10 Causes of Fatigue in Vegans

More and more people are choosing to eat vegan, a lifestyle that focuses on avoiding all animal products.

While a plant-based (vegan) diet can offer health benefits (as long as it consists of unprocessed products), some vegans also experience fatigue at times.

This is often the result of deficiencies of important nutrients.

In this article, I'll explain which nutrients vegans often lack. You'll also learn what you can do to prevent fatigue in vegans.

There are several nutrients that are difficult for vegans to get enough of. These deficiencies can lead to a lack of energy.

It's important to understand why you, as a vegan, are at risk for these deficiencies and how they can leave you feeling fatigued.

These are common causes of fatigue in vegans:

Iron is also essential for good energy. Although vegans often get more iron than vegetarians and meat eaters, many vegans are still deficient.

This is because heme iron, which is found in animal products, is better absorbed by the body (15-35%) than non-heme iron, which is found in plant sources (on average 5-12%).

Supporting Study - Although vegans on average consume more iron (21.0 mg/d) than vegetarians (15.3 mg/d) and meat eaters (13.9 mg/d), studies show that iron absorption from plant sources is significantly lower. This is due to the lower bioavailability of non-heme iron.(1)(2)

A protein deficiency can lead to fatigue because your body doesn't have enough building blocks for muscle repair and energy production.

Many vegans often fail to meet their daily protein needs. This is because plant proteins are often "incomplete," meaning they lack some essential amino acids and are less well absorbed.

Furthermore, your body processes proteins less efficiently if your diet contains antinutrients like phytates. These substances are common in the plant-based products that vegans often eat.

Supporting Study : A study based on 26 studies with nearly 10,000 participants shows that 27% of vegans do not consume enough protein. This is especially concerning for essential amino acids like tyrosine and lysine, which the body cannot produce on its own.(3)

Vegans are at increased risk of deficiency because vitamin D is mainly found in

Found in animal products. If you don't get enough vitamin D, you may notice symptoms such as muscle soreness and fatigue.

Sunlight is also an important source, because your body can convert sunlight into vitamin D in your skin. The risk of a deficiency is therefore greater in the winter than in the summer months. 

Supporting Study - Research shows that average vitamin D intake is highest in pesco-vegetarians (5.25 µg/d), followed by meat eaters (4.17 µg/d), vegetarians (2.67 µg/d) and lowest in vegans (1.52 µg/d).(1)

As a vegan, you are also more likely to have a zinc deficiency, which can lead to fatigue, because zinc supports energy production and cell protection.

This deficiency often occurs because vegans do not consume animal products, which are rich in zinc.

In addition, plant foods (such as legumes, grains, and nuts) contain phytates, which reduce zinc absorption.

Supporting study - Studies show that average zinc intake in vegans is significantly below the recommended daily allowance, especially for men. About 30% of vegans are zinc deficient.(1)(2)

We need calcium for strong bones and teeth, but it's also important for your energy metabolism. Furthermore, calcium is good for your muscles and nerves.

A calcium deficiency can therefore be a cause of feeling tired.

Vegans often have an increased risk of calcium deficiency because they do not consume dairy products, which are an important source of calcium.

Fortunately, calcium is also found in many plant foods, such as tofu, dark green vegetables, beans, sesame seeds, figs, and almonds.

Supporting Study - A meta-analysis of 74 studies found that vegans have significantly lower calcium intakes than vegetarians and omnivores. This highlights the importance for vegans to monitor their calcium status closely to prevent deficiencies.(5)

Too little omega-3 fatty acids in your diet can also cause fatigue, as these fatty acids contribute to your brain function and energy management.

Vegans are more likely to have an omega-3 fatty acid deficiency because they don't eat fish or marine products rich in the important fatty acids EPA and DHA.

Plant-based omega-3, such as in linseed, is less effective because our body has more difficulty converting it into the required forms.

Supporting study - Research shows that vegans often have lower levels of omega-3 fatty acids like EPA and DHA. Although they consume alpha-linolenic acid (ALA) from plant sources, its conversion to EPA and DHA is limited. Algal oil may be an effective way to increase these levels. (6)(7)

Iodine is essential for the production of thyroid hormones, which directly affect your energy levels.

Because most plant foods are low in iodine, many vegans are deficient, which can be a cause of fatigue in vegans.

