Does Milk Have Vitamin D?

Milk naturally contains small amounts of vitamin D, but it's not typically found in significant enough amounts to meet daily requirements. Most milk is fortified with vitamin D to help ensure adequate intake. Fortification was introduced to help prevent rickets and support bone health, as vitamin D plays a crucial role in calcium absorption.

If you're drinking unfortified milk, it will still provide some vitamin D, but fortified milk is the more common source for meeting daily vitamin D needs.

How Much Vitamin D in Cow's Milk?

Vitamin D in milk must measure at least 100 International Units (IU) and up to a maximum of 150 IU vitamin D per eight-ounce serving per national milk standards. 

Many categories of foods are permitted to include up to a specified amount of vitamin D. The Nutrition Facts label will tell you the amount of vitamin D in the food and the ingredient list on a food label will tell you the type of vitamin D that has been added to the food.

Is Milk a Good Source of Vitamin D?

Yes! Most milk sold in the United States is fortified with enough vitamin D to be considered a “good” source, which means it provides 10% to 19% of the recommended daily intake level for Vitamin D. 

Where Does Vitamin D Come From?

Vitamin D comes from two primary sources: food and sunlight. The most commonly added form of vitamin D in milk is vitamin D3 (cholecalciferol), which is typically derived from lanolin, a substance from sheep's wool. Vitamin D3 can also be found in food sources like fatty fish (e.g., salmon, tuna, mackerel), fish liver oils and egg yolk. Vitamin D3 is also produced naturally by the skin when exposed to ultraviolet light from the sun. 

The other type of vitamin D is D2, also known as ergocalciferol, a plant source of vitamin D naturally found in mushrooms. 

Vitamin D3 vs. Vitamin D2: What's The Difference?

The main difference between vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol) lies in their sources and effectiveness. Vitamin D3 is typically derived from animal sources, while vitamin D2 comes from plants such as mushrooms. Over the years, there have been conflicting views in scientific literature as to whether D2 and D3 are equally effective at increasing and maintaining blood levels of vitamin D. 

A 2012 systematic review and metanalysis found that vitamin D3 was more effective in raising vitamin D status compared to vitamin D2, therefore could be a preferred choice for supplementation. However, more research is needed to better understand how different ways of taking Vitamin D affect the body and whether results very by age, sex, or ethnicity. 

What Is Vitamin D Good For?

Vitamin D is important, along with calcium, for keeping bones healthy. In fact, it supports and enhances the absorption of calcium. Eating vitamin D-fortified foods, like milk, orange juice and breakfast cereals (check the Nutrition Facts label), as well as natural sources like fatty fish, can help people achieve the recommended amount of vitamin D needed for good health; it's a key nutrient that helps support the immune system and can improve muscle strength.

Fluid milk in the U.S. has been fortified with vitamin D since the 1930s and has been credited with making rickets a rare disease in children, which underscores why vitamin D fortification is still relevant today. Vitamin D is an essential but often under-consumed nutrient that plays a key role in supporting good health.

Research from the National Health and Nutrition Examination Survey (NHANES) 2015–2018 shows that milk remains the top contributor of vitamin D for children in the U.S., providing roughly 31–42% of their daily intake across age and ethnic groups. For adults, milk is a key source for many populations, although intake varies by race and ethnicity. Non-Hispanic Black and non-Hispanic Asian adults often obtain more vitamin D from seafood than from milk, while children in these groups generally rely on milk as a primary source.

Many Americans may have insufficent levels of vitamin D, and vitamin D fortified milk can help meet these vitamin needs. For more information about vitamin D, check out these fact sheets for health professionals and the public.