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Dietary Calcium has recently been associated with weight loss. More
specifically, it may facilitate fat loss, excretion of dietary fat, the
reversal of gradual weight gain, the prevention of fat storage, raising
metabolism, increasing high density lipoproteins, and the reduction of
both kidney stones and symptoms of PMS. Plus it just may be more effective
than most common weight-loss drugs on the market today!
In a recent 16-week study, a very high calcium diet produced greater
weight loss than the average weight loss shown in one year in studies
using weight loss drugs. International Journal of Obesity & Related
Metabolic Disorders, Sept. 16, 2003
Robert Heaney, M.D., one of the foremost calcium and vitamin D researchers
states: “Only 1000 mg of additional calcium daily can result
in a 17.6 pound difference in your body weight.” Davies, KM,
Heaney RP, Recker RR, Lappe JM, Barger-Lux MF, Rafferty K, Hinders
S. Calcium intake and body weight. J Clin Endocrinol Metab. 2000 Dec;85(12):4635-8.
“Increasing calcium intake can be estimated to reduce the prevalence
of overweight by perhaps as much as 60 to 80 percent.” Heaney
RP. Normalizing calcium intake: projected population effects for body
weight. J Nutr. 2003 Jan;133(1):268S-270S.
CALCIUM & WEIGHT LOSS
The Experts Weigh In: Validation from Medical Journals
Currently, the weight-loss effect of calcium has been receiving a
great deal of attention. More exciting is that reliable scientific
research has been catching up with the observations:
A diet consisting mainly of high calcium foods resulted in an average
weight loss of 24.6 pounds in 16 weeks. This is greater than the average
weight loss in one year in trials using weight loss drugs such as
dexfenfluramine, sibutramine or orlistat. (Even if the drugs rivaled
the calcium diet for weight loss, they have serious side effects:
sibutramine increases blood pressure and pulse rate; orlistat causes
gastrointestinal side effects; and dexfenfluramine results in serious
respiratory and cardiovascular complications.) International Journal
of Obesity & Related Metabolic Disorders, Sep 16, 2003 / Hopkins
PN, Polukoff GI. Risk of valvular heart disease associated with use
of fenfluramine. BMC Cardiovasc Disord. 2003 Jun 11;3(1):5.
Test animals were placed on a diet high in sucrose and increased
fat, including lard. As anticipated, these animals quickly became
obese. But when given high levels of calcium, they stopped gaining
weight and, instead, began to lose weight. Even though the caloric
intake of the two sets of animals was identical, those on a low calcium
diet gained weight, while those on a high calcium diet lost weight.
Calcium helps to suppress a substance that would normally increase
adiposity (fat) with a calorie-dense meal. By increasing dietary calcium,
the result is a significant reduction in adipose tissue - accelerating
weight loss and body fat loss. Zemel MB . Role of dietary calcium
and dairy products in modulating adiposity. Lipids. 2003 Feb;38(2):139-46.
High-calcium, low-calorie diets helped test animals lose weight at
rates double those given low levels of calcium. Experimental Biology
2000, Conference, San Diego, April 21, 2000.
Overweight patients with high blood pressure were asked to consume
two cups of yogurt daily to increase their calcium intake in order
to lower their blood pressure. No other changes were made in their
diet or exercise routines. An average of 10.56 pounds was lost in
one year simply by adding the yogurt. Zemel MB , Shi H, Greer B, Dirienzo
D, Zemel PC. Regulation of adiposity by dietary calcium. FASEB J.
2000 Jun;14(9):1132-8.
A two-year study found that young women who had the highest intakes
of calcium lost the most weight and body fat on weight control programs,
regardless of exercise level. Lin YC, Lyle RM, McCabe LD, McCabe GP,
Weaver CM, Teegarden D. Dairy calcium is related to changes in body
composition during a two-year exercise intervention in young women.
J Am Coll Nutr. 2000 Nov-Dec;19(6):754-60.
