Intermittent Fasting and Hair Loss: What You Need To Know

Intermittent fasting has grown in popularity over the past decade. It’s popular for its weight loss and health benefits. It’s also relatively simple and easy to follow.

Some people, though, have reported they lost hair during intermittent fasting. I also saw many people searching online for information about the link between intermittent fasting and hair loss.

In this article, we’re going to discuss whether there is a link between intermittent fasting and hair loss. We’ll draw insights from experts to get a clearer picture.

Table of Contents

Can intermittent fasting cause hair loss?

Can intermittent fasting cause hair loss? Well, I could hardly find any research on the topic. So, I cannot say that there is a causal relationship between intermittent fasting and hair loss.

Some people might notice hair loss while they’re on intermittent fasting. But these experiences alone don’t prove that fasting causes hair loss.

There’s a bunch of stuff not related to fasting that can affect people’s hair when they fast. This includes factors like existing medications or health issues.

However, the absence of strong empirical evidence does not mean that intermittent fasting cannot cause hair loss. Individual experiences may indicate a potential link.

“The anecdotal reports from individuals experiencing hair loss during fasting periods are noteworthy and deserve further investigation,” said Dr. Ahmad Chaudhry M.B.B.S., a dual board-certified dermatologist at Scandinavian Biolabs.

Dr. Hannah Kopelman, Hair Restoration Surgeon at Kopelman Hair Restoration, echoed a similar opinion: “Personal anecdotes of hair loss during fasting, while not scientific proof, suggest individual variations in response and the multifactorial nature of hair loss.”

So, hypothetically, intermittent fasting could cause hair loss. There are several mechanisms through which this might occur, such as nutritional deficiencies or hormonal changes.

“Intermittent fasting may affect nutrient intake and hormone levels, indirectly impacting hair health. Consuming fewer calories and nutrients during fasting periods could be a factor,” said Barbara Kovalenko, RDN, Nutritional Consultant at Lasta.

How intermittent fasting might contribute to hair loss

So, there’s no strong empirical evidence of a causal link between intermittent fasting and hair loss. But, that doesn’t rule out the possibility of a causal link. Here’s how intermittent fasting might contribute to hair loss:

Nutritional deficiencies

Your hair is primarily made of protein (keratin). Its growth relies on essential nutrients like protein, iron, zinc, biotin, and vitamins A, D, and E.

Eating poorly during intermittent fasting’s eating times could lead to a lack of these essential nutrients. These deficiencies, in turn, could result in hair loss.

“Not getting enough protein, iron, and other nutrients required for hair growth could potentially cause hair to thin or fall out,” said Ana Reisdorf, MS, RD, Founder of The Food Trends.

She further noted, “Another theory is that the body might prioritize vital functions over hair growth during periods of fasting or calorie restriction, leading to increased hair shedding.”


Any major dietary change could stress the body. Intermittent fasting is no exception. Stress can increase cortisol levels, and high cortisol might lead to hair loss.

“The body’s stress response to fasting, marked by elevated cortisol levels, can prematurely push hair follicles into a resting phase, leading to noticeable hair loss,” Dr. Kopelman stated.

Dr. Chaudhry shared a similar view: “Fasting can induce metabolic stress on the body, which may trigger a physiological response known as telogen effluvium, a condition characterized by excessive shedding of hair that is usually temporary and self-resolving.”

Stress could also come from poor sleep quality while doing intermittent fasting. According to a review by McStay et al., research isn’t actually clear on how intermittent fasting affects sleep. But, they noted that one study found a worsening of sleep latency and sleep efficiency in people following a time-restricted eating plan.

Impact on hormones

Earlier, it was noted that intermittent fasting could lead to higher cortisol levels. But, it’s not just cortisol. Intermittent fasting could also affect other hair growth-related hormones.

“Intermittent fasting may potentially affect hormone levels, particularly those related to the regulation of hair growth cycles, such as testosterone, estrogen, and thyroid hormones. Imbalances in these hormones can contribute to hair loss or thinning,” Dr. Chaudhry stated.

This is mainly true for women. Reisdorf elaborates, “Intermittent fasting, especially the more extreme forms, can throw off hormonal balance, particularly for peri- or postmenopausal women, which could result in hair loss.”

