Why We (temporarily) Feel Worse When Eating Healthy


In the spirit of CARE, let’s start this conversation by having you envision a single cell in your body.

Cells look a lot like a pin cushion. 

The surface of cells aren’t smooth at all, but rather, are full of individual receptors (the pins).  These receptors are critical to influencing how that cell behaves.

Depending on what the receptor communicates to the cell, that cell could start making more of something, it could start making less, it could speed up or slow down – and your overall health, risk of disease, and how you just plain feel that day depends on this activity.

So what determines what the receptor will communicate to the cell?

This includes, but is not limited to, what chemical nestles right onto the top of the receptor or how much of different chemicals are available in your blood.

These chemicals can include good-for-us substances like:

  • nutrients
  • hormones
  • and neurotransmitters

Or they can be not-good-for-us substances like:

  • nicotine
  • excess caffeine and alcohol
  • food additives and colorings (like MSG)
  • or excess sodium or glucose/sugar

Every minute of every day your cells try to make the best decision based on the ‘information’ or tools that you provide them.

Overconsumption, excess intake of food chemicals and drugs, and high stress all contribute to lots of not-good-for-us substances available in the blood.  These substances wreak havoc on the information available to those receptors.

The old saying of ‘garbage in, garbage out’ applies here.  When you only give your cells garbage to work with, you feel like garbage.

But interestingly, over time you start to build a tolerance to how this dysfunction feels.

In this ironic twist, eating too much and too many chemically-based ‘foods’ actually does make you feel better.

This is no different than a smoker.  The first time a smoker puffs on a cigarette, the reaction from the body is severe.  There is violent coughing, immediate lightheadedness, some GI discomfort.  But by that third or fourth day, those selfless receptors have adapted to being bullied by nicotine nestling right on top of it.  Having nicotine there (even though harmful) becomes its new normal.  It creates workarounds and compromises ideal functioning, but you now interpret this as ‘feeling good’.

That cigarette no longer makes you cough, it makes you feel pleasure.

Until you remove it…


This picks up the story with our subject of why we temporarily feel worse when starting to eat healthy.

You (meaning your receptors and cells) have adapted to higher amounts of not-good-for-you substances in chemical-based foods and overconsumption.  This has become your new normal.

You, in that ironic twist, feel better here.

Until you remove them…


Just like the smoker, your receptors adjusted to dysfunction.

Their normal is now defined by access to these substances.  When you remove them, you change the information available to them again altering how each cell responds.  Initially, that feels bad – even though it is good.

How long it takes for those receptors and cells (and ultimately you) to recover depends on so many factors (genetics, nutritional status, environment, social and physical stress, how many changes you made at once), but on average in as little as three to four days you will start to feel better from eating healthier.

Let’s Recap

Timeline of what happens and why you feel worse when starting to eat healthy:

  • Removing chemical ‘foods’ and overconsumption means that your cell receptors no longer have access to those not-good-for-you substances.
  • Many of these chemicals stimulated cells (like with MSG) or amplified the releases of feel-good neurotransmitters like dopamine and serotonin.  This alone will affect mood, energy levels, and sleep.
  • Increased circulation from more activity and better hydration (which increases the availability of oxygen and nutrients) combined with the removal of excess chemicals in the blood (like glucose and sodium) can create vascular changes (even if good for you) that can result in a headache.
  • Healthy changes also decrease the total stress burden on the body. Your efforts to increase physical activity and decrease chemicals, including caffeine and alcohol, will result in decreased circulating stress hormones, like cortisol, which is a natural steroid that has anti-inflammatory properties (just like the prescription).  Short-term, good for us.  Long-term, bad for us.  Bringing stress hormone levels down will initially alter the immune system which you could experience as getting a cold or just feeling lousy.  This happens often when people go on vacation – they finally reduce their stress levels and then get sick right away.
  • The liver, kidneys, and skin are all involved in and responsible for the natural detoxification of all these changes to hormone levels (like cortisol and insulin) and other chemicals. As the liver, kidneys, and skin respond, this can lead to breakouts or skin rashes.

The Great News

The great news with lifestyle changes, like increased nutrient-richness, increased activity, and increased stress management and recovery, is that these changes are the foundation needed to make more challenging healthy changes (like quitting smoking).  Our cells thrive quickly when we remove chemicals and give them tools to heal versus harm.