Additional sophisticated peer-reviewed trials continue to indicate
that high-calcium diets are associated with lower body weight. And,
in a study published in the Journal of Nutrition, researchers estimated
that only 1,000 milligrams of additional calcium intake daily can
result in a 17.6 pound difference in your body weight. Davies KM,
Heaney RP, Recker RR, Lappe JM, Barger-Lux MJ, Rafferty K, Hinders
S. Calcium intake and body weight. J Clin Endocrinol Metab. 2000 Dec;85(12):4635-8.
Higher levels of calcium intake may prevent fat storage, and more
calcium may raise metabolism, thus burning more calories. Southwestern
Medical Center Report, 2003.
Each 300 mg increment in regular calcium intake is associated with
approximately 1 kg less body fat in children and 2.5-3.0 kg lower
body weight in adults. Increasing calcium intake could reduce the
risk of overweight substantially, perhaps by as much as 70 percent.
(1 kilogram is equal to 2.2 pounds.) Heaney RP, Davies KM, Barger-Lux
MJ. Calcium and weight: clinical studies. J Am Coll Nutr. 2002 Apr;21(2):152S-155S.
Calcium may play a role in increasing levels of high density lipoprotein
(HDL, the good kind), reducing kidney stone recurrence, reducing symptoms
of premenstrual syndrome, and promoting weight loss. Moyad MA. Osteoporosis.
Part III--Not just for bone loss: potential benefits of calcium and
vitamin D for overall gen eral health. Urol Nurs. 2003 Feb;23(1):69-74.
Women at midlife gain an average of about one pound a year (with
one-sixth of them gaining at the rate of 2.5 pounds a year) if they
are on low calcium intakes. By contrast, women who take the RDI amount
of calcium show a slight negative weight gain each year. Davies KM,
Heaney RP, Recker RR, Lappe JM, Barger-Lux MJ, Rafferty K, Hinders
S. Calcium intake and body weight. J Clin Endocrinol Metab. 2000 Dec;85(12):4635-8.
If you are overweight and not watching your diet, increasing dietary
calcium results in significant reductions in fat tissue, and if you
are on a calorie-restricted diet, the calcium will accelerate your
weight loss and body fat loss. Zemel MB . Role of dietary calcium
and dairy products in modulating adiposity. Lipids. 2003 Feb;38(2):139-46.
Growing evidence supports a relationship between increased calcium
intakes and reductions in body weight specific to fat mass. The impact
of calcium intake on weight loss or prevention of weight gain has
been demonstrated in a wide age range of Caucasian and African Americans
of both genders. Teegarden D. Calcium intake and reduction in weight
or fat mass. J Nutr. 2003 Jan;133(1):249S-251S.
Girls who consume more calcium tend to weigh less and have lower
body fat than those with low calcium consumption, although it is not
important whether the calcium comes from food or supplements. Experimental
Biology Meeting, San Diego, Oct 2003.
Low calcium diets impede body fat loss. Zemel MB . Role of dietary
calcium and dairy products in modulating adiposity. Lipids. 2003 Feb;38(2):139-46.
An increase in calcium consumption can reduce the risk of obesity.
International Obesity Symposium, Toronto, Sep 2003 / McCarty MF, Thomas
CA. PTH excess may promote weight gain by impeding catecholamine-induced
lipolysis-implications for the impact of calcium, vitamin D, and alcohol
on body weight. Med Hypotheses. 2003 Nov-Dec;61(5-6):535-42. / Moyad
MA. The potential benefits of dietary and/or supplemental calcium
and vitamin D. Urol Oncol. 2003 Sep-Oct;21(5):384-91.
Additional Selected Abstracts
Regulation of adiposity and obesity risk by dietary calcium: mechanisms
and implications
Zemel MB J
Am Coll Nutr. 2002 Apr;21(2):146S-151S.
Dietary calcium plays a pivotal role in the regulation of energy
metabolism; high calcium diets attenuate weight gain during periods
of overconsumption and preserve thermogenesis during caloric restriction,
thereby markedly accelerating weight loss... Moreover, we have recently
demonstrated that the increased calcitriol released in response to
low calcium diets stimulates Ca2+ influx in human adipocytes and thereby
promotes adiposity. Accordingly, suppressing calcitriol levels by
increasing dietary calcium is an attractive target for the prevention
and management of obesity... Further, low calcium diets impede body
fat loss, while high calcium diets markedly accelerate fat loss in
transgenic mice subjected to caloric restriction. These findings are
further supported by clinical and epidemiological data demonstrating
a profound reduction in the odds of being obese associated with increasing
dietary calcium intake.
