Common Vegan Diet Nutrition Deficiencies

Wondering if you have a vegan diet nutrition deficiency? Find out about the most common ones and what you can to to spot and prevent them.

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If you’ve ever looked at the nutrition label on a jar of multivitamins, you know just how many nutrients are packed into those tiny capsules (or gummies!).

But since you need so many vitamins and minerals to keep us strong and healthy, how are you supposed to know if and when you need to up your intake of any particular one? And is food first the way to go?

For plant-based eaters, knowing about the most common vegan diet nutrition deficiencies is very important.

The good news: You don’t need to have a blood test every few months to clue you in on if you’re nutrient deficient. Your body is actually pretty darn good at alerting you by showing various signs.

The tricky part? Many of the symptoms of nutritional deficiencies may seem normal to you if your body has been running on lower fuel for awhile.

Get all the info you’re seeking about how to prevent a vegan diet nutrition deficiency.

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Vitamin D deficiency

Here’s a common vegan diet nutrition deficiency. Before I started eating seafood, it was difficult for me to get enough vitamin D through food—since the main dietary sources are fatty fish like salmon, tuna, and mackerel. Now, I eat seafood several times a week.

Why it’s common

Other foods like dairy products (including cheese, fortified milk, and yogurt) and milk contain small amounts, but when I was a vegetarian I would have to strategically plan what I would eat every day to get enough.

Of course, you can take in vitamin D through the sun to prevent a vegan diet nutrition deficiency, but it’s hard to absorb enough while also protecting your skin.

Vitamin D is important for keeping your bones strong—it helps you absorb calcium and keeps your body’s stores of this and other important bone minerals in check.

And studies show it may also help boost your immunity. If you’re wondering about vitamin D and weight control, science linking the two is very early and not yet proven.

I’ve had my vitamin D level tested several times through blood work to see if I was deficient in the vitamin.

The results have always landed me in a healthy range—but to ensure they stay there, I make sure I eat vitamin-D-rich foods. And when I was a vegetarian, I took a daily supplement.

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How to prevent a deficiency

Researchers say the best way to absorb a vitamin D supplement is to take it with a meal containing fat, per a study in the Journal of the Academy of Nutrition and Dietetics.

When volunteers in the United States paired a vitamin D supplement with a meal that had 30 percent of total calories as fat (so about 120 calories, or 13 grams of fat, for a 400-calorie meal), they absorbed the vitamin D 32 percent better, versus folks eating a meal without fat.

If you decide to get tested and come up deficient, your doctor may prescribe a high-dose supplement. But if you land in a healthy range or aren’t sure if you already get enough, pick a supplement with less than 1,000 IU vitamin D.

You can choose a capsule or try a liquid formula, which makes it very easy to control the dose. Most women and men need to take in 600 IU daily—or 800 IU if you’re older than 70.

There are actually two types of vitamin D. Yup! However, vitamin D3, which is absorbed more efficiently by the body than vitamin D2, is typically animal based. Thus, most vitamin D3 supplements are not vegan.

Because vitamin D is a fat-soluble vitamin, it makes sense that a meal containing fat would enhance its absorption—although this is some of the first research to prove this.

One caveat of the study: While scientists tested a supplement containing 50,000 IU vitamin D, a typical dose would contain much less than that.

So it’s possible that a fat-containing meal affects the absorption of a smaller amount differently than found in the study findings. Now, forge forth to prevent a vegan diet nutrition deficiency!

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Vitamin B12 deficiency

This is another common vegan diet nutrition deficiency. B vitamins help with energy regulation—which is why if you’re deficient in vitamin B12 you may notice a decrease in energy.

Why it’s common

Many vegans and vegetarians don’t take in enough vitamin B12. This is because many sources are animal based.

If you don’t take in enough, this can harm your health, as vitamin B12 is important for necessary body functions—including production of red blood cells and proper maintenance of the central nervous system.

How to prevent a deficiency

If you’re a vegan eater, you may need to take a vitamin B12 supplement to prevent a vegan diet nutrition deficiency.

Also, after age 50 or so, your body may have a more difficult time absorbing vitamin B12 from food sources.

The reason? After this age, the stomach secretes less hydrochloric acid after this age, and this is what’s responsible for helping your body separate vitamin B12 from protein in the foods you eat.

So if you haven’t been taking a supplement before, you may want to consider taking one if you are in this age range

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Omega-3 deficiency

Here’s one more common vegan diet nutrition deficiency.

Long before I was a pescatarian, I took omega-3 supplements on the daily. Why? Because EPA and DHA omega-3 fatty acids, found in fatty fish, are super beneficial food to your health. 

Why it’s common

These nutrients help your heart health, brain health, and more. Because vegan eaters aren’t eating the recommended least two 3.5-ounce weekly servings of cooked fatty fish weekly, I’d recommend you take a daily supplement.

It’s important to note the difference between EPA, DHA, and ALA omega-3s. ALAs are short-chain omega-3s found in certain plant foods like flaxseeds.

To prevent a vegan diet nutrition deficiency, it’s essential to get enough DHA and EPA omega-3s.

It’s important to get your fill of ALA, but only a small amount of ALA converts to EPA and DHA. That’s why it’s so important to take in enough of these long-chain omega-3s, which are found in fatty fish and certain algae—as well as a handful of fortified foods.

How to prevent a deficiency

As a vegan eater, you can take omega-3 supplements that source EPA and DHA from a specific type of algae. This is the same algae that fish eat to form omega-3s.

Additionally, omega-3s are very important for a healthy plant-based pregnancy.

Final thoughts

There are many vegan diet nutrition deficiencies, as several nutrients come from animal-based products such as eggs, meat, and fish. Because of this, you may want to consider taking certain supplements.


Wondering if you have a vegan diet nutrition deficiency? Find out about the most common ones and what you can to to spot and prevent them.

I’d love to hear from you! Are you worried about having a vegan diet nutrition deficiency?

Plant-Based Eating | Supplements |

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