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Calcium Supplementation with Calcium-Rich Mineral Waters: A Systematic Review and Meta-analysis of its Bioavailability

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Abstract and Figures

The relevance of calcium (Ca2+), an essential bone mineral, to the prevention and treatment of osteoporosis is well established. However, a good deal of evidence casts doubt on the validity of current RDAs (recommended daily allowance), i.e., 800-1000 mg/day. New guidelines consistently advocate higher daily intakes (up to 1500 mg/day), a goal that may be difficult to achieve for many patients. Environmental as well as individual behavioral factors may limit the consumption of dairy products, whereas calcium supplements require a high level of compliance and cause additional costs. Calcium-rich mineral waters may offer a promising alternative. A systematic literature search was performed (Medline, years 1966-1998) to identify experimental studies on the bioavailability of calcium-rich mineral waters. First, all publications on calcium absorption from mineral waters were identified, and, in a second step, studies comparing calcium absorption from mineral waters with that from dairy products. Four studies fulfilled all inclusion criteria. A meta-analysis based on published p values indicated calcium absorption from mineral waters was significantly higher (p = 0.03) than that from dairy products. Although only few studies with a relatively small number of subjects are available to date, the bioavailability of calcium from calcium-rich mineral waters thus seems to be at least comparable to, and possibly better than, that from dairy products. These results are in keeping with the assumption that calcium-rich mineral water is a useful calcium source to achieve new, higher recommended daily allowances of calcium.
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Original Article
Calcium Supplementation with Calcium-Rich Mineral Waters: A
Systematic Review and Meta-analysis of its Bioavailability
H. BoÈhmer, H. Mu
ller and K.-L. Resch
Saxon Balneology and Rehabilitation Medicine Research Institute, Bad Elster, Germany
Abstract. The relevance of calcium (Ca
), an essential
bone mineral, to the prevention and treatment of
osteoporosis is well established. However, a good deal
of evidence casts doubt on the validity of current RDAs
(recommended daily allowance), i.e., 800±1000 mg/day.
New guidelines consistently advocate higher daily
intakes (up to 1500 mg/day), a goal that may be dif®cult
to achieve for many patients. Environmental as well as
individual behavioral factors may limit the consumption
of dairy products, whereas calcium supplements require
a high level of compliance and cause additional costs.
Calcium-rich mineral waters may offer a promising
alternative. A systematic literature search was performed
(Medline, years 1966±1998) to identify experimental
studies on the bioavailability of calcium-rich mineral
waters. First, all publications on calcium absorption from
mineral waters were identi®ed, and, in a second step,
studies comparing calcium absorption from mineral
waters with that from dairy products. Four studies
ful®lled all inclusion criteria. A meta-analysis based on
published p values indicated calcium absorption from
mineral waters was signi®cantly higher (p = 0.03) than
that from dairy products. Although only few studies with
a relatively small number of subjects are available to
date, the bioavailability of calcium from calcium-rich
mineral waters thus seems to be at least comparable to,
and possibly better than, that from dairy products. These
results are in keeping with the assumption that calcium-
rich mineral water is a useful calcium source to achieve
new, higher recommended daily allowances of calcium.
Keywords: Bioavailability; Calcium; Mineral water;
Osteoporosis; Recommended daily allowance
Calcium plays an important role in the human body as an
essential bone mineral [1] as well as a messenger in
signal transduction [2±6]. Its concentration is regulated
by a variety of hormones [7±11]. In principle, the
healthy body is able to eliminate excess calcium, but is
unable to cope with low calcium intake for a extended
period of time [1,12,13].
Current RDAs (recommended daily allowance) have
increasingly been put in question [14], and new
guidelines consistently advocate higher daily intakes
[15±18]. This goal may be dif®cult to achieve for many
patients [19±24]. Supplementation with dairy products is
commonly suggested [25,26], although environmental as
well as individual behavioral factors may limit the
consumption of dairy products. Pharmaceutical prepara-
tions require a high level of compliance and cause
additional costs.
Calcium-rich mineral water, popular beverages free of
calories, may offer an interesting alternative, provided
they have an adequate calcium bioavailability. There-
fore, a systematic analysis of the literature on
bioavailability of calcium from calcium-rich mineral
waters should be performed.
First a systematic review on the topic should be
performed and, in a second step, published data should
Osteoporos Int (2000) 11:938±943
ß 2000 International Osteoporosis Foundation and National Osteoporosis Foundation
Correspondence and offprint requests to: Karl-Ludwig Resch, Saxon
Balneology and Rehabilitation Medicine Research Institute, Linden-
strasse 5, D-08645 Bad Elster, Germany. Tel: +49 37437 5570. Fax:
+49 37437 55777. e-mail:
be summarized in a meta-analysis, if possible. We
anticipated only a small number of publications so
decided to tailor details of data processing only after data
selection, but whenever possible in accordance with
commonly accepted standards, such as those of the
Cochrane Collaboration [27].
Study Identi®cation
A systematic electronic literature research was per-
formed to identify experimental studies on the bioavail-
ability of calcium-rich mineral waters. Databases used
were Medline (version Silverplatter 98, years 1966±
1998) and Current Contents. References of identi®ed
publications were checked. The search strategy in
Medline is shown in Table 1.
Study Selection
To be included in the meta-analysis studies had to
compare calcium absorption from mineral water with
that from dairy products in healthy volunteers. Because
of an anticipated increased co-morbidity potentially
in¯uencing absorption rates in the elderly, participants
should not be older than 70 years. Any co-medication
in¯uencing calcium homeostasis had to be excluded.
Participants could be of either gender.
