misleading or
unclear were not included in the final instrument.
The amounts of raw food consumed were assessed
by the FFQ developed by Aalderink et al. [19], Hoff-
mann [20] and Hoffmann et al. [21] and employed in
the Giessen Wholesome Nutrition Study. Its validity
as an instrument of selection was tested for bias by
Hoffmann [20]. The semiquantitative FFQ consisted
of 80 items modified for special demands of raw food
diets. The amount of raw food was calculated by the
raw/cooked weight ratio.
Statistics
All statistical calculations were performed with the
statistical software package SPSS 8.0. The results are
presented as means with the standard error of mean
(B SE). Mean body mass index (BMI) values (weight
(kg)/height (m)
2
) were calculated separately for females
and males after adjusting for age at recruitment. The
BMI classification according to Ferro-Luzzi et al. [15]
was employed (table 2). A multiple linear regression
model for BMI as a dependent factor considers age,
gender, BMI before starting a raw food diet, duration
of the raw food diet, diet group and total food intake.
Odds ratios of underweight were computed by a multi-
nomial logit model considering gender and amount of
raw food consumed. Therefore, participants were di-
vided into 5 groups eating different amounts of raw
food: 70–79, 80–89, 90–94, 95–99 and 100%. In the
regression and the logit models of body weight data
only persons with complete data sets were included
(n = 513). Calculations on amenorrhea were carried
out with data from non-pregnant and non-menopausal
women !45 years of age (n = 145). Odds ratios of
amenorrhea were calculated by a multinomial logit
model considering the amount of raw food consumed.
To test the fit the loglinear models were compared to
different models including several factors and several
divisions of the amount of raw food consumed. Only
small differences in parameter estimates were ob-
served [22].
Results
General Health Behavior and Diseases
Most of the raw food dieters investigated
in this study consumed high amounts of raw
food (1 90%; fig. 1). The mean percentage of
raw food eaten was 91 B 0.4%, and the aver-
age duration of a raw food diet was 3.7 B 0.25
years. There were only a few participants who
smoked (2.1%); the raw food dieters con-
sumed only small amounts of alcoholic bever-
ages (beer 13 B 2.6 ml/day; wine 9 B 2.0 ml/
Regular fasting (n = 282)
72
Ann Nutr Metab 1999;43:69–79
Koebnick/Strassner/Hoffmann/
Leitzmann
Fig. 1.
Cumulative frequency distribution of amount
of raw food consumed in male (n = 230) and female
(n = 342) raw food dieters.
Fig. 2.
Error bars of age-adjusted mean BMI B SE
divided into groups according to the amount of raw
food consumed.
20.0
19.0
n= 66
70–79 103
80–89
Amount of raw food consumed (%)
248
90–99 96
100
21.0
BMI (kg/m )
2
22.0
Table 3.
Fasting periods of investi-
gated raw food dieters
%
49.3
Fasting period, days
1 29.8
2–4 27.7
5–7 23.8
8–14 12.4
Several weeks 6.4
day; spirits 0.1 B 0.0 ml/day) and most of
them (89%) participated in various kinds of
physical activities.
Only a few participants (7%) used mineral
or vitamin supplements, 7.9% consumed al-
gae products, and 0.6% of the 342 female par-
ticipants took oral contraceptives. Enemas
were regularly applied by 16.1% of raw food
dieters, about 25% of them more than once a
week. About half of the participants (n = 282)
fasted at least once a year. Total fasting
(48.7%) and juice fasting (39.2%) were pre-
ferred. The main reason for fasting was purifi-
cation (58%). The fasting periods lasted from
1 day to several weeks (table 3).
Most of the participants changed to a raw
food diet for health reasons; other reasons did
not play an important role (!10%). About
55% changed to a raw food diet because of
their own disease, and 17% because of a dis-
ease of a family member. The most important
disorders were diseases of the gut, allergies,
asthma and rheumatism. About 94% of these
participants believed to be closer to recovery
from their disease since change of diet. Most
participants (98%) were very content with
their raw food diet.
Body Weight Reduction and Amount of
Raw Food Consumed
The age-adjusted mean BMI of male par-
ticipants was 20.7 B 0.2 kg/m
2
and of female
participants was 20.1 B 0.1 kg/m
2
. The BMI
range showed a tight distribution (95% CI
20.2–20.6 kg/m
2
). Most participants (73.8%)
Severe underweight (CED grade III)
Consequences of a Long-Term Raw
Food Diet on Body Weight and
Menstruation
Ann Nutr Metab 1999;43:69–79
73
Fig. 3.
Age-adjusted mean BMI be-
fore and during the consumption of
raw food diets.
