Can Weight Loss Cause Hair Problems?

Losing weight is almost always a positive decision for your health and appearance. Most people look attractive when they are at a healthy weight for their height, and there’s no quicker way to shut up your doctor than to get your BMI down.

However, there are times when weight loss can have negative temporary effects, especially on our hair.

Hair loss can sometimes occur when people lose weight under specific circumstances, although this can be prevented with the right knowledge and care.

What Is Telogen Effluvium?

There are three stages of the hair growth cycle (1). They are:

  1. Anagen. The active phase of hair growth.
  2. Catagen. The transitional phase.
  3. Telogen. The resting phase.

When our bodies are under stress or low on calories, protein, or nutrients, our hair follicles stay in the resting, rather than a growing, phase. These resting hairs are more easily lost than hair in other phases.

Hair may fall out while washing or brushing, or even fall out with no encouragement at all. This disorder is called telogen effluvium.

When Does Weight Loss Cause Hair Loss?

Healthy and sustainable weight loss – that which is due to a healthy restriction of calories under the direction of your physician – is the only safe way to lose weight while still maintaining your overall health.

However, if you restrict your calories too much or fail to focus on nutrition, you can deal with many side effects including hair loss (2).

In most cases of severe caloric restriction, hair loss does not happen right away. Telogen effluvium usually begins three months after the stress or lack of nutrients. This can be confusing to people as they may never connect the hair loss with the factor that causes it.

This delay is due to the way the hair cycle operates.

Hair goes through several phases. When hair stops growing, in the telogen or resting phase, it takes about three months before it begins to shed.

The process that turns vellus hairs to terminal hairs

Once hair begins to shed, this can last for several months, even if the person has resumed a diet with enough nutrition to support hair growth.

Within a year, most people have regrown their lost hair and have a normal healthy appearance again. Most people never go completely bald from this disorder, although they may have noticeably thinner hair for several months.

How Does Weight Loss Cause Hair Loss?

When we are under stress or not getting enough nutrients (including times when we’re “dieting”) our bodies respond by shutting down unnecessary functions, including hair growth.

There are several deficiencies that have been found to be especially likely to contribute to anorexia hair loss. Protein and calorie malnutrition both commonly cause hair loss in women, but these deficiencies are rare in the modern developed world (3).

When a person’s body is malnourished, such as during an eating disorder, the protein stores in their body become depleted. When this occurs, the body has to make sure that it takes care of essential functions (such as organ function and retaining muscle tissue) above all else.

Our hair, which is made up of a protein called keratin, is not as essential to our body’s functioning (4). So, hair growth stops so the body can focus on keeping that person alive.

Additionally, many people suffer from deficiencies of trace nutrients such as iron, zinc, B vitamins, and certain amino acids. Many researchers believe that these deficiencies are a major cause of telogen effluvium in the modern world (5).

What Diets Are Most Likely to Cause Hair Loss?

Many women with eating disorders like anorexia or bulimia start to see significant hair loss after about a year into their eating disorder.

Almost any diet that restricts calories or protein for an extended period of time can cause hair loss. The body perceives times of calorie or protein restriction as a famine and begins to conserve energy by getting rid of unnecessary functions.

While on dramatic restriction diets, people also may notice changes in their skin and in their fingernails. Skin may become looser and drier, and nails may become more brittle.

In general doctors recommend that people lose weight by calculating their basic caloric needs and then cutting around 10%. This should cause around 0.5 to 2 pounds a week in weight loss even without changes in physical activity.

People can sustain this level of weight loss for a long time without hair loss or other unwanted side effects. However, many people decide to use more drastic diets and fasts because they want quick results. This is when hair loss can become a factor.

Can weight loss cause hair loss even when people take care to get enough calories and nutrients? This is extremely rare. In most cases, only extreme diets and restrictive eating disorders will make people lose hair.

When to See a Doctor

Can weight loss cause hair loss that requires medical attention? The answer to this question is complicated.

In general, there is nothing that a doctor can do to stop telogen effluvium. They may be able to advise you on how to eat more healthily or to manage stress, but they cannot restore your hair. There are currently no treatments for telogen effluvium except to identify and stop the cause.

However, there are several medical conditions that can mimic weight-induced hair loss in women.

For example, hypothyroidism can cause hair loss as well as a variety of other symptoms (6).

Similarly, toxin exposure, excess vitamin A, and other reversible medical conditions can cause hair loss. It is important to see a doctor if your hair loss does not appear to resolve in a few months, or if you are having other symptoms that are concerning.

If you have an eating disorder, there is help. Hair loss is just one of many negative consequences of rapid weight loss and disordered eating; anorexia and bulimia are deadly conditions. You are not alone.

Can Hair Loss Be Prevented?

If you want to lose weight without losing hair, there are a few measures you can take. While these will not guarantee a thick, full mane, they will give you a greater chance of keeping your hair volume while losing weight.

Foods that contain high amounts of vitamin B12.

