Keto Flu Survival Guide

Just started on Keto or a similar low-carb diet – and feeling terrible? Constantly fighting tiredness, headaches or muscle cramps? You’ve been hit with Keto flu.

Perhaps you are thinking that Keto isn’t such a good idea after all… Don’t give up on it just yet! There are ways to get through this – and it will definitely be worth it.

You might already know that these unpleasant side effects are not uncommon – especially if you are trying Keto for the first time.

Keto flu – also known as low-carb flu or Atkins flu – is unpleasant but completely normal.

What exactly is Keto flu?

Keto flu occurs when you cut your carb intake down to about 20-30g a day, in order to induce nutritional ketosis. This is stage one of two popular low-carb diets – Keto and Atkins.

Your body is used to running on carbs. It’s been operating this way for decades. Cutting carbs in favour of fat is a huge change for your metabolism. So you don’t switch over instantly. It takes a little bit of time to adjust.

This transition often causes temporary flu-like symptoms. Fatigue is the most common one, but you might also get muscle cramps, headaches, dizziness and mental fog.

Some of these symptoms are markers of sugar withdrawal. Sugar addiction is real and common, so trying to break away can be difficult. Others may be caused by a lack of certain nutrients, for example, electrolyte depletion or insufficient fat intake.

But there are ways you can tackle all of these issues.

Keto flu is not the same as the actual real flu

Keto flu does not include fever or respiratory symptoms like coughing or sneezing.

If you are experiencing any of these, it means that you might have actually caught an infection! Postpone your diet until you are all clear.

How long does Keto flu last?

Keto flu typically lasts around 3-5 days but could drag on for 1-2 weeks for some unfortunate individuals.

Many factors affect the speed and ease of Keto transition.

Some of them are fixed, like your genetics or your level of metabolic resistance. But you can speed up the transition by eating right, taking targeted supplements and staying active.

Here are some simple tips on how to stimulate the onset of ketosis and fight the symptoms of Keto flu.

1. Count your carbs religiously

This is the most obvious and also the most important part of any low-carb diet. And yet, some of us still stumble at this very first step!

Your carb counting must be very accurate. Just a few sneaky extra grams a day could prevent ketosis and keep you trapped in the Keto flu period. And those few grams are actually very easy to miss.

Read our carb-counting guide to avoid common traps and beginner mistakes.

2. Eat lots of fat

Fat is the key to this whole issue.

You must eat lots of it – a lot more than what you used to get on a standard diet.

You are basically replacing carbs with fat as your main source of energy. If you don’t get enough fat, you will feel tired and it will take longer to break into ketosis.

Aim to get at least 65% of your total calories from fat. Some people go as high as 80%.

This is actually not easy. It requires a conscious effort. We have all been conditioned to avoid fat for decades.

The medical establishment and the media are now (slowly) admitting they were wrong about dietary fat. But we are still stuck with the ingrained habit of fat-avoidance. Reverse this conditioning and embrace fat.

  • Eat fatty meats (for example, rib-eye steak, pork belly, lamb chops, bacon), poultry with skin, fatty fish such as salmon and sardines
  • Add butter and cold-pressed oils to your cooked vegetables and salads
  • Use full-fat cream (or even butter!) in your tea and coffee
  • Snack on cheese, avocados, macadamia and brazil nuts
  • Use home-made high-fat sauces and condiments like Bearnaise

Related post: 30 Ways to Eat More Fat

3. Watch out for too much protein

Too much protein can interfere with your transition. Your body has a sneaky way of converting excess protein into carbs. You definitely don’t want that! Because it could slow down your switch to ketosis.

Replace the carbs you are not eating with fat, rather than with protein.

Once you are fully Keto-adapted, you can review your macros. You may need to increase your protein. But while you are transitioning, always err on the side of “More fat!”

Use a Keto macro calculator to figure out exactly how much protein and fat you need in grams per day on your Keto diet.

4. Track your nutrition

Having said all this, it is definitely a good idea to track all of your nutrition by keeping a food diary. So that you know exactly how many grams of carbs, protein and fat you are getting.

Use a food tracking app, a web-based service, or just a plain pen and paper.

Be honest with yourself, track all your food accurately and check your macros throughout the day to make sure you are on track.

If you don’t track your food, it’s very easy to mess up your macros and get stuck in the Keto flu period for ages.

You won’t have to do this laborious tracking forever – only until you are fully familiar with the diet. After a while, counting carbs will become easy and you will likely remember the counts for all your favourite foods on top of your head.

5. Avoid sweeteners and sugar-free treats

Sugar-free is a pretty big market now. You can buy zero-carb sweeteners and sugar-free treats easily. But there are multiple potential problems.

Some of these products are actually not as low in carbs as they claim to be. But even genuine sugar-free low-carb products can delay ketosis.

You are trying to break away from the addiction to sugar and sweets. Your body needs to get used to burning fat instead of carbs.

Consuming sweet-tasting treats will just confuse your system and may cause strong cravings. Some people even experience a placebo-like effect on their blood sugar simply as a result of the sweet taste.

Once you have made the switch and become adapted to low-carb, you could reconsider these products.

6. Move – even if you are tired

When you are in the middle of Keto flu, the last thing you feel like doing is moving. However, it is important to do something.

Your energy levels will be lower than usual, so don’t expect to be able to do your normal amount of exercise. But don’t be tempted into just sitting or lying down all day either. Your body will try to conserve energy. But the only way to encourage it to tap into your fat reserves is to spend energy.

If you can’t do anything else, at least drag yourself out and go for a walk. It doesn’t have to be fast or energetic. Just walk.