Low calcium intake: the culprit in many chronic diseases (ADSA
Foundation Lecture)
Heaney RP, Barger-Lux MJ.
J Dairy Sci. 1994 May;77(5):1155-60.
...Moreover, the natural diets of all mammals are rich in calcium.
The diet of Stone Age human adults is estimated to have contained
from 50 to 75 mmol of calcium (2000 to 3000 mg)/d, three to five times
the median calcium intake of present-day US adults... At least 14
intervention studies have established the skeletal benefit of increased
calcium intake during growth and among women in the late postmenopause...
The role of calcium intake in preventing bone fragility, hypertension,
and certain cancers
Barger-Lux MJ, Heaney RP.
J Nutr. 1994 Aug;124(8 Suppl):1406S-1411S.
This paper examines the evidence that connects calcium intake and
vitamin D status to bone fragility, hypertension, colon cancer, and
breast cancer. Human calcium physiology, with an intestinal absorptive
barrier and inefficient conservation, reflects the abundance of calcium
in the primordial human food supply... Long-term calcium restriction
and/or insufficient vitamin D may promote the development of bone
fragility, high blood pressure, colon cancer, and breast cancer in
susceptible individuals...
Calcium supplements: practical considerations
Heaney RP.
Osteoporos Int. 1991 Feb;1(2):65-71.
The preferable source of calcium is a balanced diet, but medicinal
supplements are sometimes necessary if patients are to reach desired
intakes. A divided dose regimen (4x/d; i.e., with meals and at bedtime)
results in substantially greater absorption of a supplement than does
1x/d dosing... Because typical patients exhibit a wide range of absorption
efficiencies, it is desirable to assess absorption fraction before
beginning a supplement regimen. (Some patients will need three times
as large a dose as others to absorb the same amount of calcium.) Calcium
intakes up to at least 62.5 mmol (2500 mg) are safe for virtually
all patients. (note: study excluded sodium-insensitive hypertension
patients, etc.)
Calcium, dairy products and osteoporosis
Heaney RP.
J Am Coll Nutr. 2000 Apr;19(2 Suppl):83S-99S.
...Of 52 investigator-controlled calcium intervention studies, all
but two showed better bone balance at high intakes, or greater bone
gain during growth, or reduced bone loss in the elderly, or reduced
fracture risk. This evidence firmly establishes that high calcium
intakes promote bone health... While most of the investigator-controlled
studies used calcium supplements, six used dairy sources of calcium;
all were positive. Most of the observational studies were based on
dairy calcium also, since at the time the studies were done, higher
calcium intakes meant higher dairy intakes... All studies evaluating
the issue reported substantial augmentation of the osteoprotective
effect of estrogen by high calcium intakes... (note: there are some
extensive recent studies that find that milk does not protect the
skeletal system.)
Calcium needs of the elderly to reduce fracture risk.
Heaney RP
Creighton University, Osteoporosis Research Center.
...Supplemented intakes to a total in the range of 32.5-42.5 mmol
(1300-1700 mg)/day have been shown to arrest age-related bone loss
and to reduce fracture risk in individuals 65 and older and intakes
of 60 mmol (2400 mg), to restore the setting of the parathyroid glands
to young adult values... Accordingly, suppressing calcitriol levels
by increasing dietary calcium is an attractive target for the prevention
and management of obesity...
The cellular ionic basis of hypertension and allied clinical conditions.
Resnick L
Prog Cardiovasc Dis. 1999 Jul-Aug;42(1):1-22.
...a unifying "ionic hypothesis" is proposed, in which
steady-state elevations of cytosolic free calcium and suppressed intracellular
free magnesium levels, characteristic features of all hypertension,
concomitantly alter the function of many tissues. In blood vessels
this causes vasoconstriction, arterial stiffness, and/or hypertension;
in the heart, cardiac hypertrophy; in platelets, increased aggregation
and thrombosis; in fat and skeletal muscle, insulin resistance; in
pancreatic beta cells, other endocrine tissues, and sympathetic neurons,
potentiated stimulus-secretion coupling resulting in hyperinsulinemia,
increased sympathetic nerve activity, and so on...