  • Restrict calories only enough to lose two pounds every week.
  • Eat enough protein to sustain good hair growth and tissue strength. There are many calculators online that can help you decide how much is enough for your specific height, frame, and weight.
  • Eat a wide variety of foods, including vegetables. Take a multivitamin if you are concerned about getting enough nutrients to sustain healthy hair.
  • Take a biotin supplement. Biotin is essential in the production of keratin, which plays a huge role in the composition of hair (7).
  • Care for hair in a way that is gentle. Avoid vigorous toweling or other rough treatment and aggressive styling that could damage or pull out hair.

These steps will not only prevent hair loss, but can actually cause you to gain hair. In addition, they will ensure that you have increased shine and length, which is all a girl could ask for!

Healthy Options for Regrowing Hair

The most powerful thing that you can do to regrow hair is to stop doing whatever is making it fall out. Take the above tips on healthy dieting seriously. For most people, these tips will ensure fast and healthy hair regrowth.

Although it will take time for hair to regrow, there are ways to help support the process.

Many people have gone through weight loss related hair loss. While this can be concerning and even scary, it usually is minor and will resolve quickly. Although it can be difficult, keeping a healthy diet and stress-free lifestyle is key to preventing this disorder.

The best diet for hair loss contains lots of vitamins and minerals

You may feel conflicted because you want to lose weight quickly, but you don’t want to lose any more hair. I hope I’ve given you reason to pause and consider your weight loss strategy; crash and fad diets are gonna spell danger for your precious tresses!


There are healthy and sustainable ways to lose weight.

Is hair loss possible when weight loss is done in a safe way? Sometimes. But it’s often temporary.

On the other hand, severe caloric restriction and nutrient deficiency can lead to a type of hair loss known as telogen effluvium. And the longer the restriction and deficiency continues, the longer the hair loss will continue.

Fortunately, it is possible to continue to lose weight while also reducing – and even stopping – telogen effluvium. This includes healthy caloric restriction, a diet of nutrient-rich foods, nutrient supplementation, and physical activity.

Do you have questions about weight loss and its effects on your hair? Drop a comment down below!

40 thoughts on “Can Weight Loss Cause Hair Problems?”

  1. Wow! Excellent information and very well presented. This article will surely help a lot of people.

  2. Wow, interesting article! I did not know that crash dieting could cause hair loss. I don’t pay much attention to my diet and don’t usually bother with fresh veggies as they are too much trouble too deal with. I’ve recently noticed that my hair is thinning in places – now I know why!
    Thanks for the good advice!

  3. Hi Joy – thanks for sharing your experience and thoughts. Definitely slow down any weight loss efforts and your hair will thank you later! 🙂

  4. Really informative. The rosemary is an eye opener to me, personally! I’m starting to lose some hair by my bangs, this is a great resource for me 🙂

  5. What a great and informative read. Normally we take loss of appetite/anorexia and hair loss as two separate entities, this is really interesting to know that anorexia and weight loss can actually cause hair loss as well. You have mentioned all the important points regarding this issue, i think it is all about living a healthy life, with balance diet, more physical activities and be happy. All these contributes to our good physical and mental health which includes healthy hair as well. Thank you for sharing this amazing read:)

  6. Gosh, I had no idea that weight loss could cause hair loss. Thankfully my weight reduction has been steady and my hair remains thick and healthy. I must look into Biotin further as I keep coming across it, like its calling to me!

  7. This is so interesting. I’ve never heard of Telogen effluvium. I also didn’t realize weight loss could cause hair loss or thinning hair. Good points to lose only a couple pounds a week instead of the extreme. Great article, thank you!

  8. Thanks for reading, Gabriella! One study found that Rosemary oil is as effective as Rogaine….and it’s a lot less smelly, so I’m a fan 🙂

  9. Thanks for sharing your thoughts, Mary! I agree, we think about weight loss as the be-all end-all, but rapid weight loss does come with a price, particularly for our poor beleaguered manes.

  10. Hi Lace- thanks for sharing your thoughts! Good to know you’re doing it the slow and steady way, and that you’ve experienced no hair loss. Biotin is good not just for hair health but also for skin and nails, totally worth checking it out!

  11. Thanks for sharing your thoughts, Tammy! Yeah, as much as we all want to lose all our extra weight like yesterday, for those of us also struggling with hair loss, it’s a balance of factors and slow and steady is the way to go.

  12. Wow, that is crazy, there is always something out there you can learn. Who would have thought that losing weight, incorrectly, could cause you to lose hair? I guess it does make sense though. I am so glad you take the time to inform us of important things like this. I will be sure to take your advice and not lose no more than 2 lbs per week, eat enough protein and such. I am definitely going to share this article. Keep up the great work!

  13. I always thought that the more weight you put on, the more chance there is for hair loss, after reading this post I now know I was totally wrong so thanks for that 🙂

  14. Really interesting post, and it’s good to see hair loss from another angle. Most people don’t consider the fact that it could very well be their diet that is causing hair loss issues. Crash dieting is just bad for every system in your body so why should the hair be any different?
    I’ve had hair loss issues, and still do have but I have a good diet so it must be down to other things such as having a slightly slow thyroid and STRESS. That’s one of the worst things. Thanks for the tips and advice about how to correct these issues. I always learn something new with your posts, and today I’ve learnt that I need to start taking Biotin. Thanks.