  • Receptors will become more sensitive to things like insulin, sodium, and hormones which over time will regulate blood glucose and blood pressure.
  • As blood glucose is better regulated and consumption moderated, metabolism gets more efficient at utilizing stored adipose tissue (fat) for energy.
  • The decreased burden on the liver results in better regulation of lipids (like cholesterol) and sex hormones.
  • The increased circulation and vascular changes move from causing headaches to decreasing risk of heart disease and improving cognition.

So how do you make it through (temporarily) feeling worse to feeling good?

Use this time to increase awareness of your body; increase mindfulness.

Appreciate the calming feeling of these lifestyle choices that we often misinterpret as sluggish or low energy.  We are a society that spends billions of dollars to override our natural cues to rest.  Our right hand spends billions on stimulants while our left spends billions on relaxation and sleep aids.  We can’t even distinguish between the two anymore when we remove all chemicals and overconsumption.

This time, appreciate the calm.

Appreciate that you feel sluggish because your body is finally putting resources into healing.  Finally, let your body rest and heal.  You will be rewarded with greater strength than you thought possible.


Teri Rose, CARE Nutritionist and Program Director


  1. Samantha Trollop

    It’s January 5th and I’m starting my 5th day of clean eating. Over the festive period I consumed huge amounts of alcohol, mostly beer, and ate a ton of junk food. I ate absolutely anything I wanted. I don’t have a huge appetite so the quantities weren’t huge but the quality was truly awful. Burgers, pizzas, potato chips, curries and ots of chocolate and biscuits too. Throughout December the vast majority of my calorie intake was junk food and alcohol. However I did exercise regularly and managed to maintain a healthy weight. Even at the end of December, despite putting on a couple of kilos, my BMI and blood pressure were both well the healthy range. I should also stress that even prior to December I regularly ate junk food only I regulated it better. I’d have one portion of junk food and eat healthy the rest of the day. However as of Jan 1st I’ve gone completely cold turkey on junk food and alcohol. I’ve also gone back to my 16:8 intermittent fasting program where I only eat within a 8 hour window. I was doing this prior to December so I’m well used to it. Now. Giving up the alcohol is easy. I don’t miss it. I’m glad for the break. The diet however is really difficult. I’m only eating whole foods and consuming lots of fruits and vegetables. Nuts and seeds. Oatmeal. Oily fish. Beans, pulses etc. My diet is on point. On paper I should be feeling great. And for the first few days I really was. It felt great to be doing something good for my body. But every day is getting harder! Physically I feel good. But when it comes to dinner time the thought of these healthy meals physically makes me feel sick! All I want is junk food. And my healthy meals are normally quite delicious. Back when I was eating them along with junk food they were absolutely fine. But without any junk food entering my system they’re becoming less and less appealing. My only guess is this is some form of withdrawal symptoms. I am denying my body what it is used to and it doesn’t like it. As it’s only five days in I’ll continue with what I’m doing. But the feeling of wanting to gag and throw up makes it more and more difficult every day. Praying for a breakthrough

  2. carlton

    I am a DV and decided to go 100% clean eating about a month ago. For the past few years my diet has been about 60-70% good. I would like to say I feel great, but overall there isnt much difference.

    Checking my BG levels, they have went down and my BP is also great, but the “feeling” of being healthier is just not there. I dont know what it is, maybe its all in my mind. I wont stop eating right because my family has a history of diabetes and I would rather not go through that!

  3. Laura

    I know this is an old thread but i wanted to put this up for anyone who needs eat. Meat and dairy are not good for you. Also if you are eating alot of fruit and veg that is not organic this is also bad, you’re ingesting all those chemicals. Alot of vegan and veggie stuff isnt good either that is processed. Watch a program called what the health. It will change your life. I was also wondering why I was feeling so crap for years because I was eating what i thought was healthy, eggs, fish, lean meat etc, fruits and veggies. Once i cut meat and dairy out, processed foods, changed to organic and added herbs to my diet it all changed! Some times what we think is healthy really isnt, we’ve been taught wrongly.