New Key Study!
Effect of short-term high dietary calcium intake on 24-h energy
expenditure, fat oxidation, and fecal fat excretion
Jacobsen R, Lorenzen JK, Toubro S, Krog-Mikkelsen I, Astrup A.
Int J Obes Relat Metab Disord. 2005 Mar;29(3):292-301.
Observational studies have shown an inverse association between dietary
calcium intake and body weight, and a causal relation is likely. However,
the underlying mechanisms are not understood... 10 subjects participated
in a randomized crossover study of three isocaloric 1-week diets with:
low calcium and normal protein (LC/NP: 500 mg calcium, 15% of energy
(E%) from protein), high calcium and normal protein (HC/NP: 1800 mg
calcium, 15E% protein), and high calcium and high protein (HC/HP:
1800 mg calcium, 23E% protein). RESULTS: The calcium intake had no
effect on 24-h EE or fat oxidation, but fecal fat excretion increased
approximately 2.5-fold during the HC/NP diet compared with the LC/NP
and the HC/HP diets (14.2 vs 6.0 and 5.9 g/day; P < 0.05). The
HC/NP diet also increased fecal energy excretion as compared with
the LC/NP and the HC/HP diets (1045 vs 684 and 668 kJ/day; P < 0.05).
There were no effects on blood cholesterol, free fatty acids, triacylglycerol,
insulin, leptin, or thyroid hormones. CONCLUSIONS: A short-term increase
in dietary calcium intake, together with a normal protein intake,
increased fecal fat and energy excretion by approximately 350 calories
per day. This observation may contribute to explain why a high-calcium
diet produces weight loss, and it suggests that an interaction with
dietary protein level may be important.
2005 Study on Calcium & Reduced Colorectal Cancer: Calcium
from diet and supplements is associated with reduced risk of colorectal
cancer in a prospective cohort of women
Flood A, Peters U, Chatterjee N, Lacey JV Jr, Schairer C, Schatzkin
A.
Cancer Epidemiol Biomarkers Prev. 2005 Jan;14(1):126-32.
We investigated the association between calcium intake and colorectal
cancer in a prospective cohort of 45,354 women without a history of
colorectal cancer who successfully completed a 62-item National Cancer
Institute/Block food-frequency questionnaire. Women were followed
for an average of 8.5 years, during which time 482 subjects developed
colorectal cancer. We used Cox proportional hazards models, with age
as the underlying time metric, to estimate risk of colorectal cancer...
For increasing categories of calcium from supplements, the risk ratios
(and 95% CI) relative to no supplement use were 1.08 (0.87-1.34),
0.96 (0.70-1.32), and 0.76 (0.56-1.02), P(trend) = 0.09. Simultaneously
high consumption of calcium from diet and calcium from supplements
resulted in even further risk reduction, RR = 0.54 (95% CI, 0.37-0.79)
compared with low consumption of both sources of calcium. These data
indicate that a difference of < 400 to > 800 mg of calcium per
day was associated with an approximately 25% reduction in risk of
colorectal cancer, and this reduction in risk occurred regardless
of the source of the calcium (i.e., diet or supplements)
Abstract of Negative Findings:
Effect of calcium and dairy foods in high protein, energy-restricted
diets on weight loss and metabolic parameters in overweight adults.
Bowen J, Noakes M, Clifton PM.
Int J Obes Relat Metab Disord. 2005 Feb 15; [Epub ahead of print]
OBJECTIVE: To compare the effects two high-protein (HP) diets that
differ in dietary calcium and protein source on weight loss, body
composition, glucose and lipid metabolism, markers of liver function,
fibrinolysis and endothelial function and blood pressure. DESIGN::
Randomized, parallel study (12 wk of energy restriction, 4 wk of energy
balance) of high dairy protein/high-calcium (DP, 2400 mg Ca/d) and
high mixed protein/moderate calcium (MP, 500 mg Ca/d) diets (5.5 MJ/d,
34% protein, 41% carbohydrate, 24% fat). SUBJECTS:: In all, 50 healthy,
overweight (age 25-64 y; body mass index 25-35 kg/m(2);) males (n=20)
and females (n=30). RESULTS:: Loss of total weight (-9.7+/-3.8 kg),
fat mass (-8.3+/-0.4 kg) and lean mass (-1.6+/-0.3 kg) were independent
of dietary group. Improvements in fasting insulin, lipids, systolic/diastolic
blood pressure, and markers of liver function, fibrinolysis and endothelial
function were independent of dietary intervention. CONCLUSIONS:: Increased
dietary calcium/dairy foods in an energy-restricted, HP diet does
not affect weight loss or body composition. Weight reduction following
increased protein diets is associated with beneficial metabolic outcomes
that are not affected by protein source.