An estimation of effect size can only produce valid
®gures if the within-study comparison between mineral
water and dairy products was appropriate. Since calcium
load and absorption fraction are inversely correlated
[28], it is necessary to include data in the meta-analysis
only if calcium load sizes have been adjusted for, e.g.,
with the same calcium load from mineral water and dairy
The question of whether calcium sources were taken
with meal or by fasting volunteers seems to be of similar
importance, because absorption of calcium increases
when it is taken with a meal [29]. Therefore, evidence
was required that both groups in a study were
comparable in that respect, enabling us to calculate
valid effect sizes from p values.
Data Synthesis
The data in publications comparing calcium absorption
fractions from mineral water with that from dairy
products were quantitatively summarized in a meta-
analysis and respective bioavailabilities were compared.
The comparison of calcium absorption fractions from
dairy products with those from mineral waters was based
on a meta-analysis of published or calculated p values
[30], since the necessary information to compute d
values for each study (e.g., mean values and standard
deviations) or t values were not consistently available.
The meta-analysis included the p value for the one-sided
hypothesis that dairy products show an equal or better
calcium absorption than mineral waters. For meta-
analyses it is necessary to use one-sided hypotheses
and p values [30].
A p value was explicitly published in only one study;
all other p values had to be estimated applying different
procedures. The p value of the study by Halpern et al.
[31] was estimated using the binomial test of the given
frequencies. For the studies by Couzy et al. [32] and van
Dokkum et al. [33] the p values were calculated using
the published means and standard deviations and
applying the more conservative Student's t-test for
independent samples (although these data were indeed
dependent in nature). There was no methodologic
alternative to this procedure, which produces a relatively
conservative p value. Thus underestimation of the
resulting p value is quite likely. In consequence, this
estimate is in favor of the assumption that the calcium
absorption fraction is higher for dairy products than for
mineral waters. The meta-analysis of p values gives a
correlation coef®cient r as effect size parameter, which
was transformed to a more convenient d value by a
formula suggested by Rosenthal [34].
Subgroup analysis seemed inappropriate due to the
small number of studies available.
We identi®ed six publications [31±37] with experimental
data on calcium absorption from mineral waters (Table
2). All six publications were identi®ed through the
Medline search. Neither the search in Current Contents
nor the check of references produced additional results.
All ®ve studies with published absorption fractions
used the tracer technique, with either stable [32,33] or
unstable isotopes [31,35,37]. From different measure-
Table 1. Medline search strategy to identify publications on calcium
absorption from mineral water
#1 ``MINERAL-WATERS''/ all subheadings
#2 explode ``BALNEOLOGY''/ all subheadings
#3 ``HEALTH-RESORTS''/ all subheadings
#8 ``CALCIUM''/ all subheadings
#12 #8 or #9
#13 #12 not #11
#14 #1 or #2 or #3 or #4 or #7 or #10
#15 #14 and #13
*Indicates truncation of the search term allowing for anything as
second part of the word
Calcium Supplementation with Calcium-Rich Mineral Waters 939
ment technologies this isotopic tracer technique cur-
rently provides the most precise method for determining
calcium absorption from different sources [38±40].
Four studies compared absorption fractions from dairy
products and mineral waters. These studies were
included in the meta-analysis [31±35], as they ful®lled
all inclusion criteria.
The other two studies were not included. Guillemant
et al. [36] used a different type of outcome parameter,
i.e., measurement of the parathyroid hormone concen-
tration. Wynkel et al. [37] compared absorption fractions
of different mineral waters, but did not compare them
with those of dairy products.
Table 2. Publications on calcium absorption from mineral waters
Publication Year n Subjects Results AR
Halpern et al. [31] 1991 15 Lactose-intolerant adults Calcium bioavailability from mineral water at
least comparable to dairy products. Mineral
water is a useful calcium source for lactose-
intolerant adults
No Yes
Heaney and Dowell [35] 1994 18 Healthy women Calcium bioavailability from mineral water at
least comparable to dairy products
Yes Yes
Couzy et al. [32] 1995 9 Healthy women Calcium bioavailability from mineral water
comparable to dairy products
Yes Yes
Van Dokkum et al. [33] 1996 12 Healthy young adult women Calcium bioavailability from mineral water
(37.0%) comparable with dairy products
(37.7±42.2%). Combined with a spaghetti
meal, calcium bioavailability from mineral
water increases signi®cantly (46.1%)
Yes Yes
Guillemant et al. [36] 1997 12 Healthy young adult men Inhibition of PTH-secretion induced by mineral
No No
Wynckel et al. [37] 1997 12 Students (8 men, 4 women) The intestinal calcium absorption from mineral
waters with three different concentrations
(10.4, 78 and 467 mg/l) is comparable.
Calcium-rich mineral water is a useful calcium
source for the elderly and patients with lactose
Yes No
.Absorption fractions published.
.Comparison of dairy (D) and mineral water (M).
Table 3. Calcium absorption from mineral water and calcium load
Study n Mean
Heany and Dowell [35] 18 47.5 100 No data
Couzy et al. [32] 9 23.8 248 4.8
van Dockum et al. [33] 12 37.0 150 9.8
Wynckel et al. I
[37] 12 34.1 200 15.4
Wynckel et al. II
[37] 12 37.0 200 8.3
Wynckel et al. III
[37] 12 36.1 200 13.0
.Calcium absorption fractions of three different mineral waters ( I, II
and III).
Fig. 1. Mean absorption fraction versus calcium load.
Table 4. Four studies comparing calcium absorption from mineral
water and dairy products
Study np
Halpern et al. [31] 15 0.0547 Minieral water vs milk; 8
subjects with a higher
calcium absorption from
mineral water, 2 subjects
with a higher absorption
from milk, p value
calculated from binomial
Heany and Dowell [35] 18 0.0175 Mineral water vs milk
Couzy et al. [32] 9 0.668 Mineral water vs milk; p
value conservatively
estimated from Student's t-
test for independent
van Dokkum et al. [33] 12 0.568 Mineral water vs cheese; p
value conservatively
estimated from Student's t-
test for independent
.p value for the one-sided hypothesis that calcium bioavailability
from dairy products to equal to or higher than that from mineral water.