Intermittent fasting could also reduce insulin levels. While the effects of insulin level changes on hair are unclear, it’s known that insulin is involved in hair growth.


Intermittent fasting doesn’t always cause dehydration. But it could make it more likely to happen. And dehydration could lead to hair loss.

There are various reasons why some people don’t drink enough water when they fast. For instance, they might forget the cues for drinking, like having a glass of water with their food.

Another reason is a lack of awareness. “Intermittent fasting may lead to dehydration because people don’t drink any liquid for 8-20 hours, as they don’t know that water is not only allowed during fasting but also necessary,” said Kovalenko.

Other possibilities

The factors we’ve just discussed illustrate how intermittent fasting might contribute to hair loss. But hair loss during intermittent fasting could also be due to unrelated things that coincide with the fasting period.

For example, some medications have hair loss as a side effect. Aging could also lead to smaller hair follicles and increased hair fall.

Moreover, hair loss could happen due to underlying scalp issues, such as dandruff, infections, dryness, or inflammation. Recognizing these diverse factors is crucial in dealing with hair loss.

How to prevent hair loss during intermittent fasting

We’ve seen how intermittent fasting could contribute to hair loss. Now, let’s go over some ways to help prevent hair loss during intermittent fasting:

Ensure nutritional adequacy

One way intermittent fasting could lead to hair loss is if you eat poorly during the eating times. This could result in a lack of nutrients that your hair needs.

To prevent this, eat a well-balanced diet during your eating times. Make sure you’re getting enough of the nutrients your hair needs. These include protein, iron, zinc, biotin, and vitamins A, D, and E.

If you’re struggling to get all the nutrients you need from food, you can take supplements to fill in the gaps. But, it’s best to get nutrients from food when possible.

Manage stress

Intermittent fasting could stress your body. And stress could lead to hair loss. So, managing stress is important when doing intermittent fasting.

Avoid extreme methods, as these could increase stress. Do things that could reduce stress, like exercise, yoga, or meditation. Get good sleep, because poor sleep can make stress worse and affect your hormones.

Stay hydrated

Intermittent fasting might increase the risk of dehydration. And dehydration could lead to hair loss. So, make sure you drink enough water when you fast.

Take good care of your hair

As mentioned earlier, hair loss during intermittent fasting could be due to things not linked to the fasting. So, taking good care of your hair could reduce the risk of such hair loss.

Avoid hairstyles that pull on the hair, such as tight braids, ponytails, or buns. Practice good scalp hygiene. Minimize heat styling and harsh chemical treatments.

Dealing with hair loss during intermittent fasting

If you’ve noticed hair loss during intermittent fasting, here are some actions you can take:

  • Make sure your meals have all the nutrients your hair needs. Eat foods rich in protein, iron, zinc, and vitamins. This helps keep your hair healthy.
  • Keep stress low. Engage in simple activities that relax you, like taking a walk or listening to soothing music.
  • Drink enough water. Staying hydrated is good for your hair.
  • Be gentle with your hair. Avoid tight styles that pull on your hair too much. Use hair care products that are nourishing for your scalp and hair. Steer clear of harsh chemicals and treatments.

If hair loss continues, consult a doctor. They can help find out why it’s happening. They might suggest changing your fasting routine or checking for other health issues.

Final thoughts on intermittent fasting and hair loss

We’ve discussed that there’s no strong empirical evidence of a causal link between intermittent fasting and hair loss. But that doesn’t mean intermittent fasting can’t cause hair loss.

Hypothetically, intermittent fasting could cause hair loss through various mechanisms. These include nutritional deficiencies, stress, hormonal changes, and dehydration.

Eating well, keeping stress low, drinking enough water, and taking good care of your hair can all help prevent hair loss. But, if your hair keeps falling out, it’s crucial to see a doctor.

In closing, it’s worth mentioning that intermittent fasting might also benefit hair health. As Dr. Kopelman noted, “Fasting-induced autophagy could theoretically benefit hair by removing damaged cells and promoting renewal, though direct evidence is scarce.”

About the Author

Sasha Lizaveta
  • Save

Sasha Lizaveta is a fitness enthusiast and content manager at She advocates a conservative yet effective approach to fitness. She believes in the power of gradual changes to achieve long-lasting results. When not working out or creating content, she can often be found engrossed in books, playing with her cats, or travelling.

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Copy link