Unless you are lying naked at midday without sunscreen on your front porch exposing your skin to bright sunlight (and to your nosey neighbors) on a daily basis, you will probably need to be taking an oral supplement to maintain your vitamin D level in the ideal range. The average American gets a paltry 150 IU daily of vitamin D from foods like tuna, salmon and fortified milk; and the typical multivitamin provides only about 400 IUs of vitamin D.
Important research from The New England Journal of Medicine found that vitamin D, when taken in higher doses- between 800 and 2000 IUs per day – substantially reduces the likelihood of broken bones in both men and women. This was a meta-analysis of 11 individual randomized controlled trials all of which focused on the effect of vitamin D supplementation in those over age 65. Among the 31,000 seniors who were taking between 800 to 2000 IU of vitamin D, they found a 30 percent decrease in the risk of hip fractures with a significant decrease in risk of fractures of other bones as well. However, the researchers found no significant reduction in fracture risk for doses of vitamin D less than 800 IUs daily.
Based on this study and a growing body of research, we recommend that you consume about 2000 IU of vitamin D3 per day. Many individuals need more than this to keep their vitamin D levels in a healthy range. Alarmingly, vitamin D deficiency is an epidemic in America, with up to 2 out of 3 Americans having suboptimal levels of this critically important compound (that is actually more of a hormone than a vitamin).
You do not need to worry that 2,000 IU will be an excessive dose. When you go outside in a bathing suit and bask in the summer sunlight, your skin will make about 10,000 IU to 20,000 IU of vitamin D per hour with no chance of creating vitamin D toxicity. Additionally, studies indicate that vitamin D supplements at concentrations of up to 10,000 IU daily seem to be safe - although we don’t recommend taking these high doses unless your vitamin D levels are being monitored. One more point: to ensure maximum absorption, try to consume your vitamin D with a meal that contains some healthy fat like olive oil, fish oil, nuts and avocados.
In Good Health,
James O'Keefe, MD and Joan O'Keefe, RD