940 H. BoÈhmer et al.
The mean absorption fractions of all included studies
are shown in Table 3. Figure 1 plots the mean absorption
fractions versus calcium load, and shows the known
inverse correlation between the two [27], with a range
from 23.8% (248 mg calcium load) to 47.5% (100 mg
calcium load).
Studies including a comparison of calcium absorption
from mineral waters with that from milk or dairy
products are shown in Table 4. The meta-analysis of p
values indicated a signi®cantly higher calcium absorp-
tion from mineral waters than from dairy products
(p = 0.03). The observed effect size was r = 0.27,
corresponding to a d value of 0.56, which indicates a
moderate effect size. The 95% con®dence interval of the
d value was 70.02 to 1.19 and a chi-square test of
homogeneity among studies revealed no signi®cant
differences (w
= 4.8, d.f. = 3, p = 0.19).
An adequate calcium alimentation of the population is an
increasingly important target. Because of demographic
changes due to increasing life expectancy, osteoporosis
is about to become a major problem for Western health
care systems [41] with enormous economic conse-
quences [42]. Main preventive strategies aim at raising
peak bone mass [43] and at a reduction of age-related
bone loss [44] in order to delay for as long as possible a
drop in bone mineral content below the fracture
The relevance of adequate calcium intake seems to be
well established. Recommended daily intakes are
dependent on age and sex [45]. According to studies
from the last decade children and adolescents, perime-
nopausal women and the elderly have a particular high
demand for calcium, of up to 1000±1500 mg per day
[15±18,46,47]. It was demonstrated that these groups do
not reliably achieve desirable intakes through their
normal diet: dietary calcium intake assessed with food-
frequency questionnaires normally reaches 600±800 mg
calcium per day [19,21±24], rarely higher [48].
It seems necessary, therefore, to facilitate daily
calcium intake as much as possible. This means that
preference should be given to adequate dietary intake
over substitution of calcium salts. A choice of different
options of intake might positively affect compliance and
effectiveness. In this respect calcium-rich mineral waters
may offer an alternative to the `standard' recommenda-
tion of milk and dairy products, or complement this
suggestion. Between 1 and 2 l of a typical calcium-rich
mineral water with a concentration of about 500 mg
calcium/l can help satisfy even an increased demand
(Table 5). This recommendation is based on the
assumption of an adequate bioavailability of the ingested
calcium. The bioavailability depends on the absorption
fraction, i.e., the proportion of absorbed calcium and
dietary calcium intake.
The mean absorption fractions from the ®ve studies
where absorption fractions were available, are similar to
that of dairy products in other studies. Heaney et al.
reported a calcium absorption fraction for milk of 31.7%
[49] in one study and 26.7% in a second [50]. Studies
analyzing calcium absorption from pharmaceutical
preparations report rates of about 25±35% [51±56].
Although only a few studies with a relatively small
number of subjects are available, the bioavailability of
calcium from calcium-rich mineral waters seems to be at
least comparable to, and possibly better than, that from
dairy products or pharmaceutical preparations.
Mineral waters are not monosubstances. Often
different minerals are leached in relevant concentrations.
Available study results indicate that calcium absorption
is not substantially in¯uenced by other accompanying
ion species, e.g., Wynkel et al. [37] observed no
signi®cant difference in absorption fractions of different
calcium-rich mineral waters (Table 6).
It should be mentioned, however, that accompanying
ion species could in¯uence urinary calcium excretion. In
particular, sodium may increase urinary calcium [57±
60]. Clinical studies indicate a correlation between levels
of urinary sodium and calcium. This correlation is in the
®rst place sodium-driven, i.e., the sodium load in¯uences
the urinary calcium level. One hundred millimoles
sodium may take out approximately 1 mmol of calcium
Table 5. Some mineral waters with their calcium contents
Brand name Calcium (mg/l) Country
Contrex 486 France
Adelborner 569 Switzerland
Eptinger 555 Switzerland
St. Augustinus 585 Germany
Schillerquelle Ensingen 585 Germany
St Margareten 566 Germany
Ferrarelle 368 Italy
Table 6. Ion concentration of tested mineral waters (mg/l)
Study Brand name Na
Sulphates HCO
Heany and Dowell [35] Sangemini 16.50 3.20 318.00 14.60 15.00 42.00 1000.00 23.30
Van Dokkum et al. [33] Ferrarelle 47.00 45.00 368.00 17.00 22.00 5.00 1385.00
Halpern et al. [31] Vittel Grande 3.80 2.00 202.00 36.00 7.20 306.00 402.00 6.00
Couzy et al. [32] Contrex 10.00 3.00 466.00 83.00 8.00 1160.00 403.00
Wynckel et al. [37] Mineral water I 8.0 5.4 10.4 6.0 7.5 6.7 64.0 4.0 30.5
Mineral water II 5.0 1.0 78.0 24.0 4.5 10.0 387.0 3.8 13.5
Mineral water III 7.0 3.0 467.0 84.0 7.0 1192.0 377.0 3.2 8.0
Calcium Supplementation with Calcium-Rich Mineral Waters 941
[61,62], according to a report on higher calcium loss
[63]. Consumers should therefore consider the level of
sodium when choosing a mineral water, not because of
its bioavailability but because of its biological activity.
Guillemant et al. [36] showed that the body reacts to
calcium supplemented from mineral water. The observed
reduction in the parathyroid hormone level could be
considered an indicator of the biological activity of the
ingested calcium.