    1. Joseph

      I am gonna watch that program you recommended. I recently changed my diet totally as I’m taking a bio class this semester, becoming aware of what’s going on inside our bodies in detail really made an impression on me. But I’m confused about the meat thing, I learned the reason why we need meat is because just about all the plant we consume don’t have all the twenty amino acids which we need to make proteins. So wouldn’t it bad to not consume meat? verses consuming meats in moderation..?

  4. Jacqueline

    Oh my word! I started weight watchers 3 weeks ago and started eating healthy. Today I feel fluish and stuffy. I didn’t know why I was feeling so tired all the time even though I had enough rest at night time. This article really opened my eyes to a whole new world of possibilities!!!!

  5. Carissa

    This is amazing info. This is unbelievably encouraging. Thank you so much!

  6. Madison Celaya

    Wow! amazing topic Teri Rose!

  7. Gabrielle Rosson

    I want to thank you for this article/explanation. You are amazing.

      1. Jake B

        Interesting article, actually stumbled across this as I was looking for an answer to why I feel so sick at the moment when I started eating cleaner about a week ago. That being said, any specific answer to that? It’s weird because I don’t have a gallon bladder anymore since 2013 but I can handle hot wings and the like… I’ve been eating healthy choice meals and stoufer meals that are centered on healthy ingredients and protein so I’m filled up, but I ate some today and hours later felt like I was dying *sigh* idk if it’s because I’m not used to healthy options that are spicier than normal? Or if I’m just having a late reaction to the eating change. I’ve also cut soda and sweet drinks out for over a month now, but I feel the soreness and tiredness and nausea that I’ve only felt from doing a three day total food fast before…not sure if that makes sense or if you can offer some insight? It’d be much appreciated!

        1. Teri Rose, MS, LN, OblSB Post author

          Hi, Jake- With gallbladder removal, watching total fat intake per meal is important (due to the change in bile secretion needed to digest fats). Rather than the spice level, the amount of fat in the various meals might be different. Feelings of nausea would be common with a meal too high in fat (what is “too high” varies by individual; its always a good idea to check in with your doctors if these symptoms persist). As for persisting with the cleaner eating, as mentioned in the article and other comments here, in my opinion, it is always worth the persistence. And I can’t emphasize consistency enough either. Our bodies love consistent change, even if that is only one or two things at a time. Thank you for sharing your question.

  8. Miss

    I’m in my 30’s and have been eating really healthy for the past 5 years. I feel like I look and feel more tired and sick. I am lethargic and just generally feel unwell. It has made me so depressed.

    When I used to eat all kinds of food, including “junk”, I looked younger than my age, felt better and I had more energy. I didn’t feel depressed.

    Also, I tried eating junk foods last year and I felt better again, less sick, less tired, less depressed.

    I only drink water, no soda or coffee, etc. I eat fruits, veggies, quinoa, lean protein, seafood, leafy greens and fermented foods. Yet, I feel so physically unwell even though doctors can’t pinpoint the cause for the unbearable exhaustion and unwell feeling.

    Should I go back to eating junk in moderate amounts? I can’t take this feeling much longer.

    1. Teri Rose, MS, LN, OblSB Post author

      Hi, What you are experiencing would take me in the same direction that I outlined in my response to Carlton below. My starting point if I was working with you would be to do a thorough intake to see how/if your meals are balanced, do they include enough denser carbohydrate to provide sufficient amounts of naturally occurring sugar; I’d explore what your definition of ‘junk’ is and if total caffeine elimination is necessary for you. We’d look at activity and stress management (as I mention below, ‘junkier’ foods can often be our main source of ‘fun’ and we feel the void when they aren’t there if we don’t have a replacement).

      And as importantly, we would look at total food patterns to see where those foods you miss might still have a place. There are higher-quality chips and desserts (made from high-quality ingredients, modest amount of added sugar, and are higher fiber) that don’t need to be eliminated from a healthy lifestyle. The most important consideration is how much of these foods are right for you so that you still make progress towards or maintain your health goals.

      Which brings us exactly back to the question you asked. Most likely, yes, you can enjoy more indulgent foods modestly as long as they are made from high-quality ingredients (and are portioned and other lifestyle factors around stress management are addressed).

      Healthy lifestyles aren’t at all about all-or-nothing mentality. Rather, breaking this mentality is when we can start consistently making the lifestyle choices we want, long-term. This is where I start individuals in my programs: first, provide structured education on what balanced and ‘healthy’ really means, and second) start breaking the mentality that you have to be ‘perfect’ to be healthy; that you have to start over if you aren’t.