Editor's Comment: In our opinion, high protein diets would
mitigate against calcium's weight loss effects as explained and demonstrated
in the Jacobson, et al. abstract. The difference reported for the
normal protein diet versus the high protein diet was attributable
to a fecal fat and energy excretion of 350 calories per day.
Calcium critics* must consider the large scale calcium deficiencythat
exists across various populations
Calcium Deficiency Firmly Established
KELLEY'S TEXTBOOK OF INTERNAL MEDICINE
Osteopenia (loss of bone density) is a very common and costly disorder
in the United States that affects 25% of elderly women and, at a given
age, half as many men as well. The cause is multifactorial, with several
nutritional factors playing important roles in calcium balance. Almost
all nutritional surveys indicate that calcium intake in the elderly
is far less than the RDA (which was recently increased from 800 mg
to 1,200 mg for persons over age 50). Still higher intakes of 1,500
mg per day were recommended for men and women over age 65 by a 1994
National Institutes of Health consensus panel on optimal calcium intake.
The NHANES II study found mean calcium intakes of 596 and 475 mg per
day in older men and women, respectively, and NHANES III found that
virtually all elderly had intakes below 800 mg per day. Calcium intake
is also inadequate in younger women, with 66% of women 18 to 30 years
old and 75% older than 35 years similarly consuming less than 800
mg per day. Reduced consumption at these early ages may be critical
because peak bone mass is attained during early adulthood. Of interest,
a recent large randomized trial found that supplemental calcium (1,200
mg per day) also decreased the risk of colorectal adenomas, providing
another potential rationale for calcium supplementation beyond its
beneficial effects on bone. Absorption of calcium supplements appears
to be most efficient at individual elemental calcium doses of 500
mg or less and when taken between meals (except for persons with reduced
gastric acid production, in whom calcium citrate may be preferable
to more commonly used calcium carbonate supplements).
Kelley's Textbook of Internal Medicine, Fourth Edition, Chapter 470,
pg.3111, Lippincott Williams & Wilkins, 2000.
Normalizing Calcium Intake: Projected Population Effects for Body
Weight
Robert P. Heaney
American Society for Nutritional Sciences, 2003, p. 268S-270S
Discussion Excerpts: The data presented in this analysis suggest
that the prevalence of obesity (or weight gain) in women could be
reduced by 60-80% by the simple strategem of ensuring population-wide
calcium intakes at the currently recommended levels...
...Also reassuring in this regard is the analysis of the NHANES-III
data earlier reported by Zemel, et al.(1) After adjusting for age,
sex, race and energy intake, they found a stepwise reduction in risk
of obesity for each quartile of calcium intake. At the highest quartile
(approximately equal to current recommendations for calcium), the
risk of being in the highest BMI quartile was reduced by about 80%...
...The observation, both evident here and previously noted (2), that
mean weight gain at midlife is effectively zero if calcium intake
is at currently recommended levels is a fortuitous confirmation of
the approximate adequacy of those recommendations. It is fortuitous
in the sense that the currently recommended intakes were pegged to
a skeletal endpoint, and there is no prior reason to expect that all
systems would exhibit the same requirement. It is also interesting
to note that, despite the established bone protective benefit of an
adequate calcium intake, the data presented here suggest that the
effect on obesity prevalence-unrecognized until recently - is likely
to be as large as, or larger than, the corresponding effect on osteoporosis
prevalence...
... Low calcium intakes in this case are so widespread in the North
American population today that virtually everyone is exposed to that
influence. If, as seems increasingly likely, these low intakes are
inadequate, then correcting calcium intake at a population level would
produce benefits for many body systems. Furthermore, some of the factors
currently considered to be causative of the diseases concerned will
likely turn out to be only predisposing or triggering factors, operating
by exaggerating or uncovering the effects of the real cause, inadequate
calcium intake.
