Vitamin D helps the body absorb calcium and maintain healthy bones. It also supports normal muscle function and plays a role in the immune system. For vegetarians, obtaining enough of the nutrient requires attention to food choices because many natural dietary sources, including oily fish, are excluded.
The options available depend partly on the type of vegetarian diet a person follows. Eggs and dairy products can contribute vitamin D for those who eat them, while fortified foods and certain mushrooms are important alternatives for people who avoid animal products.
Mushrooms can provide vitamin D
Mushrooms are among the few non-animal foods that naturally contain vitamin D. Their vitamin D content depends partly on exposure to ultraviolet (UV) light, which can increase the amount of the nutrient they produce.
Mushrooms grown indoors without UV exposure may contain relatively little vitamin D, while UV-treated varieties can provide substantially more. The amount varies by variety and growing conditions, so consumers should check product information where available.
Mushrooms also contain other nutrients, but their vitamin D content should not be assumed to be high simply because they are included in a vegetarian diet.
Eggs offer smaller amounts
For vegetarians who eat eggs, egg yolks provide another dietary source of vitamin D. The amount varies depending on factors including the hen’s diet.
Eggs also supply protein and other nutrients, but they contain much less vitamin D than oily fish. They are therefore best considered one contributor to overall intake rather than a reliable source on their own.
Fortified foods are important for vegans
People who avoid eggs and dairy products have fewer naturally occurring dietary sources of vitamin D. Fortified foods can help fill that gap.
Some brands of soy, oat, almond and rice drinks contain added vitamin D. Certain breakfast cereals, spreads and orange juice products are also fortified, although availability and nutrient levels differ between brands and countries.
Consumers should check food labels to confirm whether vitamin D has been added and how much a serving provides. Products labelled as plant-based are not necessarily fortified.
For vegans, it is also important to check the source of added vitamin D. Vitamin D3 is sometimes produced from lanolin, a substance obtained from sheep’s wool, while vitamin D2 is derived from fungi or yeast. Some products use alternatives suitable for vegans.
Dairy products and supplements
Milk, cheese and other dairy products may contribute vitamin D, but their content depends on whether they have been fortified. In countries where fortification is uncommon, dairy products may provide relatively little of the nutrient.
Butter should not be relied on as a major source of vitamin D. Nor is replacing fish with tofu an equivalent nutritional substitution: ordinary tofu is not necessarily rich in vitamin D unless it has been fortified.
Diet is only one part of maintaining adequate vitamin D levels. The body also produces vitamin D when skin is exposed to sunlight, although production varies with skin pigmentation, age, location, season and other factors.
The US National Institutes of Health says the recommended daily intake is 15 micrograms (600 international units) for people aged 14 to 70, including teenagers aged 14 to 18. The recommendation rises to 20 micrograms (800 IU) for adults over 70. Individual needs can differ.
People who have limited sun exposure or few dietary sources may need advice from a healthcare professional about supplementation. Taking high doses without medical guidance can be harmful, and supplements should not automatically be assumed necessary for everyone who follows a vegetarian diet.
For vegetarians, the practical approach is to combine suitable foods, check fortification labels and consider individual circumstances when assessing vitamin D intake. A varied diet can help, but food alone does not always provide enough of the nutrient.

