Winter officially begins this weekend. But for some people, the lack of sunlight during winter can contribute to a Vitamin D deficiency. Here’s what you should stock up on this season. Foods such as catfish, shrimp, cod sardines and salmon are all good seafood sources of Vitamin D. Canned tuna in water is also a good source of Vitamin D, as well as whole eggs with the yolk. Mushrooms grown in ultraviolet light can contain as many as 400 international units of vitamin d in every 3 ounce portion. Dairy and non-dairy milks and orange juice are typically fortified with vitamin d, but not all. The institute of medicine recommends a daily dietary intake of 600 international units of vitamin d, or 800 international units if you’re over the age of 70.