Epidemiologic data support the assumption that
chronic low dietary calcium intake promotes osteoporo-
sis [64,65]. An inverse correlation between calcium
intake and osteoporotic fracture rates has been demon-
strated in several studies [66±69]. Osteoporotic bone loss
was reduced by 25% through adequate calcium
supplementation, especially in high-risk groups such as
women over 65 years of age [44]. Even a signi®cant
reduction in the rate of dangerous hip fractures due to
calcium supplementation has been demonstrated in a
clinical trial [68]. Clinical evidence of such biological
effects was shown by Cepollaro et al. [70] for calcium-
rich mineral waters. In a controlled clinical trial they
observed a signi®cant reduction in postmenopausal bone
loss with calcium supplementation.
Although data are available from only a few studies with
a relatively small number of subjects, calcium-rich
mineral waters seem to offer an interesting, effective
alternative to calcium supplementation from milk and
dairy products because of their comparable or possibly
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Received for publication 24 August 1999
Accepted in revised form 29 March 2000
Calcium Supplementation with Calcium-Rich Mineral Waters 943
... 59 Mahmood [37] Mandovi River, Goa, India 0-35. 65 Jagtap et al. [38] Moheshkhali Coast, Cox's Bazar 18-33 (pore water) Present study ...
... Calcium-rich water is favorable to bone formation [64]. Bohmer et al. [65] reported that "High calcium in waters seem to offer an interesting, effective substitute to calcium supplementation from milk and dairy products because of their similar or possibly even better bioavailability of calcium." A suitable amount of calcium intake is important for achieving peak bone mass and inhibition of osteoporosis [66][67][68][69], while insufficient calcium intake is a risk for osteoporosis in humans that affect bone [70,71]. ...
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The present study was conducted on salt marsh bed (Spartina alterniflora) at Moheshkhali coastal area, Cox's Bazar, Bangladesh. Some physicochemical factors, namely temperature, salinity, pH, DO, NO3-N, PO4-P, Ca (%), fat (%), moisture (%) and ash (%) were analyzed. In the present study, pore water temperature varied between 24°C and 28°C. The highest value of the temperature of pore water of S. alterniflora bed was recorded as 28° ± 1.26°C in July from station 3. Salinity was found between 18‰ and 33‰ in the present study. The value of pH, DO, NO3-N, PO4-P, Ca, protein, fat, moisture and ash ranged for 6.4-7.6; 0.95-2.04 mg/L; 1.38-1.72 µg/g; 1.83-2.47 µg/g; 101-119 mg/kg; 11.1%-12.35%; 0.32%-0.51%; 17.96%-21.1% and 19.58%-21.3% at S. alterniflora bed, respectively. Temperature, salinity, pH, and NO2-N showed significant variations in different month (P < 0.05). Substantial changes were found in the concentrations of DO, Ca, protein, fat, and moisture in terms of sites (P < 0.05). Very strong linear relationships were found in Ca (%) vs. PO4-P (r = 0.953); fat (%) vs. protein (%) (r = 0.942); PO4-P vs. NO3-N (r = 0.932); pH vs. temperature (r = 0.928); Ca (%) vs. NO3-N (r = 0.917); and fat (%) vs. Ca (%) (r = 0.891) at the significance level 0.01. Strong relationships were observed in fat (%) vs. PO4-P (r = 0.784), moisture (%) vs. DO (r = 0.782), fat (%) vs. NO3-N (r = 0.752), PO4-P vs. protein (%) (r = 0.710) and temperature vs. moisture (%) (r = 0.603) at the alpha level 0.01. The present study suggest that the variation of parameters were strongly correlated with nutrients and the hydrological parameters as well as minerals of the salt marsh (S. alterniflora) plant.
... First, the paper evaluates only food-based supplies of nutrients and does not consider fortification or supplementation as strategies to obtain nutrients. Indeed, several studies have been conducted on supplementing calcium, as an example, and results on how milk compares with supplemental calcium sources in terms of bioavailability have been inconsistent (Recker et al., 1988;Böhmer et al., 2000;Zhao et al., 2005). Such supplements or calcium-fortified foods may be especially significant for populations with higher frequencies of conditions, including lactose intolerance and milk allergy, that prevent them from consuming milk. ...
... Future work should more holistically consider the benefit of supplementing critical nutrients such as calcium, rather than attempting to obtain daily calcium requirements exclusively from food in the context of feeding the growing global population. Several efforts have also focused on fortification of calcium in food products such as mineral waters (Böhmer et al., 2000), suggesting that these products also have bioavailability similar to that of milk. A need exists to build on these initial assessments of supplementation and fortification to consider trade-offs associated with these processes as a strategy for feeding humans in the global context. ...
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Globally, ruminant production systems used to synthesize meat and milk differ tremendously in terms of their efficiency, productivity, and environmental impacts. Regardless of this variability, milk has been repeatedly identified as an essential source of nutrients for humans. The objective of this work was to characterize global contributions of fluid milk to human food and nutrient supplies, greenhouse gas emissions, and water withdrawal. Data were leveraged from the United Nations Food and Agriculture Organization to estimate global supplies of agricultural products. Trade of agricultural products and waste of those products, along with use of human food for livestock feed were accounted for before estimating human nutrient supplies. The contributions of milk to human-edible nutrient supplies were then enumerated in terms of their proportion of total nutrients supplied by the agricultural system and in terms of the human population's requirement for that nutrient. We identified that fluid milk provides over 10% of consumable supplies of vitamin B12, vitamin A, riboflavin, and calcium available for humans globally. In terms of human nutrient requirements, milk provides sufficient vitamin B12 to meet the needs of over 60% of the global population, riboflavin to satisfy 50% of the population, and calcium and phosphorus for over 35% of the population. Compared with other foods, milk ranked among the highest in terms of nutrient-to-calorie ratio for numerous amino acids, phosphorus, calcium, and riboflavin. Conditional dependencies were identified between greenhouse gas emissions and ruminant milk and meat, but not between water withdrawal and milk production. When evaluating the trade-offs in nutrient use versus nutrient provision for producing milk or producing all ruminant products, the production of ruminants worldwide was associated with both net increases and net decreases of several key nutrients. Continued work focusing on strategies to reduce the environmental impact of milk production will improve the utility of milk for feeding the growing global population.
