Foods High in Vitamin D: Boost Your Immune System

Fun in the sun, fish and milk all serve as good sources of vitamin D. Not your cup of tea? A supplement may be the answer.

Vitamin D is a funny thing. Our bodies make it naturally after sun exposure, and you can get it through your diet as well. But this is only an appropriate resource if you’re up for eating a few very specific foods high in vitamin D. Otherwise, it’s far from natural, the result of government-instituted fortification programs.

First, let’s take a moment to consider the important role that Vitamin D plays in the body. It is a fat-soluble vitamin that aids cell growth and immune function, and it helps to reduce inflammation.

The more we learn about nutrition and medicine, the more scientists are beginning to understand the role that inflammation plays in the body, and its connections to various chronic diseases. Vitamin D also promotes calcium absorption in the body, and the two actually work together to promote bone health.

Though vitamin D deficiency has become relatively rare today, it does still occur. It is most common among older individuals who are no longer able to synthesize vitamin D from sunlight efficiently, individuals who do not get significant amounts of daily sun exposure, and lactose intolerant or vegan/vegetarian individuals who do not consume significant quantities of vitamin D in their diets.

According to the National Institutes of Health, significant quantities of vitamin D are actually naturally available in very few foods. Others are fortified with vitamin D during production, to address the public need for adequate vitamin intake.

Fun in the sun

woman sleep on green grass

Daily sun exposure remains the best way to get on track with healthy levels of vitamin D. UV rays initiate a response of vitamin D synthesis in the body, which is then further modulated by the liver and the kidneys. Many doctors actually recommend about fifteen minutes of unprotected sun exposure per day in order to assure that we are producing adequate amounts. This can be a problem in extreme northerly regions, where the sun sits below the horizon more often than not.

This is in no way an encouragement to ditch the sunscreen, since the risk of cancer induced by sun damage remains a cause for concern. It is, however, a reminder to get in some time outdoors in the sunshine whenever you can.

At least where vitamin D is concerned, a bit of daily physical activity contributes more to health if you’re simultaneously able to soak up some rays. Though adequate sun exposure is probably the best way to be sure you’re getting enough of this vitamin, you can get it through your diet as well.

Eat more fatty fish

Raw salmon fish steaks with fresh herbs on cutting board

Fatty fish offer the highest amounts of naturally-occurring vitamin D per serving. Though nutritional experts discourage daily consumption of large fish like swordfish and tuna, (due to their high and potentially detrimental mercury levels, especially for pregnant women and young children) smaller fish remain a boon to health. Not only are salmon and sardines packed with healthy omega-3s (great for brain health!), they serve as a good source of vitamin D as well.

A 3-oz serving of salmon provides more than the daily requirement of 400 IUs of vitamin D for the average adult. But pay attention to those portions—3 ounces of tuna canned in water provides only 153 IUs, and two sardines from a can (the quantity presumed to be a serving) contain only 46 IUs of vitamin D.

An argument for animal products

Though fatty fish is officially the best source, other animal products aren’t far behind in terms of vitamin D content. If you’ve had enough of fish for the week, look to other animal-derived sources. These include beef liver, egg yolks and cheese. Though liver has mostly gone out of style for the average diner, it bears repeating that organ meats are a rich, readily available source of many vitamins and minerals. Sadly, they are often wasted since demand is low.

Talk to your butcher, or perhaps your grandmother—they’ll know what to do with that liver! Who knows- maybe it will even show up on your favorite restaurant menu some time soon.

Due to the high levels of cholesterol that they contain, Americans are discouraged from gorging on eggs and cheese. And gorge is what you would have to do, if your aim is to significantly increase your vitamin D intake. One large egg contains only 41 IUs of vitamin D, and you would be hard-pressed to find a nutritionist out there who is ready to advocate for a diet that includes a minimum of nine or ten eggs per day.

Though other food sources (like turkey, Canadian bacon and pork ribs) contain vitamin D, the amount of any one of these foods that you would have to consume in a day to maintain adequate levels of vitamin D, would be unhealthy at best (due to high levels of salt and fat, not to mention calories) and dangerous at worst (again, due to negative impacts on health).

Are mushrooms the answer?


The good news for vegetarians is that another food source for naturally-derived vitamin D is out there. Though it’s often buried in the literature, mushrooms are in fact a viable option. This, of course, depends on which mushrooms you’re eating, and in what quantities. Preparation also comes into play.

Mushrooms can be hard to digest and they actually contain small amounts of toxins, which some experts believe to be potentially carcinogenic. There’s a simple solution to both of these problems- cook your mushrooms before you eat them! But what about the nutrients?