1. Zemel MB, Shi H, Greer B, Dirienzo D, Zemel PC. Regulation of
adiposity by dietary calcium. FASEB J. 2000 Jun;14(9):1132-8.
2. Heaney RP, Davies KM, Barger-Lux MJ. Calcium and weight: clinical
studies. J Am Coll Nutr. 2002 Apr;21(2):152S-155S.
*We have found that some of the leading authorities in nutrition
are against calcium supplementation.
Editor's Note on Calcium Supplementation
Of all the ideological conflicts in nutritional medicine, one area
where there is huge disagreement is whether to supplement with calcium
or not.
Leaders and opinion makers I respect have criticized supplementation
of additional calcium despite increasing RDA's and dozens of studies
showing benefits for osteoporosis prevention. Evidence exists that
higher intakes of calcium minimize expression of such conditions as
cancer of the colon and breast, and hypertension and obesity, all
of which are multifactorial in causation and have a calcium deficiency
component. The higher RDA's are a result of studies showing that higher
levels are required to maintain calcium balance. J. Nutrition. 133:
249S-251S 2003
If we go back to the very basic issues, calcium deficiency is firmly
established, as summarized from Kelley's Textbook of Internal Medicine
(Fourth Edition, Chapter 470, pg. 3111, 2000) as presented on page
8. We are a population deficient in calcium, as defined by federal
based requirements. It is one of the most significant nutritional
deficiencies that exist. Other paramount nutritional deficiencies
that are talked about here include vitamin D, magnesium and vitamin
K, especially vitamin K2. Since all of these nutrients work together
to optimize calcium biochemistry, and since calcium is such a critical
structural and regulatory molecule, functional problems associated
with deficiencies are likely be much greater, as clinical effects
are compounded by multiple deficiencies of these related nutrients.
The odds are that most of us are deficient in one or more of these
nutrients.
Why do we need so much calcium when other cultures don't? There are
some other cultures that exhibit much lower calcium consumption and
lower osteoporosis? Our culture wastes calcium via high protein, high
phosphorus and acidifying diets. These are big factors and cannot
be overlooked. Jaffe R, Brown S. Acid-Alkaline ba lance and its effect
on bone health. Intl J Integrative Med, 2001; 4 (6): 7-18.
Also, our consumption of pasteurized milk, being our major food source
of calcium, may exaggerate magnesium deficiency because the ratio
of calcium to magnesium is so high at 9:1. As I will show, magnesium
deficiency compromises some of calcium's function, so milk may be
worsening both calcium and magnesium deficiency in some patients.
There are also recent findings that suggest that milk may not be the
best source of calcium for healthy bones, as seen in the Nurse's Study
done at Harvard, although numerous other studies show benefit for
bones.
So why are leading orthomolecular doctors, who are opinion leaders,
and internationally-known authoritative figures, anti-calcium or let's
say, calcium antagonists? Because these doctors are concerned about
calcium accumulation in the vascular system and in soft tissues over
many years, and they blame dietary calcium. Also, these doctors are
well aware of the vast magnesium deficiencies that exist and are afraid
that supplemental calcium will compete with magnesium for absorption.
I will quote from the very prestigious textbook Modern Nutrition
in Health and Disease (9th Edition, edited by Maurice Shils, James
Olson, Moshe Shike, Catherine Ross. 1999, Lippincott Williams & Wilkins).
(All quoted text is italicized.)
With advancing age, humans commonly accumulate calcium deposits in
various damaged tissues, such as atherosclerotic plaques in arteries,
healed granulomas, and other scars left by disease or injury, and
often in the rib cartilages as well. These deposits are called dystrophic
calcifications and rarely amount to more than a few grams of calcium.
These deposits are not caused by dietary calcium, but by local injury,
coupled with widespread tendency of proteins to bind to calcium.
Our opinion is that higher dietary calcium, via the calcium paradox,
and magnesium and other minerals such as boron, and especially vitamin
K, will prevent much of the dystrophic calcification.
