Contrary To Popular Belief, Dietary Calcium Does Not Prevent Bone Loss
Dairy products, specifically milk is one of the beverages still aggressively pushed as a health promoting food, especially relating to strong bones. However, Bone Mineral Density (BMD) and rates of bone loss showed no association with dietary calcium intake in men, according to a recent study in British Journal of Nutrition.
The dairy industy has been hard at work the last 50 years convincing people that pasteurized dairy products such as milk or cheese increases bioavailable calcium levels. Many studies have exposed this claim as being totally false. The pasteurization process only creates calcium carbonate, which has absolutely no way of entering the cells without a chelating agent. So what the body does is pull the calcium from the bones and other tissues in order to buffer the calcium carbonate in the blood. This process actually causes osteoporosis.
Pasteurized dairy contains too little magnesium needed at the proper ratio to absorb the calcium. Most would agree that a minimum amount of Cal. to Mag Ratio is 2 to 1 and preferably 1 to 1. So milk, at a Cal/Mag ratio of 10 to 1, has a problem. You may put 1200 mg of dairy calcium in your mouth, but you will be lucky to actually absorb a third of it into your system.
Over 99% of the body’s calcium is in the skeleton, where it provides mechanical rigidity. Pasteurized dairy forces a calcium intake lower than normal and the skeleton is used as a reserve to meet needs. Long-term use of skeletal calcium to meet these needs leads to osteoporosis.
For years, US guidelines have advised men and women to take anywhere from 1,000 to 1,200 mg of calcium per day to help prevent fractures and improve bone density. This likely lasted for so long due to an overreliance on studies from the 1970s and 1980s.
Increased dietary calcium intake did not significantly reduce bone loss in the hip, spine or total body in a group of men aged 39-88, reported the research team from University of Auckland.
No correlation was observed between calcium intake and BMD either at baseline, or at the end of the study period. Although dietary calcium intake was inversely related to parathyroid hormone (PTH) levels at baseline, indicators of bone turnover were uncorrelated with calcium intake.
“Bone loss over 2 years was not related to Ca intake at any site, before or after adjustment [forconfounding variables],” wrote first author, Dr. Sarah Bristow.
“Dietary calcium intake was inversely correlated with PTH at baseline, but was not associated with the markers of bone turnover.”
The findings may have important implications for osteoporosis prevention strategies, where increased dietary or supplemental calcium intake has previously been recommended.
“This suggests that efforts to increase calcium intake are unlikely to have an impact on the prevalence of and morbidity from male osteoporosis,” the researchers propose.
“Many of the messages being promulgated at the present time are based on the findings of calcium-balance studies and the short-term effects of high-dose calcium interventions, which do not reflect those of long-term dietary intake.
“Messages to increase dietary calcium could be directing at-risk individuals away from considering interventions and strategies proven to influence long-term fracture risk.”
The study used data from a previous Randomised Controlled Trial (RCT) which examined the effect on BMD in 323 males given either 1200 milligrams/day (mg/d), 650 mg/d or placebo of calcium over two years. Data from the placebo group (n=99) were used in longitudinal analysis.
Although the earlier RCT found that the 1200 mg/d dose improved BMD by around 1%, this effect was achieved in the first 6 months, with no further subsequent improvement in the remaining 18 months.
These results prompted the researchers to hypothesise that short-term calcium intakes from high-dose calcium interventions are unrepresentative of longer-term dietary intake. The findings of the recent longitudinal study support this hypothesis.
They are also consistent with previous research indicating a similar lack of association between calcium intake and bone loss in women.
The researchers suggested the lack of association between calcium intake and BMD might be because the body is able to maintain calcium homeostasis over (long-term) typical dietary ranges (415-1740 mg/d).
Observational study findings appear to contradict supplementation RCTs, which have shown small increases in BMD, coupled with reductions in PTH and bone turnover. However, BMD improvements identified in RCTs have only occurred in the first year with no further cumulative effect.
This may be because short-term high doses of calcium induce a temporary reduction in bone turnover, which does not persist once steady-state calcium homeostasis is restored, suggested the researchers.
“Collectively, evidence from intervention and observational studies suggests long-term calcium intake doesn’t influence the rate of bone loss, but large increases in calcium intake induce a transient change,” they wrote.
The scientists emphasised that the study was conducted in Caucasian males with adequate vitamin D status. Therefore, results may not be applicable to other ethnic groups or those with vitamin D deficiency.
“The present demonstration of an absence of an effect of dietary calcium intake on current bone mass or on bone loss in normal men, together with the absence of an effect of calcium intake on bone turnover, contributes to the body of evidence suggesting that calcium intake, within the range studied here, is not a critical factor in the maintenance of bone health in older adults” the authors concluded.
6 WAYS TO BUILD STRONG BONES
1. Eat calcium rich foods
Eat foods high in calcium. The best food sources are non-pasteurized raw dairy sources such as raw milk/yogurt, as well as bony fish, such as sardines. Leafy green veg such as kale, broccoli and spinach are also rich in calcium. Dried herbs and dried fruits such as figs and currants are also good choices. Seeds such as sesame, chia and flax are also rich sources of calcium. Also, enjoy foods that contain sulfur such as garlic and onions.
2. Food selections/combinations are critical
Try not to eat whole grains and calcium-rich foods at the same time. Whole grains contain a substance that binds with calcium and prevents proper absorption. Some foods that contain compounds such as oxalic or phytic acids, such as sweet potatoes, beans, rhubarb, celery and beets, can also decrease the amount of calcium that’s absorbed when eaten at the same time as calcium-rich foods.
3. Avoid the causes of mineral excretion
Pass on phosphate-containing foods such as soft drinks. Phosphorus causes the body to excrete calcium. Limit or avoid high-protein animal foods. A diet high in protein causes calcium to be excreted from your body. Decrease caffeine consumption. People who smoke have significantly lower bone density, while drinking alcohol can also prevent your bones from absorbing the maximum nutrients from your food.
4. Get more Sunlight and Vitamin D
Vitamin D helps the body absorb calcium. Although some is found in oily fish, our main source comes from the effect of sunlight on your skin. It’s estimated that half of us have a deficiency because we don’t get outside enough or because we always use sunblock. It is especially important to maximize sun exposure between May and September to keep vitamin D levels topped up. Just 10 minutes of sunlight a day on bare arms and your face can cut your risk of bone fractures by a third. A half hour exposing your torso is equivalent to roughly 10,000 units of Vitamin D.
5. The right exercise
Another vital way to boost your bones is weight-bearing exercise –basically anything that has you upright and using your body weight. Good choices include squatting, rope skipping, aerobics, plyometrics, dancing or brisk walking. “Research shows that if you don’t exercise you end up weeing out all the calcium you take in instead of storing it in your bones,” warns Professor Dawn Skelton, an aging and health specialist at Glasgow Caledonian University. “Ideally we should aim for 150 minutes of moderate activity per week. “Put simply, the more hours we spend on our feet, the fewer bone breakages we should have in later life.”
6. Avoid Medications and Medical Therapies
Acid-blocking medications used for heartburn and other gastrointestinal conditions can block the absorption of calcium through the stomach walls. Stomach acids break down food during the digestive process, allowing the nutrients to become absorbed into your body. Medications designed to stop acid production or decrease the amount of acids present in your stomach can have a negative effect on calcium.