18 70–79
Groups according to the amount of
raw food consumed (%)
90–99
80–89 100
Before
raw food diet Lowest
level Highest level after
change to raw food diet Present
level
19
20
21
22
23
BMI (kg/m )
2
s
s
s
s
s
Table 4.
Classification of BMI and distribution of relative body weight in relation to gender and amount of raw
food consumed (%)
Classification by Ferro-Luzzi [15] BMI
kg/m
2
Raw food dieters
male female 70–79% 80–89% 90–99% 100%
!16 0.4 1.5 1.3 0.8 0.8 1.9
Moderate underweight (CED grade II) 16.0–16.9 2.2 4.1 2.5 0.8 3.4 6.8
Mild underweight (CED grade I) 17.0–18.4 12.1 19.3 11.4 11.9 17.8 22.3
Normal weight 18.5–24.9 78.3 69.6 69.6 79.4 73.5 67.0
Overweight 25.0–29.9 6.1 3.8 12.7 4.0 4.2 1.0
Obesity 30.0–39.9 0.0 1.2 2.5 0.8 0.4 0.0
Severe obesity 640.0 0.0 0.0 0.0 0.0 0.0 0.0
Missing data 0.9 0.6 0.0 2.4 0.0 1.0
n 230 342 79 126 264 103
had a normal body weight; 6.3% of the men
and 4.8% of the women were overweight;
1.2% of the women and none of the men were
obese. Unexpectedly 14.7% of the men and
25.0% of the women were underweight. Of
these, 2.6% of the men and 5.7% of the wom-
en suffered from chronic energy deficiency
(CED) grade II or III (table 4). Participants
eating a strict raw food diet showed a lower
BMI than persons consuming a moderate raw
food diet (fig. 2). Most raw food dieters expe-
rienced a dramatic loss of body weight after
changing to a raw food diet. Body weight sta-
bilized after some time and settled at a level
below the initial weight (fig. 3). The mean loss
of body weight from the time of changing to a
raw food diet to the time of evaluation was 9.9
B 0.4 kg (95% CI 4–20 kg) for male (n = 216)
and 12 B 0.6 kg (95% CI 3–26 kg) for female
(n = 297) participants. There were substantial
74
Ann Nutr Metab 1999;43:69–79
Koebnick/Strassner/Hoffmann/
Leitzmann
Fig. 4.
Classification of menstruation occurrence in
groups according to the amount of raw food consumed
(n = 145).
Fig. 5.
Error bars of mean BMI B SE in relation to
classification of menstruation occurrence (n = 145).
18.0
19.0
n= 86
Regular 14
Irregular
Classification of menstruation occurrence
45
Amenorrhea
20.0
BMI (kg/m )
2
differences between groups according to the
amount of raw food consumed and loss of
body weight (fig. 3).
The multiple linear regression model (p !
0.0001, adjusted R
2
= 0.572) showed that low
body weight had a strong linear relation
(monotonic decrease) to the amount of raw
food eaten (table 2). The BMI was negatively
affected in the vegan group, but was unaf-
fected by the total food intake. The relations
to gender and duration of raw food diet con-
sumption were statistically significant. Fe-
males showed a lower BMI than males, and
the BMI increased slowly with the duration of
raw food diet consumption. Odds of becom-
ing underweight calculated by a multinomial
logit model (table 5) were 3 times higher for
strict raw food dieters (100% raw food) and 2
times higher for rather strict raw food dieters
(95–99% raw food) than for moderate raw
food dieters (!80% raw food). By including
the diet group in the logit model, no statisti-
cally significant effects were observed. Vegans
had no significantly higher odds of under-
weight than vegetarians or meat eaters.
Amenorrhea as a Functional Problem of
Female Raw Food Dieters
The mean age of non-pregnant and non-
menopausal women under 45 years of age was
32.9 B 0.63 years. Menstruation was stated as
being regular in about 60% of the valid an-
swers. The intensity of menstruation was esti-
mated as strong to very strong by 9.1%, as
medium by 53.3% and as weak to very weak
by 37.7% of the women. Approximately 10%
had irregular menstruation and 30% claimed
to have no or rare menstruation. About 70%
of female participants noticed a change in
menstruation since changing their diet. Of the
female raw food dieters of childbearing age,
23% suffered from a total absence of men-
struation. Female participants were divided
into 3 groups: periodical (n = 87) , irregular
(n = 14), and absence of menstruation (n =
44). The groups show statistically significant
differences in the amounts of raw food con-
sumed (p = 0.008) and in BMI (p = 0.000) but
not in age. Women with partial to total amen-
orrhea ate more raw food and had a lower
BMI than the other women (fig. 4, 5).