... Según (Böhmer et al., 2000), refieren que la dureza del agua es un constituyente inespecífico debido principalmente al calcio y el magnesio ya que ni la legislación española ni la OMS establecen un límite máximo basándose en la falta de evidencia de asociación entre dureza del agua y salud. Cuando se revisan las recomendaciones sobre el tipo de agua de consumo público en la infancia, se acostumbra a restarle importancia al calcio. ...
... Por lo que podemos afirmar que respecto a dicho autor la ingesta recomendada diaria hallado en los reservorios trabajados los porcentajes de aporte estaría cubriendo el 50% de lo encontrado por este autor. Así también (Böhmer, 2000) dicen que el calcio del agua tiene una biodisponibilidad semejante a la de la leche y además contribuye a la resorción ósea si se toma a lo largo del día. Por ello (Ross et al., 2010) refieren que asumiendo una ingesta de agua recomendada diaria y si el agua contiene entre 50-100 mg/L de calcio, ésta aportaría entre 5.8-17.6% ...
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Las aguas naturales constituyen un alimento saludable que aporta nutrientes esenciales como el calcio y el magnesio, que tiene relevancia en casos de consumo insuficiente de productos lácteos y derivados, pues el calcio del agua mineral es recomendable por su fácil biodisponibilidad. Este trabajo tiene como objetivo determinar el contenido de calcio y magnesio en los reservorios de agua de Abancay y su aporte en la ingesta recomendada diaria, para ello se recolectaron muestras de los 6 reservorios de agua, dicha colección se hizo en botellas de vidrio para luego ser enviadas al laboratorio de Evaluación Nutricional de Alimentos de la Facultad de Ciencias Agrarias de la UNA Puno para ser analizadas por el método de espectrofotometría de absorción atómica. Los resultados fueron: el aporte a la ingesta recomendada diaria para niños de 4 a 8 años respecto al calcio varía entre 5,93% a 10,64% y rmagnesio de 24,02 a 56,33%; para adolescentes de 7,74 a 10,07% en cuanto al calcio y 11,58 a 36,11% de magnesio y para adultos el aporte fue de 7,29 a 13,09% de calcio y 7,72 a 24,07% de magnesio; llegando a la conclusión que el porcentaje de aporte a la ingesta recomendada de calcio y magnesio del agua de consumo público cubre una parte importante en la ingesta recomendada diaria para los 3 grupos etáreos siendo el agua potable una fuente importante de calcio y magnesio especialmente para aquellas personas que tienen baja ingesta de estos minerales.
... It is important to note that the findings from these studies should be interpreted cautiously due to factors such as limited sample sizes, different methodologies, and variability in the mineral compositions of the waters studied. The mechanisms by which calcium-rich mineral water might influence cardiovascular health are multifaceted and interconnected, involving direct and indirect effects [81,82]. Blood Pressure Regulation: Some studies have suggested that calcium can play a role in regulating blood pressure. ...
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This systematic review investigates the potential health and wellness benefits of natural calcium-rich mineral waters. It emphasizes the importance of dietary calcium sourced from natural mineral waters in promoting bone health, maintaining cardiovascular function, aiding in weight management, and enhancing overall well-being. The review process involved the comprehensive analysis of peer-reviewed articles, clinical trials, and experimental studies published within the last decade. Findings reveal that consuming calcium-rich mineral water can contribute significantly to daily calcium intake, particularly for those with lactose intolerance or individuals adhering to plant-based diets. The unique bioavailability of calcium from such waters also appears to enhance absorption, thus potentially offering an advantage over other calcium sources. The potential benefits extend to the cardiovascular system, with some studies indicating a reduction in blood pressure and the prevalence of cardiovascular diseases. Emerging evidence suggests that calcium-rich mineral water might have a role in body weight management, though further research is needed. The review identifies several areas requiring additional research, such as the potential interaction between calcium-rich mineral water and other dietary components, the effects on populations with specific health conditions, and the long-term effects of consumption. In conclusion, natural calcium-rich mineral waters show promise as a readily accessible and bioavailable sources of dietary calcium, potentially beneficial for a broad range of individuals. However, further investigation is required to fully understand its range of health impacts and define optimal intake levels.
... 21 Assuming it can be made safe and accessible and that sensory acceptability findings from this small sample in Argentina would apply in other countries, drinking water could potentially be a good alternative vehicle to improve calcium in the diet. [24][25][26][27] This study, based on simulated diets using dietary data from the overall population, explored the potential of calcium-fortified wheat flour and water to complement the FBRs of local food sources of calcium in reaching the daily recommended Ca PRIs of four population groups (12-to 23-month-old and 4-to 6-year-old young children, adolescent girls, and NPNB women) across Bangladesh, Guatemala, and Uganda, where previous analysis showed that it was difficult or not possible to meet calcium intake targets using diets based on local foods alone. Specifically, the objectives were: ...
Adequate calcium intake is essential for health, especially for infants, children, adolescents, and women, yet is difficult to achieve with local foods in many low- and middle-income countries. Previous analysis found it was not always possible to identify food-based recommendations (FBRs) that reached the calcium population recommended intake (PRI) for these groups in Bangladesh, Guatemala, and Uganda. We have modeled the potential contribution of calcium-fortified drinking water or wheat flour to FBR sets, to fill the remaining intake gaps. Optimized diets containing fortified products, with calcium-rich local foods, achieved the calcium PRI for all target groups. Combining fortified water or flour with FBRs met dietary intake targets for adolescent girls in all geographies and allowed a reduction from 3-4 to the more feasible 1-2 FBRs. Water with a calcium concentration of 100 mg/L with FBRs was sufficient to meet calcium targets in Uganda, but higher concentrations (400-500 mg/L) were mostly required in Guatemala and Bangladesh. Combining calcium-fortified wheat flour at 400 mg/100 g of flour and the FBR for small fish resulted in diets meeting the calcium PRI in Bangladesh. Calcium-fortified water or flour could improve calcium intake for vulnerable populations, especially when combined with FBRs based on locally available foods.