Calcification, which usually occurs intracellularly in tissues other
than bones and teeth is generally a sign of tissue damage, cell aging
and cell death. As cells lose control of calcium regulation and are
unable to maintain low intracellular calcium, cellular function must
degenerate.
It is worth explaining that calcium binds to a large number of cell
proteins, which result in the activation of their function. By binding
with oxygen atoms of glutamic acid and aspartic acid residues projecting
from the peptide backbone, calcium stiffens the protein molecule and
fixes its tertiary structure. Hence the cell keeps cytoplasmic concentration
very low, and when it wants to activate these calcium-associated enzymes,
it allows calcium to enter and uses calcium in a regulatory manner.
When calcium generally "leaks" into cells it means the cells
are sick and failing to regulate calcium and this will initiate a
further loss of function of the cell.
These calcium-associated proteins range from those involved in cell
movement and muscle contraction to nerve transmission, glandular secretion,
and even cell division. In most of these situations calcium acts as
both a signal transmitter from the outside of the cell to the inside,
and an activator of the functional proteins involved. In fact, ionized
calcium is the most common signal transmitter in all of biology. It
operates from bacterial cells all the way up to cells of highly specialized
tissues in higher mammals.
There is concern that high calcium intake would produce relative
magnesium deficiency, and this has been observed in rats but not humans.
Calcium intake does not affect magnesium retention in humans. However
the reverse, hypocalcemia, can occur as a result of magnesium deficiency.
(Summarized in Shils, et al., Modern Nutrition in Health and Disease,
1999.)
Hypercalcemia refers to an elevation of calcium in blood and is generally
reported wherein there is large consumption of calcium to raise the
pH in peptic ulcer disease, but not for the normal diet. In Africa,
the nomadic pastoral Masai tribe diet consists mostly of milk from
the herds and flocks, and they consume 5000 mg of calcium per day
or more, which is 5 or more times what the industrial population consumes.
The Masai tribe are not known to have unusually high incidence of
hypercalcemia or kidney stones. (Shils, et al., Modern Nutrition).
They probably have another good source of magnesium.
The theory presented by Heaney and others that prehistoric man consumed
a lot of calcium is also presented in the Shils text and referenced
to in Eaton's New England Journal of medicine article. (Eaton SB,
Konner M. N. England J. Med. 1985:312 283-289) Therein it is stated
that:
Early man derived calcium from roots, tubers, nuts, and beans in
quantities believed to exceed 1500 mg per day, and perhaps twice this
amount when consuming food to meet the caloric demands of a hunter/gatherer
of contemporary body size.
Such a well-known text and nutritional source as Modern Nutrition
presents generally accepted nutritional concepts which must be accepted
by a wide range of experts. So their opinions represent a consensus
of academic thinking. In these cases, the concepts generally agree
with the citations from Dr. Westin Price's work, the Okinawa program
by Willcox B, Willcox C, and Suzuki M., and the theoretical and research
conclusions from a host of other researchers presented in this newsletter.
The health benefits of pasteurized milk have become highly questioned
due to significant research correlations with cardiovascular risk,
prostate cancer, MS, bovine leukemia virus and more. The exact cause
is still uncertain, but proteins altered by the heat of pasteurization
and other potential causes are cited. Raw milk and yogurts are probably
better choices. It is interesting to note that much of civilization
grew up surrounded by flocks of goats and other milk-bearing animals.
Such animals have fed hungry families for millennium, and our genetic
constitution must have adjusted to some degree. (The Untold Story
of Milk, Ron Schmid, N.D., 2003, NewTrends Publishing).
Calcium critics should probably direct their concerns towards commercial
milk and milk products rather than the calcium they contain.
Responses to Common Criticisms of Calcium Supplementation:
Criticism: None of the studies strongly support calcium supplements
as contributing to weight loss. They do support dairy calcium, meaning
calcium found in non-fat diary.
Response: The original study was made when yogurt was added
to the diet of hypertensive patients with no other dietary changes.
On average, over 10 lbs was lost by participants in one year. These
results lead to an interest in calcium and weight loss. Shortly afterwards,
animal studies in which calcium was increased from .1% to 2% resulted
in a reduced weight gain in both lean and overweight Zucker rats.
