So what’s the deal with calcium and weight loss? There are a few studies out there that show some kind of link between calcium and fat loss — with caveats, of course.
A small study found that obese women participating in a weight loss program who were calcium deficient lost more than 13 pounds after taking daily calcium supplements, compared to the control group, which lost a little over two pounds in the control group.
A review of studies on the link between dietary calcium intake and body weight suggests that calcium seems to bind more fatty acids in the intestines, thereby inhibiting the absorption of some fats. The review concluded that “calcium and dairy food intake can influence many components of energy and fat balance.”
Calcium is the most abundant mineral in the body. 99% of the body’s calcium supply is stored in the bones and teeth, where it supports their structure and function. We ingest calcium from foods such as dairy, green leafy vegetables, and fortified foods (such as non-dairy milk, juice, and cereal).
We can also find calcium in some medications, like antacids, as well as in supplemental form. However, it is best to receive your daily calcium intake through foods that are naturally rich in calcium whenever possible.
The body needs calcium to maintain strong bones and to carry out many important functions. Almost all calcium is stored in bones and teeth, where it supports their structure and hardness.
The body also needs calcium for muscles to move and for nerves to carry messages between the brain and every body part. In addition, calcium is used to help blood vessels move blood throughout the body and to help release hormones and enzymes that affect almost every function in the human body.
Diets high in fermentable fibers (usually found in vegetables) and high enough in bulk and fiber to slow the rate at which food passes through the intestines increase calcium absorption; simply taking a calcium supplement on top of a low fiber/low bulk diet will not be as effective as consuming the calcium through dairy or even vegetables.
Calcium’s leading role is legendary. In fact, there seems to be no end to calcium’s repertoire: It strengthens bones and teeth and new studies suggest that it may also prevent colon cancer, and even keep Montezuma’s revenge at bay.
There’s also good evidence that diets high in calcium are associated with reduced rates of being overweight or obese.
“At midlife, women tend to gain one-quarter to one-half a pound per year whether they want it or not, and it all goes to their waist,” says Robert Heaney, MD, an internationally recognized expert in bone biology and calcium nutrition with Creighton University in Nebraska.
“We’ve found that women with the highest dairy intake have an average weight gain of zero, and those with the lowest dairy intake gained a pound per year,” Heaney tells WebMD
Several studies have correlated higher calcium intakes with lower body weight or less weight gain over time [57-61]. Two explanations have been proposed. First, high calcium intakes might reduce calcium concentrations in fat cells by decreasing the production of parathyroid hormone and the active form of vitamin D. Decreased intracellular calcium concentrations, in turn, might increase fat breakdown and discourage fat accumulation in these cells . Second, calcium from food or supplements might bind to small amounts of dietary fat in the digestive tract and prevent absorption of this fat [59,62,63]. Dairy products, in particular, might contain additional components that have even greater effects on body weight than their calcium content alone would suggest [60,64-67]. For example, protein and other components of dairy products might modulate appetite-regulating hormones .
Taking calcium can slow bone loss in women after menopause and in elderly men. This can reduce the risk of breaking bones.
Calcium can also decrease the symptoms of premenstrual syndrome (PMS), especially mood swings, bloating, food cravings, and pain.
There is also some evidence that calcium might lower the risk of getting colon cancer, especially among people who have already had small, noncancerous intestinal growths called “polyps.”
Calcium also seems to be able to lower high blood pressure, especially in people with kidney disease or in pregnant women.
Taking calcium does not seem to be effective, however, in preventing bone loss in breast-feeding women, or after kidney or bone marrow transplants.
Several studies have suggested that taking calcium supplements might improve metabolic markers, especially when taken with vitamin D.
In a 2016 study, 42 pregnant women took supplements containing calcium and vitamin D. Several of their metabolic markers improved, including blood pressure and markers of inflammation (9Trusted Source).
Other research has shown that the children of women who took calcium supplements while pregnant have lower blood pressure at age seven than the children of mothers who did not take them (10Trusted Source).
In a recent study, more than 100 overweight, vitamin D-deficient women with polycystic ovary syndrome (PCOS) were given either a calcium and vitamin D supplement or placebo pill.
There is evidence suggesting that cardiovascular disease might be protected by calcium supplementation. A prospective cohort study conducted among an elderly Chinese population indicated that dietary calcium intake (mean =600 mg/d) could reduce the risk of death from all causes and cardiovascular diseases.34 Despite the limitations (a self-administered questionnaire was used), its results added to the body of evidence that calcium supplementation decreases the mortality risk of cardiovascular diseases. Another prospective cohort study in Europe indicated that a daily administration of a mean of 820 mg dietary calcium has an effect of up to a 30% decrease in the risk of myocardial infarction.35
The effect of dietary calcium intake on the colorectal cancer and a comparison with the effect of higher and lower level of dietary calcium have been investigated by Galas et al.44 They concluded that an increase of 100 mg dietary calcium intake per day lowered by 5% the risk of colorectal cancer (OR =0.95, 95% CI =0.92–0.99), and an increase of 1,000 mg/d dietary calcium consumption decreased incidence by 37% of colorectal cancer and the risk of colon cancer by 50%. Simultaneously, dietary calcium >1,000 mg/d decreased 46% incidence of colon cancer by 46% and the risk of colorectal cancer by 30%.44 A prospective cohort study revealed that the greatest benefits were observed with subjects who had highest dietary calcium intake (median =914 mg/d) compared with subjects who had lowest calcium intakes at a median level of 486 mg/day.45
Studies suggest that doses exceeding 4,000 mg have been associated with many health risks.
Some individuals who take calcium supplements even within the recommended amounts may still experience side effects including gas, bloating, constipation, or a combination of these symptoms. It has been suggested that calcium carbonate is more likely to cause these symptoms over calcium citrate.
Efforts to reduce symptoms include spreading doses of calcium throughout the day and taking calcium with meals.
Additionally, when calcium supplementation is excessive, it can cause high levels of calcium in the blood in a condition known as hypercalcemia. Hypercalcemia can cause renal insufficiency, vascular and soft tissue calcification, hypercalciuria (high levels of calcium in the urine), and kidney stones.
Some patients report gastrointestinal symptoms, such as bloating, constipation, gas, or a combination of all three. Calcium citrate usually has fewer and less pronounced side effects than calcium carbonate. Taking the supplements with food, or spreading their intake throughout the day sometimes helps reduce the occurrence or intensity of the side effects.
Calcium supplements come in different forms, including tablets, capsules, chews, liquids and powders.
One key difference between these types of supplements is the form of calcium they contain.
The two main forms are:
- Calcium carbonate
- Calcium citrate
These two forms differ in how much elemental calcium they contain and how well they’re absorbed. Elemental calcium refers to the amount of calcium that is present in the compound.
The Institute of Medicine has set Dietary Reference Intakes (DRI) and Recommended Daily Allowances (RDA) for calcium. Getting this amount from diet, with or without supplements, may be enough to keep your bones healthy. Doctors may recommend higher doses.
|0-6 months||200 mg/day|
|7-12 months||260 mg/day|
|1-3 years||700 mg/day|
|4-8 years||1,000 mg/day|
|9-18 years||1,300 mg/day|
|19-50 years||1,000 mg/day|
|51- 70 years||1,200 mg/day (women) 1,000 mg/day (men)|
|70+ years||1,200 mg/day|
Women who are pregnant or breastfeeding do not need extra calcium beyond the recommendations above.