I’ve made the argument before that some supplements may be necessary to prevent a nutrient deficiency even if you’re nourishing your body with a nutrient-dense, whole-foods diet. Some nutrients are challenging to get through food alone, especially if you’re not digesting food optimally or you’re struggling with a chronic disease that increases your need for particular nutrients. I recommend wise supplementation for many of my patients, and I have seen the benefits of supplementation in my own life as well.
That said, there are several supplements that are commonly recommended by conventional doctors and healthcare practitioners that are unneeded at best, and potentially harmful at worst. Calcium supplements are a prime example of this.
Do Calcium Supplements Work?
Calcium has become extremely popular to supplement with, especially among aging women, in the hope that it will prevent fractures and protect against osteoporosis.
We’ve all seen the products on the market aimed at the “worried well,” such as Viactiv and Caltrate, suggesting that supplementing with calcium can help maintain bone health and prevent osteoporosis. Osteoporosis is a serious concern in women’s health, and it affects at least 10 percent of American women. (1) Yet the evidence that calcium supplementation strengthens the bones and teeth was never strong to begin with, and it has grown weaker with new research published in the past few years.
Are you taking a common supplement that may increase the risk of heart disease, stroke, and death? Read this article to find out.
A 2012 analysis found that consuming a high intake of calcium beyond recommended dietary guidelines, typically from supplementation, provided no benefit for hip or lumbar vertebral bone mineral density in older adults. (2) A 2007 study published in The American Journal of Clinical Nutrition found that calcium supplements don’t reduce fracture rates in postmenopausal women and may even increase the rate of hip fractures. (3)
Are Calcium Supplements Safe?
Beyond being ineffective for bone health, calcium supplements are associated with some pretty serious health risks.
Heart Disease Risk
Studies on the relationship between calcium and cardiovascular disease (CVD) suggest that dietary intake of calcium protects against heart disease, but supplemental calcium may increase the risk. A 2012 study of 24,000 men and women aged 35 to 64 years published in the British Medical Journal (BMJ) found that those who used calcium supplements had a 139 percent greater risk of heart attack during the 11-year study period, while intake of food calcium did not increase the risk. (4) A meta-analysis of studies involving more than 12,000 people also published in the BMJ found that calcium supplementation increases the risk of:
- Heart attack by 31 percent
- Stroke by 20 percent
- Death from all causes by 9 percent (5)
An analysis involving 12,000 men published in JAMA Internal Medicine found that intakes of over 1,000 mg of supplemental calcium per day—from multivitamins or individual supplements—were associated with a 20 percent increase in the risk of death from CVD. (6) Researchers suspect that the increase of calcium in the blood that occurs after supplementation may facilitate the calcification of arteries, whereas calcium obtained from food is absorbed at slower rates and in smaller quantities than from supplements. (7) It is also suspected that extra calcium intake above one’s requirements is not absorbed by the bones, but is excreted in the urine, increasing the risk of calcium kidney stones. The excess calcium could also be circulated in the blood, where it might attach to atherosclerotic plaques in arteries or heart valves. (8)
Cancer, Kidney Stones, and Other Health Risks
The Office of Dietary Supplements at the National Institutes of Health has compiled a comprehensive review of the health risks associated with excess calcium, particularly from supplementation. (9)
For example, daily supplementation of calcium at 1,000 mg is associated with increased prostate cancer risk and an increase in kidney stones. (10)
Additionally, a recent Swedish study reported a 40 percent higher risk of death among women with high calcium intakes (1,400 mg and above), and a 157 percent higher risk of death if those women were taking a 500-mg calcium supplement daily. Those rates were compared to women with moderate daily calcium intakes between 600 and 1,000 mg. (11) A Consumer Lab analysis found that many of the calcium supplements they analyzed failed quality testing for reasons including lead contamination and mislabeled contents. (12)
Other Forms of Calcium Supplementation
Even if you’re not popping a calcium pill every morning, that doesn’t mean you’re not consuming supplemental calcium. Many commonly consumed foods in the United States are fortified with supplemental forms of calcium, including:
- Orange juice
- Breakfast cereals
- Non-dairy milk
- Instant oatmeal
- Graham crackers
- Other staples of the Standard American Diet
While these foods are typically eliminated on a whole-foods or Paleo diet, it’s important to pay attention to whether some of your fridge staples, such as commercial almond, coconut, or other varieties of non-dairy milk, are fortified with calcium. You may be consuming more supplemental calcium than you realize.
In addition, many multivitamins contain significant amounts of calcium, so be sure to check the label if you’re taking one. This is one reason I advise you to throw away your multivitamins in most cases: they contain too little of the right nutrients and too much of the wrong ones.
The Safest Ways to Get Enough Calcium
If you’re concerned about keeping your bones healthy, you’re better off getting your calcium from food sources like:
- Dairy products
- Canned, bone-in fish (e.g., sardines, salmon, etc.)
- Dark, leafy greens
- Seeds (especially poppy and sesame)
The Recommended Dietary Allowance (RDA) for calcium for adult men and women is 1,000 mg—or approximately three servings of dairy products or bone-in fish per day. Pregnant and lactating women, and adults 70 and older, need 1,200 mg per day.
If you’re not able to meet your daily needs for calcium with diet alone, there is one calcium supplement that is unlikely to cause the problems that are associated with most other forms of supplemental calcium: whole bone calcium.
Whole bone calcium is a natural, bone-derived calcium complex that contains not only calcium, but also collagen, growth factors, trace minerals, and all of the other elements that are present in healthy bone tissue. It would be expected to affect the body more like dietary calcium than like a calcium supplement, and for this reason I think it’s a good option for those that can’t get enough calcium from the diet.
Unfortunately, it’s difficult to find whole bone calcium supplements in local stores. I recommend Free-Range Pasture-Fed Whole Bone Calcium from Traditional Foods Market online to my patients. It’s made from free-range, pasture-fed cows from New Zealand.
Healthy bone formation also depends on vitamin D and vitamin K2, both of which regulate calcium metabolism. There are also other minerals besides calcium involved in supporting bone health, such as silica and magnesium. If you have adequate levels of these nutrients and regularly perform weight-bearing exercise, there is no need for calcium supplementation, which will likely do more harm than good. (13)