  15. I totally agree with you info!
    I have a stomach condition that causes it to produce to much acid, thus hurting the stomach lining and eventually causing irregularity on my eating patterns, as there’s times I can’t eat for days while in treatment…it’s awful. But what I’m getting to is that I loose weight very easily (not in a healthy way) and I noticed how much it affects all my body but most of all the hair loss….which then causes me more stress and I’m on an endless cycle. I’m glad you explained with so much details the ways and how it happens, I always love the useful information 🙂

  16. I feel like whenever i’m training a lot and putting lots of stress on my body it tends to make me lose some hair.

    I think the combination of sweat and the sun contribute to a more weak set of hair but I can totally see how weight loss would translate with that.

    Very informative post and I thoroughly enjoyed reading it:)!

    Thanks Penelope!

  17. Great article! I’ve always heard that extreme dieting could cause things like brittle nails or thinning hair, but I wasn’t familiar with the term Telogen Effluvium. I liked how you explained all the possible causes of hair loss, then your experience on what to keep hair healthy. Right now, I’m taking fish oil daily and using a caster oil/olive oil/peppermint oil scalp mask every 3 nights for keeping dem locks healthy! Thanks for sharing!

  18. Thanks for reading and sharing your thoughts, Sarah! I’ve heard castor oil is good for hair loss, I think I’m gonna investigate that one a bit more.

  19. Thanks for sharing your undoubtedly unpleasant experience with this issue, Arlet! Hopefully this blog can arm you with some tricks to fight the fallout when your condition is flaring up!!

  20. Hi Stefanie, thanks so much for checking in and sharing your thoughts. SO many different factors in our hair loss, lately I’ve been trying to explore more of the medical conditions behind hair loss on this blog, and I’m glad you’ve been enjoying the info!

  21. Thanks for reading and sharing the info, Melissa! As women, I know we get impatient on our diets and wanna lose weight quickly, but for those of us struggling with hair loss it’s a bad call. Always, slow and steady wins the race 🙂

  22. I have experienced hair loss with weight loss and never knew what it was called. I’m glad I came across this so I can get a better understanding.

  23. Hi Penny,

    Wonderful post again! Its funny how all the ills of our body can be fixed by what we put into them! Good healthy plant based diet, lots of exercise, sunshine, fresh air, meditation, fasting. It really is important to manage your health when issues arrive.

    I guess when we go on crazy crash diets we have to expects some side effects. I love the way you explain everything in your articles it makes it so easy to understand. Thanks for all you do,



  24. It makes perfect sense that protein or lack of protein would ultimately cause hair loss. They are the building blocks of life and I do notice a noticeable increase in hair growth when I drink protein drinks 3-4 times a day. Never really thought about how the process of losing hair actually happens.

    What about medications though? Are there some medications that are known to cause hair loss?

  25. I love how everytime I visit your site I learn something new. I like that you include the scientific part of it, describe what the problem is, and how to prevent it but most importantly how you share your own experience. Now that I think back, my hair was breaking a lot when I was on a strict diet. Now I know that there are healthy options to regrow hair. Thanks a lot for sharing this and keep up the good work!

  26. Thanks for sharing your feedback, Kevin! It is incredible how much nature and simplicity can cure…we’ve gotten so divorced from the simple and straightforward solutions in our modern life, it never hurts to be reminded of them!

  27. Thanks for sharing your thoughts and experiences, Dira! I’m happy to hear everyone’s feedback reinforce the thesis of this article…seems like lots of us experienced weaker and thinning hair on those crazy crash diets!

  28. Another great article. I had no idea that losing weight and hair loss are related. Now everything all make sense. I love visiting your site. I learned new thing every time I come to your site. The information is well written and nicely presented. Thank you for sharing. I am looking forward to your next article.

  29. Wow! I had never considered that weightloss caused hair loss. Although after reading your very informative post it makes total sense. Thank you for this and I am going to ensure I have the right calorie deficit in my weightloss plan!

  30. Thanks for sharing your thoughts and feedback, Megan! As much as it’s tempting to lose weight fast, we gotta protect and prioritize our hair, too!

  31. Thank you for sharing your thoughts and the kind words, I really appreciate it, and am glad you learned something new from this post.

  32. I really wasn’t aware that weight loss caused a loss of hair, but when you read on it really does make so much sense, particularly for those who are dieting to the extreme and drastically reducing their nutrient intake. It makes so much sense to make sure that weight loss is done slowly, it gives the body time to adjust and will most likely be more sustainable.
    I think most people who have a healthy head of hair might take it for granted, but it really does pay off to take care of the hair you have got!

  33. Glad that you found the information in this blog helpful, thank you for reading and sharing your thoughts~!

  34. Hi Garen! thanks for the great insight and question. yes, there are absolutely medications known to cause hair loss, and I’ve blogged about a common culprit here, which is incidentally one that I have to take daily for my thyroid disorder. There are still ways to mitigate the damage…keep reading!

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