Calcium & Vitamin D: Why Supplements Don’t Replace a Healthy Lifestyle
Posted on Apr 18, 2013 | 6 comments
For most women, especially after menopause, taking a calcium supplement with vitamin D to prevent osteoporosis is as routine as brushing your teeth. Now studies are showing that there is no proven fracture prevention at daily doses of up to 1000mg per day of calcium and 400 international units (IUs) of vitamin D. More specifically, the guidelines published by the USPSTF (U.S. Preventive Services Task Force) state the following:
- Current evidence shows no proven benefit for premenopausal women or men to take combined vitamin D and calcium to prevent fractures.
- In healthy, postmenopausal women, there is no proven benefit for taking calcium at doses of less than 400 IUs of vitamin D and less than 1,000mg of calcium.
- For healthy, postmenopausal women taking higher doses of calcium and vitamin D than the ones listed above, there is no sufficient evidence balancing risks and benefits.
Not only are studies inconclusive on the benefits of calcium, but there are also studies suggesting a possible increased risk in heart disease. This has not been confirmed by well designed studies, but an association has been observed between calcium supplementation and heart disease in men and women, presumably due to the role of calcium in the formation of artery-blocking plaques. So, healthy women taking high dose calcium supplements (more than 1,000 mg) don’t have to toss out their pills, but should be aware of the lack of proven benefits and potential risk involved. The generally recommended goal is to get a TOTAL daily calcium intake of 1000 mg per day for women up to age 50 and men up to age 70, and 1200 mg per day for older adults. Try to get most or all of this through diet since there has been no link between dietary calcium and heart disease risk.
What about Vitamin D?
Vitamin D is calcium’s best friend. It allows the calcium you consume to be absorbed and used by your body. So eating high calcium foods without adequate vitamin D stores isn’t getting you very far. Vitamin D is not just a calcium helper or your average vitamin. It’s actually classified as a hormone, like your thyroid hormone, due to its widespread effects on virtually every organ system in the body. Studies are showing that maintaining adequate vitamin D levels have benefits far beyond the bone, with potential protective effects against cancer, heart disease, and autoimmune disease to name a few.
Getting sunlight is the most natural way to trigger synthesis of vitamin D by your body and our indoor high-tech lifestyles have contributed to the epidemic of Vitamin D deficiency in adults and children. Certain ethnic groups are also at very high risk. Here in the Bay Area, severe vitamin deficiency is extremely common in both South Asian adults and children, due to darker skin pigment and prevalence of indoor high-tech occupations and lifestyles. If you suspect you might be low in vitamin D, talk to your doctor about being tested and an appropriate vitamin D dose will be recommended if your levels are low. You may need a prescription high dose form for eight weeks followed by a maintenance dose, afterwards. I recommend getting some sun and taking your vitamin D supplement if your levels are low.
Should Anyone Take Calcium and/or Vitamin D?
Individuals with osteoporosis, osteopenia (thinning of the bones), or those at high risk for osteoporosis like elderly nursing home patients, should continue taking their calcium and vitamin D. The USPTF also recommends vitamin D supplementation for seniors at risk above age 65 since studies show it lowers the risk of falls. If you’re unsure about the need for calcium and/or vitamin D, discuss with your doctor.
The Big Picture and How to Get Your Calcium
This type of story should be familiar by now. The plot goes like this. Scientific study shows particular micronutrient deficiency is harmful to health – supplement companies then feed off this news and create a product heavily marketed to public. (By the way, the supplement industry is unregulated and can make any health claims they want.) The public then flocks to purchase supplement since popping a pill is easier than making a lifestyle change.
Remember antioxidants and vitamin E? Studies showed antioxidant deficiencies were tied to virtually every disease from heart attacks to cancer to premature aging. Sounded like a great idea to just take vitamin E pills rather than get it through natural dietary sources…until they discovered that death rates went up in people taking high doses of vitamin E with absolutely no benefit ever proven at any dose.
Why don’t we give our bodies a little more credit? Your body knows when you’re trying to take a short-cut and over time it is either not going to respond or possibly produce an adverse side effect from these so-called “natural” supplements. There’s nothing “natural” about taking a bunch of artificial nutrients, cramming it into a pill, and hoping it will take care of our unnatural lifestyle habits. Vitamin D deficiency is a metabolic sign of the times…representing our addiction to being indoors, chained to our digital devices. Even kids are choosing screen time over sun time. Consider for a moment that the average American boy or girl spends just four to seven minutes in unstructured outdoor, sunlight, vitamin D-producing play each day, and more than seven hours each day in front of an electronic screen!
The ineffectiveness of calcium supplementation in most healthy women and possible risk means we need to really focus on obtaining calcium naturally through the diet. So no more “I’m not a big fan of dairy, so I’ll just take a calcium pill.” If you’re still not motivated…studies show an association between dairy intake and weight loss in women, especially when combined with optimal vitamin D levels. Healthy dairy products, leafy greens (spinach and kale), beans, and fish (especially salmon, rainbow trout, and sardines) are good natural sources of calcium. I’m not a fan of adding “calcium fortified foods” in the diet like orange juice and breakfast cereals which just add more unnecessary sugars and carbohydrates.
Get Up and Start Moving
Finally, if you’re worried about your bones, get off your chair and start moving. There is no better prescription for osteoporosis prevention than doing weight bearing exercises (walking, running, hiking, dancing, etc.). Weight bearing means on your feet so your bones and muscles work against gravity. Swimming is a great overall exercise, but not considered weight bearing, so swimmers should supplement some weight bearing exercises for additional bone protection.
Remember, no amount of calcium or vitamin D supplementation can ever compare to good nutrition, exercise, and getting healthy doses of sunlight.
This blog post is contributed by Ronesh (Ron) Sinha, M.D., Palo Alto Medical Foundation Internal Medicine. Dr. Sinha works closely with the South Asian community to help reduce heart disease and diabetes risk, and provides corporate health lectures to promote wellness in the workplace. Dr. Sinha holds clinical faculty positions at UCLA; Stanford University School of Medicine; and the UCSF School of Medicine. He teaches Stanford and UCSF medical students.