Underweight
Amenorrhea
Consequences of a Long-Term Raw
Food Diet on Body Weight and
Menstruation
Ann Nutr Metab 1999;43:69–79
75
Table 5.
Parameter estimates of the multinomial logit model of becoming underweight, goodness-of-fit statistics
and measures of association (reference group: 70–79% amount of raw food)
Factor Odds
ratio
1
Estimate
1
SE z value
2
Asymptotic 95% CI
lower upper
0.1
–2.3329
0.3670 –6.36 –3.05 –1.61
Gender female 2.3
0.8481
0.2331 3.64 0.39 1.31
Raw food consumed
100% 3.0
1.0923
0.3872 2.82 0.33 1.85
95–99% 2.0
0.7016
0.3632 1.96 –0.01 1.41
90–94% 1.2 0.1762 0.4413 0.40 –0.69 1.04
80–89% 0.8 –0.1832 0.4114 –0.45 –0.99 0.62
Goodness-of-fit statistics (likelihood ratio) significance = 0.7686.
Measures of association: entropy = 0.0586, concentration = 0.0626.
1
Odds ratio = e
estimate
.
2
Values statistically significantly different from zero (· = 5%) are given in bold (z value 61.96).
Table 6.
Parameter estimates of the multinomial logit model of having amenorrhea, goodness-of-fit statistics and
measures of association (reference group: 70–79% amount of raw food)
Factor Odds
ratio
1
Estimate SE z value
2
Asymptotic 95% CI
lower upper
0.2 –1.8718 0.7596 –2.46 –3.36 –0.38
Raw food consumed
100% 7.0
1.9408
0.8456 2.30 0.28 3.60
95–99% 2.6 1.0833 0.8209 1.32 –0.53 2.69
90–94% 2.0 0.7087 0.9162 0.77 –1.09 2.50
80–89% 1.8 0.5988 0.8717 0.69 –1.11 2.31
Goodness-of-fit statistics were not calculated due to model saturation.
Measures of association: entropy = 0.0547, concentration = 0.0680.
1
Odds ratio = e
estimate
.
2
Values statistically significantly different from zero (· = 5%) are given in bold (z value 61.96).
Odds of having amenorrhea calculated by
a multinomial logit model (table 6) were 7
times higher for strict raw food dieters (100%
raw food) than for moderate raw food dieters
(!80% raw food). Inclusion of the diet group
in the logit model showed no statistically sig-
nificant relationship between odds of amenor-
rhea and diet group. There were no higher
odds for vegans than for vegetarians or meat
eaters.
76
Ann Nutr Metab 1999;43:69–79
Koebnick/Strassner/Hoffmann/
Leitzmann
Discussion
The consumers of raw food diets view their
eating behavior as part of a wholesome life-
style concept, including an overall healthy
way of life which means more than just an
alternative diet. Adherents of raw food diets
usually lead a healthy life, i.e. they are physi-
cally active, drink little alcohol and do not
smoke. This lifestyle shows a preventative
effect against diseases related to nutrition and
lifestyle [23, 24]. At present, little is known
about the consequences of a raw food diet on
long-term health.
Fasting periods and regular enemas are
often recommended by proponents of raw
food diets as a method of body cleansing [6, 8,
9, 25]. About half of the participating raw
food dieters fasted at least once a year, some
of them for several weeks. It is reported that
very long fasting periods (1100 days) can
result in morphological changes in the cardiac
muscle with ECG changes caused by protein
deficiency [26]. Even though none of the par-
ticipants of the Giessen Raw Food Study
fasted for such a long period of time, fasting
for them could have been a risk because of
their low energy stores and low body weight,
particularly in association with their low ener-
gy diet.
Most proponents of raw food diets recom-
mend this dietary regimen as a long-term diet.
Only the Diamonds advocate their raw food
diet also as a therapy for weight loss [2–5, 8,
25]. The results of the Giessen Raw Food
Study show a substantial reduction in body
weight for participants during long-term con-
sumption of a raw food diet. The body weight
first decreases and then usually increases to a
level below the initial weight. The very conse-
quent raw food dieters show a greater loss of
body weight than the moderate raw food diet-
ers. Change in body weight usually indicates a
change in energy balance and reflects changes
in energy stores and in active body tissues
[27]. Decreasing body weight and concomi-
tant undernutrition result in a greater visceral
mass to muscle mass ratio [28].