      I hope this response helps, and I hope your experience changes soon. If I can be a resource in any way, please just let me know.

  9. nichole

    I started whole30 about 2 weeks or so ago. I’m 16 and i saw how bad we all ate and decided it was time for a change. So I’ve been active and working out the first week and it was fine. Then the second week came around. And i almost had to call off work twice. I felt like I was gonna throw up and i had diarrhea about 2-3 times a day. Here we are 8 days later and although I have kicked the , nauseous feeling, the sickness still is there (i wont go into detail again lol sorry to all the readers with a weak stomach but its how i feel?) but anyway, is this ever gonna stop? School starts up tomorrow and I’m really hoping I don’t feel lousy. I’m not tired at all i just feel sick. What should I do?

    1. Teri Rose, MS, LN, OblSB Post author

      First thing to do: not give up on your healthy changes! We need as many teenage models for healthy change as possible. Second is to stay patient. It is also possible that you came across a virus or bacteria that is making you feel sick, unrelated to your changes. If your diarrhea persists for more than 2-3 days, be sure to see your doctor to get to the bottom of it and make sure you aren’t at risk for dehydration. I do hope you start to feel better so that you can be excited to start a new school year!

    2. Alissa

      Take a moment to compare what you eat now and what you ate before, sometimes making a huge change in your diet causes all the symptoms you are experiencing. Adjust your diet and allow yourself to eat more than just salads and fruits. Stretch to healthily made meats, and don’t restrict yourself completely from things you have heard are unhealthy. Oils and meat fat are crucial to survive. Make sure you transition smoothly into a healthier diet, don’t force it on your body to adjust.

      Hope this helps

  10. Katherine

    I started clean eating five days ago and boy am I tired. I take care of my mother and granddaughter and need energy. I was starting to feel so bad and unable to sleep so I went all organic, drink one gallon of water/day. I pray the level of tiredness lifts. I have a lot on my plate with my family. I do have a thyroid problem but it’s under control with medication. I also walk daily for one hr. One thing that has not changed for me yet is my sleep and I would like to know if I should cont. with my sleep aid. I think this could be contributing to my level of tiredness.

    1. Teri Rose, MS, LN, OblSB Post author

      Hi Katherine- Sleep can be difficult and most often has its own culprits interfering with it (stress being a big one). Without knowing your doctor’s recommendations or reviewing your health history and completing a diet/lifestyle assessment, I’m not able to make a recommendation on your sleep aid. I can encourage you to stick with whole food dietary changes and to continue with your activity (which is significant in helping reduce stress hormones in your body – which will help with sleep). And if you are able, I would also encourage you to find a health care professional in your area to talk with if sleep doesn’t start to improve. They could find seemingly small changes to make that could have significant benefit. Thank you for sharing your comments!

  11. Carlton

    I’ve spent a few years now changing things such as diet, stressors and other things in my life. I *should* by all means feel A LOT better, but it’s not happening.

    7 months ago I stopped drinking soda 100% and do not feel any different.

    I would like to believe that it can be done and maybe some people are doing it, but it’s not working for me. People say “you just need more time”. After almost 7 years of positive changes, how much more time is needed?

    1. Teri Rose, MS, LN, OblSB Post author

      Carlton, thank you for sharing this. You touch on such an important aspect regarding the question of how do we really know when we have done enough things that *should* make us physically healthy? That point at which our blood work looks great, our doctors tell us we are a vision of health, but we don’t *feel* it.

      Professionally, this leads me in three directions:

      1) For individuals stuck here I always like to review a ‘lifestyle’ journal and medical history to see if we can uncover any clues or tweaks that could be made to meal timing, meal composition, activity, etc. At times, when people clean up the quality of their food and eliminate chemicals, there could still be an opportunity to make sure those new healthy foods are keeping blood sugar regulated during the day and are providing adequate nutrients for cells to do their jobs, and

      2) Once those boxes are ensured, it raises the possibility that the individual has indeed done *enough* and have actually uncovered a vulnerability in (for example) their brain’s ability to use dopamine or serotonin (two chemicals that influence how we ‘feel’). Most often, they uncover that food, alcohol, and caffeine were used to provide a sense of pleasure, reward, and comfort. Food, soda, alcohol, and caffeine have become our ‘fun’ (for better or worse). And when we take that ‘fun’ away, even though we are now physically healthier, we can also be taking our ability to feel good away right with it. This might make us realize that we lack hobbies we once had, we aren’t doing the things we wanted, or that somehow we just lost our interests and passions. It’s sure easier at night to pour a drink or eat at our favorite restaurant than it is to figure out what we’d rather do instead. This is called having a “reward deficient” environment.

