Vitamin D is important for maintaining strong bones and a healthy immune system. Some studies suggest it may also help reduce diseases like diabetes and cancer, though more research is needed.  

Vitamin D sources include:

  • Fatty fish – salmon, halibut, tuna, trout, mackerel, sardines
  • Fortified products – orange juice, cereals and many dairy products
  • Eggs

600 IU of vitamin D is recommended for most adults and some studies suggest getting 1000 IU or more may have benefits.

It can be hard to get enough vitamin D through diet alone. Eating a tuna sandwich, egg, and cup of milk only provides about half the daily amount. Read food labels (hint: a daily value of 20% or more is an excellent source) or take a supplement to meet your needs during the winter.

This article originally appeared on, an employee wellness program sponsored by MGH Nutrition and Food Services.