Supporting Study - Studies show that vegans have significantly lower iodine intake compared to non-vegans, with as many as 92% of them being iodine deficient.(1)

There are more and more vegan products on sale that are highly processed and therefore often contain few valuable nutrients.

This puts you at risk of deficiencies in essential vitamins and minerals, which can lead to fatigue.

In addition, plant-based diets are often naturally lower in calories, as they typically contain less fat and more fiber. This can help you feel full faster, leading to fewer calories consumed.

It's important to consume enough calories because a healthy vegan diet is very bulky. Eating too little can lead to fatigue, hunger, and irritability.

By paying attention to your diet and planning your meals well, you as a vegan can prevent deficiencies, and therefore fatigue.

These tips will help you get enough essential nutrients, which will make you feel fitter and more energetic:

A B12 deficiency can develop slowly, meaning symptoms may not become apparent for months or years. Therefore, have your B12 levels tested regularly and take supplements containing the active form of B12, such as methylcobalamin .

The most commonly used test measures total B12 levels, but it may also be useful to do the methylmalonic acid (MMA) test, which can provide more insight into the bioavailability of B12.

A helpful rule of thumb is to eat about 1.8 times as much iron as people who eat meat. This compensates for the lower absorption of iron from plant sources.

This equates to: 19.8 mg per day for men and 28.8 mg per day for women (before menopause).

You can take iron-rich plant foods like lentils, beans, and nuts, and combine them with vitamin C for better absorption.

You can easily increase your protein intake by combining different protein sources, such as legumes with grains, such as rice and beans.

Aim for 1.08 grams of protein per kilogram of body weight (30% more than a non-plant-based diet to compensate for the reduced intake).

For an adult weighing 75 kg, that means about 81 grams of protein per day.

By using techniques such as soaking, cooking or fermenting you also improve protein absorption.

Take a supplement to replenish your vitamin D levels.

Our Vegan Vitamin D It is derived from algae and is therefore completely vegan. It is specially formulated to supplement deficiencies using high-quality cholecalciferol (D3). This is the most absorbable form of vitamin D and is absorbed much better than D2.

Also, spend at least fifteen minutes outside every day, even when the sun isn't shining brightly. This isn't enough in the Netherlands (especially during the winter months), but it certainly contributes to your vitamin D production!

Eat more seeds and nuts, such as pumpkin and sesame seeds, cashews and almonds, to increase your zinc intake.

As a supplement, I recommend that you also take a high-quality zinc supplement, preferably with easily absorbable zinc forms such as zinc bisglycinate and zinc citrate.

Eat small amounts of fresh or dried seaweed, a natural, plant-based source of iodine.

However, limit this to a maximum of 2-3 times a week, as the amount of iodine in seaweed can be very high and varies greatly, meaning you can easily consume too much.

Too much iodine intake can be harmful and can lead to thyroid problems.

Eat a varied diet, as many plant foods contain small amounts of calcium. These products will help you ensure a good daily intake of (easily absorbable) calcium:

• Tofu – 100 mg per 100 g
• Kale – 231 mg per 100 g
• Chinese cabbage – 125 mg per 100 g
• Tahini – 426 mg per 100 g
• Almonds – 248 mg per 100 g

Eat daily:

• 30 grams of walnuts;
• 12 grams of linseed; or
• 25 ml linseed oil (Caution: do not heat!)

This way, according to the Health Council, you eat enough ALA (1% of your daily calorie intake).

For your DHA, I recommend choosing algal oil, a plant-based alternative to the fish fatty acids EPA and DHA. This way, you'll optimally provide your body with omega-3, without fish or fish-based supplements.

Our Vegan DHA product helps you supplement your vital omega-3 fatty acids in a completely plant-based way. The omega-3 fatty acids in this product are derived from sustainably farmed algae. Two capsules provide you with 400 mg of DHA daily.

Planning meals in advance helps you avoid impulsive and unhealthy food choices, which is especially important on a plant-based diet. Good planning keeps you focused on nutritious, unprocessed options that support your energy levels.

Focus on whole, nutrient-rich foods and avoid highly processed vegan options as much as possible.

Calculate your basal metabolic rate (BMR) and active metabolic rate (AMR). This will help you set a realistic calorie intake goal, preventing you from undereating and becoming fatigued.

It may also be helpful to discuss your diet with an expert so you can avoid long-term deficiencies and fatigue.

For additional support, you can view our collection of vegan supplements in the webshop.