The BMI reflects body energy stores and is
used as an indicator for CED [29–32] since it
shows a strong correlation with body fat [27,
33]. Most participants of the Giessen Raw
Food Study had BMI values within the nor-
mal range; however, 25% of the females and
14.7% of the males were below the normal
range – in some cases a BMI reflecting CED
was observed. Undernutrition affects only a
small group of the average German popula-
tion – 5.6% of the females and 3.8% of the
males, mostly under the age of 34 years, are
underweight [34]. The optimum range of BMI
which is compatible with good health is 20.1–
25.0 kg/m
2
for males and 18.7–23.8 kg/m
2
for
females [15, 27]. Low body weight is often
reported for vegetarians and vegans [35], but
a BMI reflecting CED is rarely observed in
contrast to raw food dieters. The main reason
for a low BMI for raw food dieters is the con-
sumption of a strict raw food diet. Further-
more, BMI is correlated with the duration of
the raw food diet and the vegan regimen.
Appleby et al. [36] observed a negative
association between BMI and carbohydrate
intake and the intake of dietary fiber in low
meat eaters. Raw food dieters eat mainly
fruits and vegetables. They mostly omit dairy
products, meat, cereals and cereal products
and therefore, their diet contains high
amounts of dietary fiber and carbohydrates.
Additionally, an insufficient energy supply in
43% of raw food dieters was reported [13, 37].
Very strict raw food dieters have higher odds
of becoming underweight than moderate raw
food dieters. Therefore, a very strict raw food
diet has to be considered as a risk to health if
practised for a long time.
A high percentage of the women (70%) par-
ticipating in the Giessen Raw Food Study had
Consequences of a Long-Term Raw
Food Diet on Body Weight and
Menstruation
Ann Nutr Metab 1999;43:69–79
77
irregularities in their menstruation after
changing to a raw food diet. A total absence of
menstruation was observed in 23% of female
raw food dieters of childbearing age. With
increasing amounts of raw food the BMI de-
creased and the odds of having amenorrhea
increased. The participants judged this as a
success of their diet, since proponents of raw
food diets view menstruation as a process of
cleansing. They claim that eating enough raw
food stops menstruation so that the cleansing
process is no longer required [3, 5, 38]. This
attitude concerning amenorrhea has no scien-
tific basis and ignores the possibility that
amenorrhea may lead to impaired health.
Nutritional deficiencies, low body fat
stores, CED and low body weight which is
related to changes in body composition are
associated with amenorrhea [14, 27, 39–41].
Amenorrhea is also observed with eating dis-
orders like bulimia and anorexia [17, 41–43].
Professional sportswomen often show disor-
dered eating habits, amenorrhea, and osteo-
porosis. This is collectively known as the
female athlete triad [44]. An imbalance be-
tween energy intake and energy expenditure
leads to an energy deficit which is associated
with menstrual irregularities and reproduc-
tive dysfunction in female long distance run-
ners [45].
A low BMI is indicative for CED and is
associated with amenorrhea. Amenorrhea can
result in impaired fertility [16, 27, 42]. When
estrogen levels are low, changes in mineral,
glucose and fat metabolism accompany amen-
orrhea. These metabolic changes affect bone
and cardiovascular health, increasing the risk
of osteoporosis and coronary heart disease in
later life [16, 42]. The maternal BMI is related
to the birth weight of a child [46]. Mothers
from China, India, Ethiopia and Zimbabwe
with a low BMI have babies with low birth
weights [23, 27]. In the female raw food diet-
ers of this study the odds of having amenor-
rhea increased with the strictness of the raw
food diet. For women of childbearing age
there may be further consequences for the
unborn child in case of pregnancy.
The absence of obesity in raw food dieters
should be seen positively, but their extremely
low body weight may be a problem. While an
energy restriction for many adults consuming
an average Western diet is recommended, a
strict raw food diet cannot guarantee an ade-
quate energy supply [20, 37]. A low BMI in
raw food dieters indicates low body energy
stores and CED. In a mostly vegan diet like
the raw food diets with low protein and energy
intake, protein metabolism can be affected to
the point of protein energy malnutrition. The
incidence of amenorrhea in female raw food
dieters is also a sign for functional problems
in the long-term consumption of a raw food
diet. As shown in this study the main determi-
nant for the BMI and the incidence of amen-
orrhea is the amount of raw food in the diet.
On the basis of the data obtained and the
reports in the literature, a strict raw food diet
with amounts of raw food over 90% cannot be
recommended. Studies yet to be published
with diets containing liberal amounts of raw
food indicate that about half the food eaten in
an uncooked form may be optimal for health
under normal conditions.
78
Ann Nutr Metab 1999;43:69–79
Koebnick/Strassner/Hoffmann/
Leitzmann
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