      3) If the individual is still finding pleasure in activities and able to laugh and play but just still doesn’t feel well, and hasn’t gotten that clean bill of health from their doctor, then I recommend they go investigate other possible causes with their doctors. Chemicals (in foods and drink) can mask a lot and once removed the symptoms still present can provide better data to your doctor about underlying causes.

      I hope this at least gives you other thoughts to explore… it is frustrating when our effort doesn’t match the expected results. Again, thank you for sharing.

      1. Carlton


        For the first time in years I am sitting here in tears. Not that I am upset, but simply because your response makes so much sense. Ive worked with some of the worlds greatest people when it comes to helping me overcome physical problems. People such as Kelly Starrett, Dr. Stu Mcgill and Jill Miller – I am in her book “The Roll Model”.

        You wrote: “This might make us realize that we lack hobbies we once had, we aren’t doing the things we wanted, or that somehow we just lost our interests and passions.”.

        Over the past few years I have lost interest and passion in a lot of areas of my life. Constantly thinking about chronic pain or worrying about whats going to happen next can ruin people. I would literally sit around documenting my daily intake of foods, check my blood sugars, blood pressure etc and find myself *on paper* getting better. But the feeling of *better* wasn’t there.

        This all started in 2010 after I had my gall bladder removed. Medicines that i once took with no issues would now cause my body to ache and feel inflamed.

        Jump forward to 2017 and the same symptoms are present.

        Your site has inspired me to push even further and really work on being happy again. When chronic pain hits, my spirit seems lost. I know I can heal myself.

        Thank you for the informative reply.

        1. Teri Rose, MS, LN, OblSB Post author

          And when our spirit is lost, no lab value or pain index will ever *feel* good. The thing that excites me most about the process of making changing is how adaptable our brains can be… they don’t stay stuck like once thought, they do maintain their flexibility throughout life. They just need some nudging to start valuing the things we want again versus overvaluing the things and habits that no longer serve us. Your persistence in the process of healing yourself shows a strong internal sense of control. The brain loves that for making changes and starting to see natural rewards again.

          The brain finds ‘reframing’ experiences very helpful, too, when trying to reignite interests and passions. A simple technique to help with this to try saying “I FEEL like _____ vs. “I AM ____”. A feeling is temporary (even if that ‘temporary’ is hours or days or, sigh, years). Detaching feelings from our core sense of self, of observing them but not identifying with them, is a premise in mindful mediation (which with your experience with pain management has most likely been introduced to you). Mindful mediation actually makes the part of our brain that regulates fear and emotions (the amygdala) shrink while the area responsible for self-regulation thickens.

          Step 1 is for us to make nutrient-rich dietary changes, become more active, and practice stress management (live a therapeutic lifestyle). Step 2 is then for us to use that renewing strength of our bodies to re-explore and find our new ‘fun’. In other words, to play. That is what health is all for.

          Have fun doing that, Carlton. I wish you all of the best success in applying those passions once you are reintroduced to them!

  12. Shannon

    I am a diabetic type 1. I’ve recently changed my diet to avoid taking so much inslun. Is it normal to experience body aches? I feel like I have a fever and my sugar levels have been good.

    1. Teri Rose, MS, LN, OblSB Post author

      Hi Shannon, as you change insulin dosage, I strongly recommend that you keep your doctor updated on all symptoms you experience. It’s great news that your blood sugar levels have stayed level and it sounds like dietary changes are helping keep your dose lower (all wonderful effort). Let your doctor know of your body aches and fever-like symptoms – they have a complete view of your medical chart and are best to confirm if either need further attention. I’m confident they will also be a great source of encouragement as you continue with your changes! The need is still there for the medical community to see the positive results lifestyle changes can have on medication management… and that there are MANY patients willing to make the commitment. Thank you for being that model to them (and for sharing your comments with us)!