... Meat contains bivalent iron that is absorbed more efficiently than the trivalent form found in plant sources such as legumes, whole grains, or tofu, while cow's milk is a good source of calcium. However, it seems negligent and divorced from the reality of many people's lives not to inform them that they can also meet their iron needs with plant-based foods in combination with vitamin C (which promotes intake efficiency), or their calcium needs with calcium-rich mineral water, green leafy vegetables, or calcium-fortified plant milk (51,52). Note that the calcium bioavailability of certain green leafy vegetables like kale, broccoli, and turnip greens is even higher (>50%) than cow's milk and dairy products (∼30%) (51). ...
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Discussing plant-based diets and substitutions for animal-based foods in food-based dietary guidelines (FBDGs) can be a key step in making dietary recommendations more sustainable and healthy, as well as more inclusive. The existing large-scale evaluations of FBDGs do not assess whether and to what extent different countries cover the broad spectrum of plant-based diets and have policy positions on vegetarian diets (including vegan diets), and whether they mention specific plant-based alternatives to milk, dairy products, and meat. The main aim of this state-of-the-art review was to determine whether and how FBDGs provide such information. 95 guidelines and 100 corresponding countries were assessed, using an exploratory sequential mixed method. This involves a qualitative explorative content analysis of the guidelines, followed by a hierarchical cluster analysis. Furthermore, the Balanced Food Choice Index (BFCI) was constructed, which measures the extent to which FBDGs provide recommendations that cover the broad spectrum of plant-based diets (with some or no animal-based products). In order to explore the correlations between FBDGs’ recommendations and ecological and economic country characteristics, ordinary least squares regression was used. It was found that most countries do not provide information to their citizens that cover the broad spectrum of plant-based diets, indicated by the mean score of the BFCI (33.58 out of 100 points). A total of 38 guidelines (40%) contain a position on vegetarian diets. Nearly half (45%) of all FBDGs already mention plant-based alternatives to meat or animal milk. The regressions showed that the BFCI correlates positively with countries’ ecological efforts and negatively with the importance of animal-based products in their economy. This study demonstrates a considerable information insufficiency in current FBDGs worldwide. FBDGs should provide recommendations for the broad spectrum of plant-based diets and balance the ethical, ecological, religious, and economic aspects that play a role in people's food choice.
Zusammenfassung Mineral- und Heilwässer zeichnen sich durch eine sortenspezifische Zusammensetzung aus, so dass sich die Wässer auch ausernährungsphysiologischer Sicht voneinander unterscheiden. Viele Mineral- und Heilwässer bilden eine quantitativ bedeutsame Quelle für gut bioverfügbares Calcium und Magnesium. Calciumreiche Wässer stellen somit eine günstige Alternative zum gut löslichen Calciumcitrat dar, wie es in der Leitlinie der Bone Health & Osteoporosis Foundation bei Achlorhydrie oder eingeschränkter Magensäureproduktion (z. B. Therapie mit Protonenpumpeninhibitoren) als Calciumquelle empfohlen wird. Calciumwässer senken den Serumspiegel an Parathormon ähnlich stark wie Calcium aus Milch oder Supplementen mit einem äquivalenten Gehalt des Mineralstoffs. Damit verbunden ist bei alkalischen Calciumwässern eine Hemmung der Knochenresorption. Auch senken bikarbonatreiche Wässer die renale Säurelast sowie die Calciumverluste über den Urin. Ungeklärt ist der Einfluss der Wässer auf die Calciumbilanz und das Frakturrisiko. Der Natrium- und Kaliumgehalt der meisten Wässer ist zu gering, um den Knochenstoffwechsel nennenswert beeinflussen zu können. Auch üben Wässer mit moderatem Fluoridgehalt (0,70-1,0 mg/l) keinen, von anderen Nahrungsfaktoren (Calcium, Protein) unabhängigen Einfluss auf die Mikrostruktur der Knochen aus.
Early dietary treatment is mind-saving in patients with phenylketonuria. A "diet-for-life" is advocated, aimed to prevent effects of chronic exposure to hyperphenylalaninemia. While adherence to diet is significant during childhood as patients are followed-up at specialized metabolic centers, during adolescence and adulthood percentage of patients discontinuing diet and/or lost at follow-up is still high. The process of passing skills and responsibilities from pediatric team to adult team is defined "transition". The goal of transition clinics is to set up specific multidisciplinary care pathways and guarantee continuity of care and compliance of patients to care. In 2017, "The complete European guidelines on phenylketonuria" were published. These guidelines, however, do not provide an easy way to illustrate to adult patients how to follow correct dietary approach. The purpose of this review is to evaluate current evidence on optimum dietary treatment of adults with phenylketonuria and to provide food pyramid for this population. The pyramid built shows that carbohydrates should be consumed every day (3 portions), together with fruits and vegetables (5 portions), extra virgin olive oil, and calcium water (almost 1 L/day); weekly portions can include 150 g potatoes walnuts and hazelnuts (20 g). At top of pyramid, there are two pennants. The green means that, based on individual metabolic phenotype and daily phenylalanine tolerance, patients need personalized supplementation (specific phenylalanine free amino acid mixtures, vitamins and omega 3 fatty acids); the one red indicates foods that are banned from diet (aspartame and protein foods exceeding individual dietary phenylalanine tolerance).
