We all know that whole milk contains vitamin D. Every visit to the grocery store reinforces this fact. Containers of whole milk are emblazoned with “Vitamin D Milk” on the label. The association is so strong that many people refer to whole milk as “vitamin D milk”.

But something important gets lost in translation: The fact that other varieties of cow’s milk sold in grocery stores also contain vitamin D.

This bears repeating because it’s a little-known fact: Whole, reduced-fat (2%), low-fat (1/2% and 1%) and fat-free (skim) milk all contain the same amount of vitamins and minerals, including vitamin D. The only difference: The amount of fat, and therefore, the amount of calories.

Cow’s milk is fortified at the standardized level of 400 IUs (International Units) of vitamin D per quart. That means each cup of milk (8 oz.) contains 100 IUs of vitamin D.

Let’s put the level of 100 IUs of vitamin D per serving in perspective: The current recommendation for vitamin D intake for adults is 200-400 IUs per day (depending on age) according to The Institute of Medicine, however, many nutrition experts believe adults should get 1,000-2,000 IUs of vitamin D per day for overall health and to help prevent chronic disease.

My point is that milk is a good source of vitamin D—in fact it’s the largest single food source of vitamin D in the U.S. according to an analysis of data from a national health and nutrition survey (NHANES, 1999-2002). But it’s highly probable that we need even more vitamin D than we obtain by eating a well-balanced diet, even a diet that consistently includes vitamin D-rich foods such as salmon, tuna, eggs, fortified dairy foods and fortified cereals.

Stay tuned while researchers conduct additional studies on vitamin D and health and release new dietary intake recommendations in 2011. Since vitamin D can be manufactured in the skin with exposure to sunlight, prudent sun exposure may be a part of the expert’s recommendations.

Vitamin D was discovered around 1920. Researchers knew that there was a nutritional factor in cod liver oil that cured rickets (bone softening and malformations in children) but their research indicated it wasn’t vitamin A, and since vitamins B and C had already been discovered, they dubbed the rickets-curing factor “vitamin D”.

In 1932, milk was chosen as the delivery vehicle for vitamin D because milk was widely consumed by children at the time. Vitamin D fortification of milk was endorsed in 1933 by the American Medical Association Council on Foods and Nutrition.

Although milk processing plants aren’t required to fortify milk with vitamin D, the vast majority do so to help protect public health. Ninety-eight percent of milk sold at retail is fortified with vitamin D.

To ensure that the level of vitamin D fortification in milk meets specifications, milk is routinely tested for its vitamin D content. Milk monitoring is conducted primarily by state governments in cooperation with the Food and Drug Administration (FDA). The acceptable range allowed for vitamin D fortification of milk is not less than 100% and not more than 150% of label claims (i.e. 400-600 I.U. vitamin D per quart is acceptable).

In Michigan, it’s estimated that 98 percent of adults are vitamin D deficient. In the U.S., it’s estimated that 9 percent of children and teens are vitamin D deficient and 61 percent are vitamin D insufficient.

Include plenty of vitamin D-rich foods in your diet and discuss aspects of vitamin D and health with your doctor or dietitian, including diet, sun exposure and the possible need for vitamin D supplements.

Get the D You Need From:

• A little sun. Sensible sun exposure is one source. Some experts suggest 15 minutes in the sun at least three times a week; then apply sunscreen and/or cover up.
• A variety of vitamin D-rich foods. Include vitamin D-rich foods in a well-balanced diet. Check the Nutrition Facts panel on the food label for vitamin D content.
• A vitamin D supplement. Chances are, you’ll also need a supplement. The latest research indicates most adults need 1,000-2,000 IUs of vitamin D daily.

Food Sources of Vitamin D (IUs):
For packaged food, check the label for vitamin D content since it may vary depending on the brand.
Cod liver oil, 1 Tbsp: 1,360*
Salmon, wild, 3.5 oz: 988
Salmon, farm-raised, 3.5 oz: 245-360
Sardines, canned in oil, drained, 1.75 oz: 250
Tuna, canned in oil, 3 oz: 200
Mackarel, 3.5 oz: 24-345
Milk (vitamin D fortified fat-free, low-fat, reduced-fat and whole), 1 cup: 100
Yogurt (vitamin D fortified), 6 oz: 40
Cereal (vitamin D fortified), 1 cup: 40
Orange juice (vitamin D fortified), 6 oz: 38
Kraft Singles cheese product (vitamin D fortified), 1 slice: 34
Margarine (vitamin D fortified), 1 tsp: 20
Egg, 1: 20

*Go easy on the cod liver oil because it’s also very high in vitamin A.

More:

Milk’s Unique Nutrient Package:
http://www.nationaldairycouncil.org/SiteCollectionDocuments/health_wellness/dairy_nutrients/MILKsUniqueNutrientPackage.pdf

Vitamin D and Health:  http://www.vitamindhealth.org/

Office of Dietary Supplements, National Institutes of Health: http://ods.od.nih.gov/factsheets/vitamind.asp

Research review: “A New Appreciation of Vitamin D,” Dairy Council Digest, March/April 2007. http://www.nationaldairycouncil.org/SiteCollectionDocuments/research/dairy_council_digests/2007/dcd782.pdf

Karen