Here's why you should be adding more calcium and vitamin D to your diet—and some helpful tips to boost your intake.You probably already know most of us don't get enough calcium, but did you know more than 77 percent of the general population is also considered Vitamin D deficient? It's safe to say that many of us can stand to boost the calcium and vitamin D in our diets. After all, the two go hand in hand when it comes to optimal nutrient absorption and utilization. (Here's how to Find Out if You're Vitamin D or Calcium Deficient).
A little more vitamin D certainly can't hurt: The "sunshine vitamin" (technically, a hormone) has a significant effect on muscle weakness, pain, balance and fractures in the aging population, and research on its importance in exercise-related inflammation and prevention of chronic disease is accumulating.
All of us would benefit from an adequate intake of Vitamin D, but the exact amount of Vitamin D that's needed to boost health is up for debate. You may meet some runners who swear that their muscles function better at higher intake levels, and other runners who have never popped a supplement yet still stand on the podium.When Exercise and Supplements Don't Mix
As you can see from the table below, the recommended daily intake (per the National Institute of Medicine (IOM) and the Endocrine Society) varies widely. The IOM's recommendation is established to prevent clinical vitamin D deficiency, whereas other experts' recommendations are designed at levels much higher than 600 IU per day to help reach optimal levels of 25(OH)D (the lab marker for vitamin D).
Of course, vitamin D can be obtained when running outside in the sunshine, but the amount can vary significantly depending on the time of the year, latitude, skin pigmentation and whether you're using sunscreen, so talk to your doctor about whether or not you should take a supplement (and check out the list of Vitamin D Secrets Your Doctor Isn't Telling You). In the meantime, check out the list below to find some good food sources of vitamin D.
- Recommended Intake (IU/day): 600
- Upper Limit (IU/day): 4000
The Endocrine Society, Adults (19 to 70 years)
- Recommended Intake (IU/day): 1500-2000
- Upper Limit (IU/day): 10,000
Source: Ogan D, Pritchett K. Vitamin D and the Athlete: Risks, Recommendaitons, and Benefits. Nutrients 2013;5:1856-1868.
Good Sources of Vitamin D
A good source of vitamin D provides at least 40 IU of vitamin D per serving, which is 10 percent of the daily value for calcium (400 IU).
Portion size, standard amount: 3 ounces, smoked
Approximate Vitamin D content: (IU/serving) 580
Portion size, standard amount: 3 ounces, canned
Approximate Vitamin D content: (IU/serving) 465