Eating Disorder Recovery Exercise / Compulsive Movement Helping Family / Carers Understand Other ED Behaviours Restriction & Fear Foods Weight Changes

The Metabolism And Eating Disorders



A question that arises regularly from people in recovery from an eating disorder (ED) is in respect to issues around body metabolism, in terms of what it is; what hypermetabolism is; whether they have ‘broken’ their metabolism and what it means for their recovery.

I hope to address a lot of the common concerns people experience around this topic in this post.

If you have had or have disordered eating then it is likely that your body metabolism has been affected at various points, impacting on your body’s ability at those times to lose or gain weight and to function at an optimal level.

What Is The Body Metabolism?

The metabolism describes all the chemical processes that go on continuously inside your body to keep you alive and well; your organs functioning so that your heart beats and lungs work to breathe, cells repair, your gut digests food and your brain can think.

In every moment, your body is undertaking thousands of chemical reactions to keep your cells functioning and to ensure that you stay alive!

To stay alive, the body needs essential energy and nutrients which come from the food you eat and the fluids you drink.  The body then breaks these foods and drinks down (which in itself takes energy) to release the energy from them and this energy is then used for all those bodily functions that you need to have working well in order to be as optimally healthy as possible.

Basal Metabolic Rate

Even when completely resting, your body is using up calories to just maintain its basic function (as described above).

The minimum amount of energy required to carry out these resting chemical processes is called the basal metabolic rate (BMR) which accounts for anything between 60% and 75% of the body’s daily energy requirements (in a sedentary person) depending on other factors such as age, lifestyle, the body make up and your environment.

What Happens When The Body Has Insufficient Energy

When the body is starved (i.e. the energy consumed is lower than the energy required), its tissue, including muscle and fat, is lost and this triggers a reduction in the metabolic rate.

If the body does not have sufficient energy intake, it will try to preserve every bit of energy it does get in any way it can.  This is commonly referred to when speaking about eating disorders and malnutrition as the body going into ‘starvation mode’.

The mechanisms the body uses when in starvation mode in order to stretch out the little energy it has been given include providing less nutrients to hair, skin and nails (so they become dry and brittle); slowing the heart rate down, slowing down the gut motility (leading to digestive problems, feeling overly full on little intake and potential constipation) and reducing the body temperature (often leaving the person feeling cold most of the time).  

This ultimate drop in the BMR means that the body needs less calories to function but is functioning at a very basic level, ultimately just doing all it can to stay alive.

A drop in BMR will happen in the body when the energy intake is dropped for any reason.  Therefore, in eating disorders, it will occur when the person is not eating sufficiently (restricting) or when a person is compensating for what they are eating (e.g. via exercise, purging etc).  

However, the same response occurs when people drop their intake for other reasons, including people who diet and this explains why those who diet may initially lose weight rapidly but after a couple of weeks of dieting will find it much harder to sustain weight loss as their BMR has fallen and they are using less baseline energy.

Once a person who has had a low BMR starts to eat more again and provide their body with the energy it requires, the metabolism will start to rise again and as the body’s systems return to working at their optimal and healthiest levels, the body will require more energy (food) just to keep maintaining these basic functions.

The Metabolism In Eating Disorder Recovery

In eating disorder recovery weight restoration and nutrition are key components to treatment, in order to restore the person’s body to its natural set point weight.  

This very necessary weight gain in recovery results in ultimate improvements in the physiological and psychological complications of semi starvation.

In order to achieve weight gain, people with an eating disorder ultimately need to increase their dietary intake to a level that is above that required for their BMR AND daily activities AND then enough to restore weight in terms of tissue re-development and internal repairs.  

To achieve regular weight gain and find their own unique set point weight (for ultimate long lasting health), people recovering from eating disorders generally need an escalating calorie intake.

Hypermetabolism in Eating Disorder Recovery

Research has found that women with eating disorders tend not to gain weight if fed the energy requirements of healthy adult women who have never had an eating disorder.  Instead people in recovery from eating disorders tend to have much larger energy requirements and need to increase their intake more and more for sustained weight gain.

The reason for this can be explained since people with eating disorders are often found to become hypermetabolic once they increase their dietary intake sufficiently.  This is where their metabolic rate becomes much higher than the average rate expected in a healthy adult woman.

