Hair Loss On a Vegan Diet – What You Need to Know

A well-planned vegan diet based mainly on whole and minimally processed plant foods is associated with numerous health benefits, including lower risks of heart disease, high blood pressure, diabetes, and some cancers, to name a few.

So why do some people start losing their hair when following a vegan diet? Is there a link between hair loss and vegan diets?

Can a vegan diet cause hair loss?

Vegan diets are not a direct cause of hair loss.

In fact, a 2022 review¹ found that plant-rich diets include beneficial compounds, such as antioxidants and phytochemicals, that reduce hair loss and stimulate hair growth. These compounds promote hair development by lowering the concentration of free radicals in the skin and encouraging the secretion of growth hormones.

Hair loss is a common problem that also affects individuals who do not follow vegan, vegetarian, or plant-based eating patterns.

As we’ll discuss below, nutrition-related hair loss after going vegan would most likely be due to a poorly planned vegan diet that doesn’t provide an optimal amount of certain nutrients. A healthy, well-planned vegan diet won’t cause hair loss. 

Potential reasons for hair loss on a vegan diet

There are many potential causes of hair loss, such as chronic stress, thyroid dysregulation, and a genetic propensity for early-onset male pattern baldness. Vegan diets that are deficient or too high in certain nutrients may lead to hair loss as well, as with any unbalanced diet. This is why it’s so important for vegans (and non-vegans) to base their diets on nutrient-dense foods.

The role of vitamins and minerals in hair loss isn’t very clear yet. This is because there aren’t many high-quality, randomized controlled trials conducted on this topic. I’ve summarized what we do know below.

Vitamin or mineral deficiency

Deficiencies in the following nutrients are associated with hair loss:

1) Vitamin D 

Evidence suggests vitamin D² supplementation may help people with hair loss who have a diagnosed vitamin D deficiency³, but doesn’t suggest supplementation for people who are not deficient⁴. 

Vegan foods high in vitamin D are limited to irradiated mushrooms and some non-dairy milks and vegan cereals that have had vitamin D added to them, so it can be challenging to get enough vitamin D from food alone. Sunlight is another important source of vitamin D.

If you’re worried that you have a vitamin D deficiency, it’s best to consult your physician and have your vitamin D levels tested.

2) Iron

The link between iron deficiency and hair loss⁵ is still being debated by experts. Hair loss is commonly reported by individuals with iron deficiency, but the effectiveness of iron supplements in improving hair loss is not consistent. This isn’t to say that an iron supplement won’t help if you’re iron deficient – just that it may or may not help reduce hair loss.

Fortunately, vegan diets can provide enough iron. The best vegan sources of iron include blackstrap molasses, tempeh, tofu, beans, and legumes. While not as well-absorbed as iron from animal foods, pairing plant-based foods high in iron with foods high in vitamin C (like fruit, bell peppers, broccoli, or potatoes) helps increase how much iron we can absorb. 

3) Zinc 

Zinc intake can be lower in vegan diets, but deficiencies are actually quite rare – it’s possible that the body can actually adapt to accommodate lower zinc intakes⁶. The relationship between low zinc levels in the blood and hair loss is not clear, as not all people with a zinc deficiency experience hair loss.

It is also unclear how helpful zinc supplements are for reversing hair loss, although they are likely most helpful for people who have an actual zinc deficiency. 

This idea is supported by two different studies. One study⁷ found that zinc supplements in people with hair loss and who were zinc deficient helped improve hair growth, but a double-blind study⁸ in people with hair loss who were not zinc deficient found that zinc supplementation did not help improve hair growth. 

Be cautious of taking a zinc supplement if you do not have a diagnosed deficiency, since excess zinc builds up in the body and can cause symptoms of toxicity, such as nausea, vomiting, and fatigue. Too much zinc⁹ can also interfere with the body’s ability to absorb iron and copper.

Make sure to eat plenty of foods high in zinc, some of which include vegan baked beans, pumpkin seeds, chickpeas, oats, cashews, hemp hearts, almonds, 100% whole grain bread, and fortified cereals.

Biotin is one of the most famous nutrients associated with healthy hair, but I wouldn’t run out and buy a supplement right away. Hair loss is a symptom of severe biotin deficiency¹⁰, an extremely rare deficiency in developed countries since biotin is present in many foods.

Biotin supplements have been shown to help reverse hair loss in children taking certain medications or individuals diagnosed with genetic metabolic disorders, but we don’t have scientific evidence showing that it improves hair growth in other people.To make sure you’re getting enough, I’d focus on eating a variety of vegan foods high in biotin.

4) Folate 

While vegan diets typically provide enough folate, pregnant vegans who don’t get enough folate through their diet or who don’t take a folic acid supplement may become deficient. Individuals suffering from alcoholism or who struggle to eat enough calories may also become deficient.

5) Iodine

An iodine deficiency can lead to hair loss since iodine plays an important role in supporting the thyroid gland. Iodine deficiency can lead to hypothyroidism, a condition that has been linked to hair loss¹¹.