Maitake mushrooms contain a whopping 786 IUs of vitamin D per cup, but only if they’re served raw. Portobello mushrooms that have been exposed to UV light (to boost their vitamin D levels before they are harvested) are available, and the higher levels of vitamin D are still found intact after the mushrooms have been grilled. Unfortunately, these naturally fortified types of mushrooms can be difficult to find.

Cooking causes vitamin degradation in all kinds of foods, including the aforementioned fish (which serves as a much better source of vitamin D when consumed raw or smoked, rather than grilled or otherwise cooked). Cooked mushrooms still contain vitamin D, but far less than their raw counterparts. For example, stir-fried shiitake mushrooms contain about 19 IUs of vitamin D per cup.

White mushrooms (the most common variety outside of Asia, like the type that you would typically find on your slice of pizza) contain only 12 IUs of vitamin D per cup if boiled, and even less if they’ve been stir-fried instead.

If you’re weighing your options between a possible tummy ache and eventual cancer (the ultimate potential negative side effect) as a result of eating your mushrooms raw, versus low vitamin D levels if you decide to cook them instead, the choice should not be that difficult. I’m going to take this opportunity to suggest that you stick to a varied, healthy diet instead, with possible vitamin supplementation as necessary.

Food should be delicious, and a diet that will make you both happy and healthy should always be within reach. I did not even mention the high vitamin D content found in cod liver oil here, because I know how unpalatable it can be. If you are forced to hold your nose while “eating” or if your food is causing you digestive upset, you are eating the wrong foods. Vitamin content be damned.

Don’t give up (making an official admission of defeat, or a declaration that all food sources of vitamin D are unavailable to you since you perceive them as unpalatable, or downright disgusting)! Instead, do whatever you can to maintain a healthy, varied diet that tastes good. True, this may take some effort, and possibly even a bit of trial and error. But this will be worth it in the long run.


Though naturally-derived nutrients are the most bioavailable, and thus optimal for health, we do live in a world where nutrients are added to our foods. Just as folic acid is now routinely added to breakfast cereal in a largely successful effort to combat the occurrence of certain birth defects, other vitamins and minerals are routinely added to foods in the US and around the world by major manufacturers.

Salt is iodized, water is fluoridated, and calcium is added to orange juice. Vitamin D is also added to that orange juice since, as was stated above, it aids calcium absorption in the body. Just a little digging online quickly reveals that vitamin D is added to other foods as well.

Milk and breakfast cereal are the most common foods fortified with vitamin D in the US. Milk was originally fortified back in the 1930s in an effort to combat rickets, a significant public health concern at the time. Though this is a problem that we rarely hear about today, the government continues to mandate fortification of these foods.

Fortified orange juice, as has been mentioned already, as well as yogurt, margarine and other fortified products are widely available. Baby formula is fortified with vitamin D, as are various types of cheese. But these foods are often high in fat, sugar and salt as well. Weigh your options carefully, and perhaps consider the final item on this list as an alternative…


Cod liver oil gel capsules

If you’re a vegetarian, vegan, or you just hate to drink your milk, perhaps a supplement is for you. To me, this is an item of last resort. Sure, I’ll pop a multivitamin once in awhile, if I’m feeling run down or if I know that I ate poorly while I was on vacation. But in general, I prefer to get my vitamins and nutrients from food sources, and the experts agree.

Many (if not most) nutritionists discourage individuals from taking vitamin supplements in favor of a healthy, balanced diet, but natural food sources of vitamin D are scarce. If meat and the sun are both your enemies, you may want to consult with your doctor or licensed physician to be sure the old vitamin D levels are within normal range.

Though vitamin supplements result most frequently in nothing more than expensive pee (the byproduct of flushing the body of excess vitamins and minerals) this can be a good solution for those who really need it.

If you’re a vegetarian or you’re lactose intolerant, maybe you want to remind yourself to throw that “orange juice + D” in the cart the next time you’re at the grocery store. Keep eating a varied diet, and continue to exercise at least a few times per week. Ditch the parasol the next time you’re out walking the dog. And put your wallet away- save the cash that you would have spent on vitamin supplements, at least until you’ve consulted with a doctor to find out whether you really need them.

About the author

Allison M. Sidhu

With a master’s degree in gastronomy, this girl’s got food on the brain! Allison’s a Philly native and recent transplant to LA. When she’s not exploring the local food scene, she loves snacking on homemade goodies in front of the TV with her husband.

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