Hypermetabolism in people recovering from an eating disorder results in them potentially losing weight more easily (if not careful) and their energy (food) requirements to gain weight is much more than most ‘normal’ people would need.


People with eating disorders have also been found to commonly become hyperthermic during their recovery.  This is where they convert more of their energy intake to heat than healthy people, rather than use the excess intake to build tissues.  As a result, during nutritional rehabilitation, people with an eating disorder often become hot and sweaty.  This is commonly worse at night and it is not unusual for people in eating disorder recovery to wake in the night sweating and with soaking sheets.

Conversely, healthy individuals who have never had an eating disorder will generally drop their body temperature at night and so preserve energy at this time.

It is thought that the hyperthermic effect during nutritional rehabilitation results in up to 30% of energy input being lost (in healthy people the rate is generally around 14%).

Weight Gain in Terms of Fat vs Other Tissues In Recovery

In order to fully weight restore and achieve a lasting recovery, the body needs to restore fat mass AND fat free mass.  

To gain fat free mass the energy requirement is several times greater than that needed to gain fat mass but in order to achieve a full and lasting eating disorder recovery (reaching your body’s genetic set point weight), it is essential to go through the nutritional rehabilitation process and fully restore both body mass types.  As the body gains weight and restores in recovery, it will gain a greater proportion of fat mass first and the final (crucial) stages of weight restoration will then include building more essential muscles and tissues, which as stated above, takes even more energy.  Therefore, this vital latter stage of weight restoration and physical healing can be even harder to achieve as it needs more food (energy) to achieve the same rates of gain that were made earlier in the process.

What Happens To The Metabolism After Weight Restoration?

After the nutritional rehabilitation phase of eating disorder recovery and once the person is fully weight restored, it has frequently been reported that their energy requirements remain high.  Those with an eating disorder and in recovery are frequently found to still be very energy inefficient and need greater calorie intakes than healthy controls just to maintain their restored weight.  

It is not uncommon that nutritionally rehabilitated people need up to twice the daily calorie intake to healthy adults just to maintain weight due to ongoing hypermetabolism.  

This hypermetabolism can settle down in 6 months of nutritional rehabilitation but it is widely recommended that the best chance of long term weight maintenance in recovery (reducing the risk of any relapse) is to persist with high calorie intake long term.

What Does All This Mean If You Are In Recovery From An Eating Disorder?

For anyone in recovery from an eating disorder it is likely that once you are providing your body with sufficient energy on a daily basis (i.e. high calorie intakes) your body metabolism will speed up to a greater rate than in healthy individuals.

Therefore, you will likely find that your energy requirements to keep gaining weight will keep rising and as you start to fully restore both fat and fat free mass towards the the end of weight restoration, your energy needs are likely to be extremely high.  

During nutritional rehabilitation you might find that you are warm or hot a lot of the time and experience night sweats or clamminess.  

You will possibly notice a rise in your heart rate.  

You should also start to notice better nails, hair and skin.  

Once you have fully weight restored, the level of intake (food) you need every day to maintain this healthy weight is likely to be significantly higher than healthy adults of your age and build and this higher energy need could continue for a significant amount of time.

In conclusion, the amount of food needed now to restore weight and once weight restored is likely to be much more than you think and your body will respond to the energy levels it is given.  

Therefore, eat large amounts to nutritionally rehabilitate and keep eating large amounts well into recovery!

And Finally, But.. Is My Metabolism Broken??

One question that is often posed from people in recovery from restrictive eating disorders who have been weight restoring while still actively restricting or actively exercising is – 

…‘but what will happen now if I do stop restricting or stop exercising?’ 

‘I am already back at a ‘healthy weight’ – won’t I just then become massively overweight?  Have I broken my metabolism forever??’

If this describes your situation or your fears then please don’t despair – you are not broken!  

It is very likely that as you have still been restricting your intake and exercising then your body metabolism has remained in ‘starvation mode’ (very low) to preserve what it is being given.  Your body used the small amount of surplus energy you did provide it with to restore your weight and try to repair tissues causing some weight gain but your body recognised that there was still insufficient energy supply to allow it to speed up the base metabolism and function at its optimum.

This can still be changed.  

If you start to eat more now –  stop restricting your dietary intake and give your body the amount of fuel it desperately still needs and if you stop compensating for what you are eating (if you are still exercising) then your body will respond.  