Iodine is not often discussed in relation to vegan diets, but vegan diets can be quite low in iodine. This is because foods with the most iodine tend to be animal-based, such as milk and some seafood.

Some plant-based foods such as seaweed and kelp naturally contain iodine, but the amounts of iodine they contain can vary drastically. Because of this, they aren’t considered to be reliable sources of iodine.

Fortunately, vegans can get enough iodine in their diets by cooking with a half teaspoon of iodized salt per day. Although sea salt and Himalayan pink salt are popular choices, they do not contain iodine unless otherwise labeled as being iodized. If you choose not to use iodized salt or don’t cook enough to use a half teaspoon per day, an iodine supplement is recommended.

You may have noticed a theme here – supplements may help improve hair growth for people who have a deficiency in these specific nutrients, but taking a supplement when you do not have an actual deficiency is not likely to be of much help and is not supported by the scientific evidence available at this time. 

Another vitamin that may be lacking in a poorly planned vegan diet is vitamin B12, but so far having a vitamin B12 deficiency has not been associated¹² with hair loss.

Over-supplementing certain vitamins or minerals

Interestingly, supplementing too much of some vitamins and minerals can also lead to hair loss. It’s a common belief that “more is more” when it comes to these nutrients, leading many people to take supplements when they aren’t really necessary.

When taken in excess, vitamin A, vitamin E, and selenium have all been linked¹³ to hair loss.⁴ Fortunately, vegans typically get enough vitamin A (as beta-carotene, which the body converts to vitamin A) and vitamin E, so supplementation is not necessary. 

On the other hand, selenium¹⁴ can be low in vegan diets¹⁵. Vegans can get enough selenium in their diets and avoid having to supplement by eating plant-based foods high in selenium. The best vegan sources of selenium are Brazil nuts, brown rice, whole wheat bread, baked beans, and oatmeal.

Not getting enough essential fatty acids

It’s also possible that a deficiency in essential fatty acids¹⁶ can contribute to hair loss. There are two types of essential fatty acids: omega-6 and omega-3. Omega-6 fats are found in many plants and vegetable oils, and a deficiency in these fats is extremely rare since they are so abundant in the food supply.

Vegans typically don’t need to worry about not eating enough omega-6 fats, unless they are following a very low-fat diet such as a fruitarian diet.

Adequate amounts of omega-3 fats, however, are a little harder to get in the diet. There are three types of omega-3s: alpha-linolenic acid (ALA), which comes from plants, and docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), which come from animal sources. All three have important health benefits. 

The body can convert ALA to DHA and EPA, but the amount is quite small. Therefore, it’s recommended that vegans get even more ALA than omnivores (3.1 grams for women and 3.6 grams for men per day) to make up for the small conversion rate. If you can’t get enough from food alone, it’s recommended to take an algae-based DHA and EPA supplement.

For vegans, the best food sources of ALA include flax seeds and flax seed oil, walnuts and walnut oil, perilla oil, chia seeds, hemp hearts, canola oil, and soybean oil.

Not eating enough protein

Severe protein deficiency from a low-protein diet is another nutritional factor that can cause hair loss since protein is the major building block for hair.⁵

While vegan diets are capable of providing more than enough protein, vegan diets that are not balanced and that don’t include enough higher-protein foods like beans, legumes, soy foods, whole grains, and nuts can lead to low protein intake and poor hair health.

Subsets of veganism that are more restrictive, like raw veganism or fruitarians, are most at risk for protein deficiency.

Proteins are made up of smaller molecules called amino acids. Supplementation with a specific amino acid called lysine, when combined with iron, has been associated with improvement in hair loss, which may be due to its helpful role in increasing the body’s absorption of iron and zinc.¹⁶

However, it’s not clear whether taking a lysine supplement would be helpful for hair loss when getting enough protein in the diet.

Too few calories overall

If you’re losing hair on a vegan diet, you may not be eating enough vegan high-calorie foods. This can lead to deficiencies in the specific nutrients we have discussed in this post. If this is the case, you may need to eat a larger amount of food or include higher-calorie foods in your diet.

Other considerations for hair loss

Diet is not the only potential reason for losing hair. There are numerous medical conditions¹⁷ and medications that can contribute to hair loss, as can significant physical⁵ and emotional stress¹⁸. 

What to do if you’re losing hair on a vegan diet

If you’re experiencing hair loss and following a vegan diet, speak with your physician and/or dermatologist to see whether it may be due to a medical condition. A registered dietitian can assess your diet for nutritional deficiencies and help you plan balanced vegan meals.

Summary

Hair loss has many potential causes, from medical conditions to nutrition to stress. 

To prevent hair loss on a vegan diet, proper nutrition is key. While a well-planned, balanced vegan diet shouldn’t cause hair loss, a vegan diet lacking certain vitamins, minerals, omega-3 fats, protein, or calories might. 

If you’re experiencing hair loss, be sure to speak with your physician and other healthcare professionals. If nutrition is suspected to be a cause, a registered dietitian can assess your diet for potential deficiencies.

References

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