  13. Amy

    I finally took the plunge a few weeks ago and met with a nutritionist because I knew I needed help with a better way of eating. I had been feeling so rotten for so long and eliminating any major medical problems, I figured my diet was to blame. I’m on day 8 of a healthier eating plan, but I still feel so tired and have major brain fog. I am still sticking with it but I was hoping to see at least a little change by now ( I have lost weight, but that wasn’t my main motivation for doing this). I am sure everyone is different in when they see results. Also, I figured I have been eating crappy over processed foods for so long, it will take time for my body to recover!

    1. Teri Rose, MS, LN, OblSB Post author

      Hi Amy! You are right, it will take time and that amount of time is so very different for everyone. The ability to stay persistent, when we know we should but it doesn’t feel good to, is worthy of its own post. Stay tuned… that one will be coming since it go so hand in hand to this one about the physiological changes. Until then, do stay persistent. Each day moves you closer to feeling better. And be sure to stay hydrated, moving during the day, and rested at night. Thanks for sharing your comment!

    1. Teri Rose, MS, LN, OblSB Post author

      Hi Adam- At times changing habits will feel that way. Pressing on with healthy changes (like going for a walk or eating a produce-based dinner) at the end of a long day or when faced with external stress isn’t the easier thing to do (at first).

      You raise a very important piece to making long-term change. Defining the purpose, the real reason why, you want to make that change. Defining what “it” is all for. To start this, I recommend everyone take a couple of minutes to fill in the blank for “it” in your comment: “________ is almost not worth it”.

      Here are some examples of how real clients of mine have filled in for “it” in similar statements defining their true reason for health: “Aging well so that I can keep up with my family”, “Reducing my risk of high-cost diabetes”, “Feeling well enough to participate in community events”, “Having enough energy after work to enjoy a favorite hobby”.

      When you put anyone of these into the above statement, I think it will start to reframe your motivation: “Aging well so that I can keep up with my family is almost not worth it.” Sounds different like this, doesn’t it?

      Here is a another blog post where I shared how I define my true reason for committing to healthy choices: https://www.perfectlyproduce.com/making-changes-define-your-true-reason-for-health/

      Even knowing as much as I do about health and nutrition, I am still vulnerable to stress and old habits that don’t serve me well anymore. But I stay committed to making better choices because of what I compromise when I don’t. Because in all honesty, somedays it does feel (almost) too hard. But I do know “it” is always worth it. :)

      Thank you for the comment and contributing to the conversation.

  14. Cheryl

    So five days ago I went from a horrid diet, three cupcakes for breakfast type bad, to eating clean. Plain tuna, cabbage soup, boiled eggs, ect… I have a long history of panic disorder and agoraphovia…. Well the past three days I have felt bad anxiety and my agoraphobia has gotten worse… Is this temporary… I’m pretty freaked out….

    1. Teri Rose, MS, LN, OblSB Post author

      Hi, Cheryl- I recommend that you check in with your doctor and medical team. Whenever changes impair daily functioning, it is important to ensure your doctors are aware so that they can monitor you more closely (and healthy lifestyle changes can even require adjustments be made to medications). A high sugar diet does alter neurotransmitter levels (like serotonin and beta-endorphins) and reducing that sugar will cause a decrease in these same chemicals. How long it will take for you to naturally increase these levels to start alleviating your symptoms depends on so many factors – genetics being one of them. Try staying active (even around the house). Activity is helpful at raising these levels. Your healthy lifestyle changes are supporting you, they just might have also revealed how sugar and other chemicals where temporarily covering bigger issues rather than solving them. I recommend you persist with your changes but do check in with your doctor. And persisting will be hard (some days much harder than others). And training your brain to make these changes new habits will take a commitment to practicing the changes. Be sure to have a support network ready to help. And know that the effort is worth it (really worth it)! Thanks for your note and sharing your experience. :)

  15. Kat Wylie

    Thank you for this article. I’ve changed my lifestyle, progressively, over the last two weeks and in the last couple of days I feel as if a cold is coming on. This article describes, perfectly, what I’m experiencing. It’s good to know that what I’m going through is a good thing and serves as a reminder to keep pushing through the discomfort. Previous attempts at lifestyle changes were stopped short for this exact reason. I’m ready to press on!

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