Extensive biochemistry studies followed to delineate the mechanism
involved. Both calcium from milk products and calcium salts were used
(summarized in Calcium Intake and Reduction in Weight or Fat Mass,
Mass J. Nutr. 33: 249S-251S 2003). In a two year study, mineral bone
mass was tested. 54 women completed a two year trial. Calcium intakes
were low, 781+- 212 mg per day, compared to dietary reference of 1000
mg per day. The primary calcium source was dietary calcium from dairy
(67%). Dietary calcium ratio to energy (calories) negatively predicted
changes in body weight and body fat, but not for lean mass. This means
the more calcium, the less fat accumulated without reductions in protein
levels. Dairy calcium predicted the changes as well as did non-dairy
calcium; the research on fat storing enzymes and alterations in body
temperature by calcium works independent of the source of calcium.
Another very important point is that this relationship of lowered
body weight to calcium intake occurs in low, but not high calorie
diets.
"Calcium intake did not predict changes in weight or fat
mass in the group with calorie intakes above the mean. On the other
hand calcium, but not calories, negatively predicted changes in
weight and fat mass in calorie intakes below the mean."
So you can't stuff yourself and expect calcium to protect you. This
indicates that one should be moderate in food consumption in order
to get calcium to work for your biochemistry.
"Clearly if dairy products are added to a diet without compensation
for energy intake, one is likely to gain weight."
We would like to emphasize that this is not a magic bullet for immediate
weight loss, but a long term solution which may generally aid patients
to gain advantage over the slow weight gain that accompanies aging.
Calcium could turn around that increase in girth, when consumed with
a moderate diet, and even turn that to a slight weight loss, according
to the researchers we cite.
However, aggressive interventions as described on page 1 might be
tried under medical supervision, and may produce dramatic results
as the study cited, with a milk diet.
Also, notable benefit may follow the use of a highly buffered form
of calcium, magnesium and potassium formula in relationship to food
cravings.
Criticism: The low incidence of obesity in ancient people
and underdeveloped countries is directly proportional to activity
levels and lack of food or lack of refined food.
Response: There are obviously many factors and exercise is
certainly got to be a big one. The calcium effect is a statistical
factor. We have tried to emphasize that by relying on some of the
analysis in the abstracts. Not everyone will respond and this is a
long term potential solution of potentially great magnitude. Also,
one might appreciate OUR model that winter brings hibernation in hibernating
animals. I suspect that we (humans) also have some of those hibernation
characteristics. Perhaps because not enough vegetables and other rich
sources of dietary calcium are being consumed, and less time is spent
in the sun, humans may have retained the ability to conserve reserves
by reducing fat burning, thereby conserving energy in the form of
fat "for a sunny day" or for the spring and summer season.
Just as the old adage goes, normally we save our resources "for
a rainy day" and the body does the same by conserving fat and
reducing fat burning when sunshine and calcium (a marker for vegetable
consumption) are in short supply. There is data that vitamin D also
has an inverse relationship to obesity. Hence, lack of vegetables
(high in calcium) and sunshine would signal the body to go into a
modified hibernation mode, slowing down metabolism for the winter
season. So that's our hibernation theory.
We have presented expert "textbook" opinions on the safety
of calcium supplementation, along with the probable explanation of
the calcium paradox and clinical benefits from higher levels. However,
more needs to be said on safety.
Certain medical conditions might be related to or worsened by increased
dietary calcium, but this is not clear from the literature from what
we have seen. It is plausible that in patients with renal failure
there could be preferential mineralization in vascular tissue instead
of bone. Kidney failure, as with other serious illness may require
special consideration on a case by case basis. In other disease states,
abnormal calcification of vessels and tissues as described in complex
animal studies by Hans Selye ( Calciphylaxis, 1962, The University
of Chicago Press) may occur, but again we think the weight of the
evidence by far, suggests safety and benefit for RDA, and even somewhat
higher levels for the general population.
Since we have presented statistical findings, we cannot appropriately
determine which patients will respond. It is likely that a portion
will not respond and this may well be related to metabolic type. Since
some significant groups may not respond, the data for those that do
respond would thus be understated, because it would represent average
numbers (per individual). Hence a more profound response might be
expected from responders. |