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Bone fragility is the susceptibility to fracture due to poor bone strength. This condition is usually associated with aging, comorbidities, disability, poor quality of life, and increased mortality. International guidelines for the management of patients with bone fragility include a nutritional approach, mainly aiming at optimal protein, calcium, and vitamin D intakes. Several biomechanical features of the skeleton, such as bone mineral density (BMD), trabecular and cortical microarchitecture, seem to be positively influenced by micro- and macronutrient intake. Patients with major fragility fractures are usually poor consumers of dairy products, fruit, and vegetables as well as of nutrients modulating gut microbiota. The COVID-19 pandemic has further aggravated the health status of patients with skeletal fragility, also in terms of unhealthy dietary patterns that might adversely affect bone health. In this narrative review, we discuss the role of macro- and micronutrients in patients with bone fragility during the COVID-19 pandemic.
Het aantal personen dat kiest voor een op planten gebaseerde voeding neemt toe omwille van onder meer bezorgdheid over het milieu en het klimaat. Wat volgt is gebaseerd op twee recente consensusrichtlijnen over vegetarische voeding van de Vlaamse Vereniging voor Kindergeneeskunde en de Hoge Gezondheidsraad. Een vegetarisch voedingspatroon hangt samen met lagere cardiovasculaire morbiditeit en mortaliteit, en een lagere prevalentie van obesitas. De groei van vegetarisch gevoede kinderen is gelijkaardig aan die van omnivore leeftijdgenoten, op voorwaarde dat de energieaanbreng voldoende is. Bij adolescenten hangt vegetarisme soms samen met eetstoornissen, maar er is géén evidentie voor een causaal verband. Een evenwichtig gevarieerd lacto-ovo-vegetarisch voedingspatroon kan voldoen aan alle behoeften, ook van een groeiend kind. Een veganistische voeding, die alle voedingsmiddelen van dierlijke oorsprong uitsluit, moet in elk geval aangevuld worden met een vitamine B12-supplement of vitamine B12-gesupplementeerde voedingswaren. Ook belangrijk is aandacht voor de inname van calcium en van voedingsmiddelen die voldoende energie en eiwit van goede kwaliteit bevatten. Hoe restrictiever het voedingspatroon, en hoe jonger het kind, des te groter het risico op deficiënties, tenzij gebruikgemaakt wordt van supplementen of gesupplementeerde producten.
To assess the effect of dietary calcium intake on risk of hip fracture, a geographically defined caucasian population in southern California was studied prospectively. Between 1973 and 1975, a quantified 24 hour diet recall was obtained by a dietician from 957 men and women aged 50 to 79 years at baseline. Follow-up to 1987 with mortality records and interviews showed 15 men and 18 women with hip fractures. The age-adjusted risk of hip fracture was inversely associated with dietary calcium whether considered as mg per day or as nutrient density (mg per 1000 kcal). No other nutrient was consistently associated with hip fracture in any Cox proportional hazards model that included calcium. The association between calcium and fracture persisted after adjustment for cigarette smoking, alcohol intake, exercise, and obesity. The significant independent inverse association of dietary calcium with subsequent risk of hip fracture (relative risk = 0.6 per 198 mg/1000 kcal) strongly supports the hypothesis that increased dietary calcium intake protects against hip fracture.
The National Institutes of Health Consensus Development Conference on Optimal Calcium Intake brought together experts from many different fields including osteoporosis and bone and dental health, nursing, dietetics, epidemiology, endocrinology, gastroenterology, nephrology, rheumatology, oncology, hypertension, nutrition and public education, and biostatistics, as well as the public, to address the following questions: 1) What is the optimal amount of calcium intake? 2) What are the important cofactors for achieving optimal calcium intake? 3) What are the risks associated with increased levels of calcium intake? 4) What are the best ways to attain optimal calcium intake? 5) What public health strategies are available and needed to implement optimal calcium intake recommendations? and 6) What are the recommendations for future research on calcium intake? The consensus panel concluded that: A large percentage of Americans fail to meet currently recommended guidelines for optimal calcium intake. On the basis of the most current information available, optimal calcium intake is estimated to be 400 mg/day (birth-6 months) to 600 mg/day (6-12 months) in infants; 800 mg/day in young children (1-5 years) and 800-1,200 mg/day for older children (6-10 years); 1,200-1,500 mg/day for adolescents and young adults (11-24 years); 1,000 mg/day for women between 25 and 50 years; 1,200-1,500 mg/day for pregnant or lactating women; and 1,000 mg/day for postmenopausal women on estrogen replacement therapy and 1,500 mg/day for postmenopausal women not on estrogen therapy. Recommended daily intake for men is 1,000 mg/day (25-65 years). For all women and men over 65, daily intake is recommended to be 1,500 mg/day, although further research is needed for this age group. These guidelines are based on calcium from the diet plus any calcium taken in supplemental form. Adequate vitamin D is essential for optimal calcium absorption. Dietary constituents, hormones, drugs, age, and genetic factors influence the amount of calcium required for optimal skeletal health. Calcium intake, up to a total intake of 2,000 mg/day, appears to be safe in most individuals. The preferred source of calcium is through calcium-rich foods such as dairy products. Calcium-fortified foods and calcium supplements are other means by which optimal calcium intake can be reached in those who cannot meet this need by ingesting conventional foods. A unified public health strategy is needed to ensure optimal calcium intake in the American population. The full text of the consensus panel's statement follows.
