As a result of a broken shoulder from a fall this past summer, I have been on a regime of one vitamin D3 and two 600 milligrams calcium pills daily. Recently in The Journal Gazette an item stated a government panels finding disputed the value of vitamin D and calcium pills. There is doubt these pills actually offer bone protection. A good diet that includes fruit, fruit juice, dairy products, fish, fortified milk and cereals is more than sufficient in providing vitamin D and calcium. Should I continue or abandon the taking of these pills?
There has been much confusion surrounding the topic of vitamin D doses and whether supplementing natures sunshine vitamin is a good idea or not. The study that you are referencing was published by the U.S. Preventive Services Task Force and specifically referenced that there is insufficient evidence that taking 400 international units of vitamin D daily as part of a combined calcium supplement reduced the risk of bone fractures. Interestingly, the same paper stated that higher doses of vitamin D showed a reduction in the fracture risk.
The Institute of Medicine recently published its thoughts regarding vitamin D dosing and bone protection. Their recommendations are a daily intake of 600 international units (iu) for adults under 70, and 800 iu if you are older than 70 or have other medical risk factors with 4,000 iu being the upper tolerable limit for daily dosing. It is important to note that this represents a significant increase from previous recommendations of 200 iu daily dose and 2,000 iu upper limit. They also stated that their review of the literature focused on the bone protective benefits of vitamin D, and though questions regarding the cardiovascular, immune system and cancer fighting effects of vitamin D were of interest, further research would be necessary before dosing recommendations could be made in these areas.
Vitamin D is manufactured by the skin in response to sun exposure and is converted by the kidneys to its more active form. As we age, we become less efficient at manufacturing vitamin D. Also, persons with darker skin tones make less vitamin D. Fortified foods have vitamin D2 known as ergocalciferol. This is a less effective form than targeted supplements containing vitamin D3, or cholecalciferol. Obesity is another risk factor for vitamin D deficiency, as is the widespread use of sunscreens, working indoors and living in a northern climate. We are also finding that people have genetic differences in the effectiveness of their vitamin D receptors. This may mean that despite eating whole foods high in calcium such as fish, eggs, mushrooms and others, we may still have low vitamin D levels.
Excess vitamin D and elevated calcium can occur with prolonged use of high-dose supplements and can result in muscle aches or kidney stones. Elevation of calcium levels has been implicated in some forms of heart disease, though research has also suggested that heart issues may be associated with low calcium levels as well.
When deciding whether or not to supplement vitamin D, calcium, or any other substance, it is important to talk with your doctor. He or she can check a blood level to look for deficiency, monitor your dosing and help you with a comprehensive plan to improve your bone health that includes the right supplements, nutrition and exercise with balance training to prevent further injury and protect your health.