Your body will learn to trust that fuel is in sufficient supply so it can ‘afford’ to work at a more optimal level and your metabolism will, as discussed earlier in this article, respond and speed up.   It is never too late for this to occur! 

Consistently eat unrestrictedly, without compensating and your metabolism and body weight will naturally settle back at your genetic set point which your body will then fight to maintain.


Marzola et al.  Nutritional Rehabilitation in Anorexia Nervosa: review of the literature and implications for treatment.  BMC Psychiatry (2013) 13:290

16 replies on “The Metabolism And Eating Disorders”

Hello, I have always had a very good
metabolism, (before my eating disorder) now, when I’m in recovery there’s this one question that keeps coming back and that is: will my metabolism be as good as it was before my eating disorder?


Yes. If you do recovery right then as I describe in the post you will probably go into higher metabolism for a time and then it will settle back to a ‘normal’ level after some time.
The question is though, does it matter? Fears about metabolism never healing come from the eating disorder and fear of weight gain. Face those doubts and fears with a ‘I’m recovering and doing this no matter what happens because it will be so much better than life is now!!’ X


Hi Helly. Thanks for another interesting article.

I feel as if my recovery process has been a bit unusual in that most of my weight gain occurred whilst I was quite heavily restricting. My body weight is now almost double my LW. I did get my menses back after 10+ years being amenorrheic so I must be eating sufficiently to main that at least!
I still experience a low HR and cognitive issues (brain fog, forgetting words, short-fuse, etc) as well as low energy. I’ve never really experienced hypermetabolism or extreme hunger. I actually haven’t experienced too many symptoms of ‘recovery’ at all apart from hormonal imbalances/fluctuations/second puberty 😂🙈

Do you think it’s necessary to force oneself to say eat over 2000cals in recovery? I feel it is unnecessary due to my substantial weight gain/return of menses but maybe that’s where I’ve gone wrong. Also fullness is still an issue due to my Emetophobia…

I’m now 4 years into recovery and wonder if this is it for me. I kind of hoped it would feel better than this 😂

Any insights or suggestions would be much appreciated.
Thanks for all that you do.
With respect 🦋


Hey there,
It sounds like you have done what so many people do and that is gain weight (which isn’t recovery) in a heavily restrictive way. 2000 calories is a restrictive diet for any adult (don’t believe the low government guidelines) and I very much suspect that even within that amount you were eating, you were also very restrictive in the what and when etc.
Menses is not a sign at all of recovery or that the body is functioning optimally. Some people at extreme low weights still maintain a period so it’s not a true guide of how well the body is functioning or restoring.
The fact you still have a low heart rate, brain fog and low energy, never had high hunger or other recovery side effects really indicates to me that you are very much still in ‘starvation mode’ (no matter what your brain is telling you about your weight!).
The good news is that you can still overcome this and find that life is much much better than now but it will take consistently eating a lot more in non restrictive ways (not just eating more but also eating the things that truly terrify you)…
I know the emetophobia is an additional complication for you but you can get past that in the same way people have to overcome other fears in recovery (by facing them head on).
Eat and eat now; let your body and metabolism really heal and I think you will find your brain rewiring and that the brain fog also improves.
Helly x

Liked by 1 person

I just want to thank you because when I woke up this morning it was evident how confronted I felt about the prospect of eating more, increasing calories and potentially gaining more weight. I actually thought that I’d surpassed that ‘stage’ of recovery- but obviously not.
Perhaps my recovery has just stagnated – and the ED is just hiding behind a false sense of comfort.
Your responses have prompted me to realise that I’m not as far forward as I assumed and there is still a lot of groundwork to be done – so thank you.
I feel a little guilty taking so much of your time – I did actually look at booking a session (so I can at least reimburse you for your time!) but your books are full – unsurprisingly because you’re very insightful and knowledgeable.

Thanks for taking the time to respond to my messages. I truly appreciate it.


No thanks necessary at all!
It is good that you have come to the awareness of what still needs to be addressed for your recovery. If there is such a high level of discomfort at the thought of eating more, gaining more weight then it does sound like a very active eating disorder, perhaps one you could deny by convincing yourself that you were ‘eating enough’, even if that ‘enough’ was still very much within restrictive limits, types and situations. I always say that when you have the insight of what needs to be addressed then you are part way there and now is the work of doing it… which means finding every food that scares you and munching your way through it with delight, knowing it is the best thing to just find out once and for all if the recovered life might just be better than the ED one has been! xx

Liked by 1 person

I truly appreciate your words and the concepts you have mentioned. Definitely helpful!