Calcitonin (CT) is a 32 amino acid peptide hormone, and its existence was postulated in 1962 by Copp and colleagues (Copp et al, 1962) (for review see Queener & Bell, 1975; Maclntyre et al, 1988; Wimalawansa & Maclntyre, 1989b). Initial studies on sheep suggested the parathyroid gland as the source of CT (Copp & Henze, 1964). Later, the source of this calcium lowering factor was identified as the thyroid gland (Foster et al, 1964a). CT is synthesised by the parafollicular cells (C-cells) of the thyroid in mammals (Foster et al, 1964b; Pearse, 1966; Bussolati and Pearse, 1967); and by C-cells associated with the ultimobranchial gland in lower vertebrates (Copp et al, 1967; Tauber, 1967). The C-cells derive from the neural crest (Le Dourain and Le Leivre, 1970) and migrate forward to become the ultimobranchial body in lower vertebrates and the parafollicular cells in man (Pearse & Polak, 1971) and related species (Pearse and Carvalheira, 1967).
Objective: To recommend appropriate levels of calcium intake in light of the most recent studies. Options: Dietary calcium intake, calcium supplementation, calcium and vitamin D supplementation; ovarian hormone therapy in postmenopausal women. Outcomes: Fracture and loss of bone mineral density in osteoporosis; increased bone mass, prevention of fractures and improved quality of life associated with osteoporosis prevention. Evidence: Relevant clinical studies and reports were examined, in particular those published since the 1988 Osteoporosis Society of Canada position paper on calcium nutrition. Only studies in humans were considered, including controlled, randomized trials and prospective studies, using bone mass and fractures as end-points. Studies in early and later phases of skeletal growth were noted. The analysis was designed to eliminate menopause as a confounding variable. Values: Preventing osteoporosis and maximizing quality of life were given a high value. Benefits, harms and costs: Adequate calcium nutrition increases bone mineral density during skeletal growth and prevents bone loss and osteoporotic fractures in the elderly. Risks associated with high dietary calcium intake are low, and a recent study extends this conclusion to the risk of kidney stones. Lactase-deficient patients may substitute yogurt and lactase-treated milk for cow's milk. True milk allergy is probably rare; its promotion of diabetes mellitus in susceptible people is being studied. Recommendations: Current recommended intakes of calcium are too low. Revised intake guidelines designed to reduce bone loss and protect against osteoporotic fractures are suggested. Canadians should attempt to meet their calcium requirements principally through food sources. Pharmaceutical calcium supplements and a dietician's advice should be considered where dietary preferences or lactase deficiency restrict consumption of dairy foods. Further research is necessary before recommending the general use of calcium supplements by adolescents. Calcium supplementation cannot substitute for hormone therapy in the prevention of postmenopausal bone loss and fractures. Adequate amounts of vitamin D are necessary for optimal calcium absorption and bone health. Elderly people and those who use heavy sun screens should have a dietary intake of 400 to 800 IU of vitamin D per day.
Many cells respond to external signals by generating pulses of the calcium ion in their cytoplasm, which somehow tells other cellular components to turn on or off. In his commentary, Putney poses this decoding problem and explains how a [report][1] by De Koninck and Schulman in this issue shows that one of calcium's main targets, the enzyme calcium-calmodulin, has intrinsic properties that allow it to translate the pulses into useful information for the cell. [1]:
The effect of different types of calcium supple- ments on total nutrient intake has not been studied. The effect of dietary calcium supplementation (calcium tablets or skim milk powder) on nutrient intake in 64 postmenopausal women was studied in a 4-y longitudinal study consisting of 2 y of intervention and 2 y of follow-up. Subjects also received advice on how to reduce their consumption of high-fat and cholesterol-rich foods. Analysis of 4-d weighed diet records at I y showed that calcium intakes from the milk-powder supplement (1618 ± 213 mg) and calcium tablets (1718 ± 257 mg) were above recommended di- etary intakes (RDI), and dietary fat intake and plasma cholesterol were significantly reduced compared with baseline values. The subjects supplemented with milk powder had higher intakes of several nutrients, including protein and zinc, compared with the subjects given calcium tablets. A greater proportion of subjects using the milk-powder supplement achieved � 70% of the RDI for zinc compared with tablet-supplemented subjects during the inter- vention study. Subjects were advised to continue with supplemen- tation at the end of the intervention study. Thirty-nine subjects were available for follow-up. The mean ( ± SD) calcium intake for the milk-powder group (942 ± 434 mg) was below the RDI and significantly lower than that of the calcium-tablet group (1346 ± 512 mg). These data suggest that advice on dietary calcium sup- plementation and fat reduction had a beneficial effect on the nutrient intakes of postmenopausal women but compliance outside of a control trial by women taking calcium tablets was higher than that by women taking milk powder. Thus, strategies to encourage women to increase calcium intake can be introduced without significant deleterious effects on other aspects of the diet. Am J Clin Nutr 1996:64:731-7.
True calcium absorption was studied as a function of the size of the ingested load in healthy adult women, under meal conditions and at loads ranging from 15 to 500 mg calcium. Fractional absorption was highly inversely correlated with the logarithm of load (P < 0.001). At the lowest loads, absorption averaged 64.0% and at the highest, 28.6%. The parameters of the best-fit relationship permit reasonably precise calculation of the impact of various calcium dosing and dietary strategies.
Bone status and fracture rates were evaluated in two Yugoslav populations with very different dietary habits. In district A (Podravina) the daily calcium intake was about twice that in district B (Istra). There were similar but smaller differences in the intakes of other nutrients. In district B metacarpal cortical width was reduced in all age groups of both sexes but the difference tended to decrease with age. The proximal femur fracture rate was higher in district B than district A but there was no difference between the forearm fracture rates in the two districts. Our results confirm that bone mass at any age is clearly the result of age and sex and most probably other genetically determined factors but also show that this expression is nutrition related. The data suggest that nutrition (in particular the calcium intake) is an important determinant of bone mass in young adults but seems to have little effect on age-related bone loss in either males or females. The main determinant of cortical bone mass in the elderly seems to be the cortical bone mass in middle life. The proximal femur fractures of old people reflect declining cortical bone mass but the distal forearm fractures of middle-aged women are unrelated to cortical bone mass or nutritional status.