Quick question- how long did it take your hormones to rebalance?
Since my menses has returned I’m super-reactive to lots of foods (mainly nasal congestion and itching – no actual allergies though!) and have sinusitis flares, hot flashes, pruritis and lots of other PMS symptoms which are definitely impeding my recovery progress. When I eat I legit feel like I can’t breathe but allergy tests came up negative. Did you ever experience any hormonal issues during the recovery process? Feel free not to share as it’s quite personal …

I’m honestly not sure if I’m in puberty or perimenopause! 😂
I know you’re probably busy so if you don’t have time to respond that’s totally okay! 💗🦋


Every person with hormones is different and it is hard to say how long these things take because so much impacts on our hormones above and beyond recovery things even. While you are going through recovery though, your hormones will be all over the place and more up and down than a teenager in puberty because your body doesn’t know whether to switch things back on to work again or to keep things suppressed…
With the breathing difficulties when eating, that could be any number of things beyond hormones too… anxiety and stress being a key one but also related to a smaller stomach pressing on your diaphragm or other things.
At the end of the day, I would say that you don’t need to know what is causing what symptoms at this point in time. Allow yourself to eat and rest and let your body trust you to feed it sufficiently and consistently for a good period of time and then re-assess where your body and symptoms are at… I suspect at that point, when things are all functioning optimally because you are feeding yourself really well and fully physically restored, that a lot of these symptoms will have resolved by themselves. xx

Liked by 1 person

Your calm reassurance is so comforting.
You are likely correct with your suggestions. My hormones are still quite erratic, I have chronically elevated anxiety levels and there are also I’d assume a lot of subconscious beliefs around food (I believe my body can’t tolerate dairy, soy and gluten well, eating bread affects my breathing, sugar feeds bacteria, salty foods are bad, etc. and there are highly likely many others that I’m not even aware of) So. Many. Beliefs.
It’s so difficult to ascertain if symptoms are provoked by a genuinely physical reaction or precipitated by thoughts!!!

Ugh. Anyway. You’re possibly right – so I guess for the time being I’ll have to try and overlook the symptoms, ‘just keep swimming’ and hope for the best.
Your calming, perceptive and supportive words are a true blessing. Thank you Helly.
Hope you are doing well 🦋🌻


There certainly are a lot of strong beliefs there driving your eating disorder at the moment. I would say that you need to challenge them all by literally eating everything. Yes, you will experience physical discomfort and side effects because your body has been denied so many food types for so long and so won’t have the necessary digestive enzymes etc at first but the only way to let your body learn how to digest those foods again is by eating them, tolerating the physical and mental discomfort in the short term and coming through the other side in a much much better place in every way.
Eat everything and bash those fears and disordered beliefs down! xx


Thanks so much for taking the time to reply. I appreciate and respect your insightful response.
Your are likely correct. Perhaps this is why I feel so stuck.
I really enjoy your interesting recovery blogs.
Thanks again.

Ps. I’m unable to delete the duplicate comments in this post. Are you able to do it from your end please? There is one from Tip if the Asperg above that is a duplicate of the comment from Tip. Thanks 🙏🏽


Not a problem – I really appreciate you taking the time to read and comment!
Definitely get eating more and just see how your body responds…. yes you might gain a bit more weight but recovery means being ok about that and if it means getting a free mind, a free life and a body that actually is healthier then surely it has to be worth it! x

Liked by 1 person

I think deep down maybe I know this…but my brain is still yelling- but you’re already ‘overweight’, ‘you already gained so much weight’, ‘what if you just get fatter but don’t feel better’ blah, blah, blah. ED rambles are so boring, right!? 😂
Boring, but terribly convincing at times!


Boring and predictable…
I could predict immediately that that was what your brain was going to be saying to you because this illness is so boring and uses the same old stories for everyone!
Therefore, because you know that these thoughts are just powerful symptoms of the illness, you can choose to experiment with ignoring them and just see what happens. What if you get fatter and don’t feel better? Really, is that the worse possible outcome and if so isn’t it worth the risk?

Liked by 1 person

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s