7. Replenish electrolytes

Drinking enough water is crucial on Keto. Most people get thirsty when following this diet so drinking more just happens naturally.

Glycogen binds water in your body tissues. So as your glycogen stores deplete, key electrolytes – sodium, magnesium, and potassium – get washed out of your body.

Electrolyte deficiency causes tiredness, muscle cramps and headaches. This is the main reason we feel so rubbish during Keto flu.

The easiest way to replenish electrolytes is to take supplements. Try also drinking mineral water instead of plain water. Simply adding more salt (sodium) to your food also helps.

Another popular way to replenish electrolytes on Keto is by drinking bone broth.

8. Take targeted supplements to speed up ketosis

Certain dietary supplements can also help to speed up your transition to ketosis and reduce the symptoms of Keto flu.

Exogenous ketones instantly elevate your ketone levels. They induce “artificial” state of ketosis, creating an instant energy boost. If you are already on the brink of switching over to ketosis naturally, exogenous ketones can give you that last crucial push in the right direction. The most common format is BHB salts – providing electrolytes and exogenous ketones in a single product. Please note that “Raspberry Ketones” are NOT the same, despite the name – they are a bit of a scam that does precisely nothing for your ketosis.

Co-Enzyme Q10 and L-Carnitine were recommended by Dr Atkins to speed up ketosis and improve fat-burning metabolism

Key minerals – potassium and magnesium to replenish your electrolyte levels and reduce the symptoms of Keto flu

High-quality Keto multivitamins to bridge any potential nutritional gaps and boost energy-yielding metabolism

Do you have any Keto flu tips to share?

Please share your tips in the Comments section!

Keto flu - 8 ways to cope

96 thoughts on “Keto Flu Survival Guide”

  1. Pingback: BHB Salts - Waste Of Money, Or Not?

  2. Hi, this is some good advice here. I have been researching loads over the past 3 weeks. My story is that I’ve been suffering from Ulcerative Colitis for nearly 3 years now and have had only 2 short periods of remission. My meds are currently not working so I have taken the plunge with keto after first starting out with SCD and then a high carb vegan/fruit diet. (which worked to some extent) I have opted for a vegan keto diet which is really hard but has been working, I’m 2 weeks in and have lost 10lbs have clarity of mind and tons of energy throughout the day, especially after a bulletproof coffee. I used to be a bodybuilder and ate a ton of protein, but since having Colitis I cant stomach meat or much dairy or whey protein shakes, so have been living of plant based protein and tofu. I still train 3 x a week now and when I do I get ravishingly hungry especially after 6pm. I think I still need to increase the fat as I do crave carbs late at night, it is hard to get my head around how much fat I may need to eat and what are the long term effects of eating this way. As it stands my symptoms are quite manageable going from 20 bowel movements a day to averaging 4. I have read many reports that Keto can reverse the effects of colitis and chrone’s disease… here’s hoping.

    1. Hi ! I’ve been doing keto on my own for 2 weeks now. Results are not as good as people say, so I might have done something wrong since I had no strict plan. That’s why i’m here in fact 😉 The thing is that my goal is, of course, to lose some fat, but ultimately to build muscle mass to compete in bodybuilding.This is why i was wondering if, in your opinion, your keto approach were still a good way to go !
      thank you !

  3. Hey Carbophobic,
    Do I need to worry about too much sodium. Most foods that fall within the Keto diet are very high in sodium. I know the whole benefits vs. dangers of sodium, particularly salt, is a controversial issue now, so I’m not trying to open a can of worms.

    1. Hi Brian, this is an interesting question.
      I would disagree that most Keto foods are high in sodium. A healthy Keto diet should be based on natural whole foods like animal proteins, healthy oils, and low-carb vegetables. None of these foods are high in sodium in their natural state. Typically, foods that are highest in sodium are processed foods – extra salt is added as a preservative and taste enhancer.
      Secondly, ketosis affects the rate of electrolytes depletion in our bodies. There are significant differences between a Keto dieter and someone who mainly eats highly-processed, carbohydrate-rich foods (as many people in the West do). Here’s a good article on this subject:
      So overall, if your Keto diet is based on natural foods and you are in good health overall, sodium shouldn’t be a problem. Depending on your diet’s make-up, you may even need to supplement it.
      Having said all that, if you have high blood pressure or any other cardio health issues, definitely discuss this issue with your doctor or another qualified health professional – ideally, one who is also knowledgeable about low-carb and Keto.
      Best of luck!

        1. Hi Farha, congratulations on starting Keto! Full-cream in tea is definitely a good idea – it’s much lower in carbs than milk. Regarding potassium and magnesium, you only need to take them if you get symptoms of Keto flu (tiredness, leg cramps, headache etc). Some people just sail through without any such problems – it depends on many individual factors. So don’t worry about supplements unless you feel like you need them. Good luck!

  4. I have asthma, and all the fats you mentioned aggravate it.
    In fact, all I can really eat that doesn’t aggravate my asthma is lean meats and vegetables.
    What should I do?

    1. Hi John,
      We can’t give medical-related advice like that over the internet. I have a few thoughts but you really should discuss this issue with your doctor or a qualified dietitian.
      Have you tried highly-refined natural fats like ghee (clarified butter) or MCT oil They are pretty much just very pure fat, so might happen to be free of whatever it is that triggers your asthma.
      Alternatively, if all fats are definitely a problem, perhaps you could try Dukan diet instead of Keto?
      Dukan is both low-carb and low-fat, so it’s possible to follow it eating just lean meats and veggies.
      Best of luck!

    2. You give some stupid advice. In order to get over the carb flu, one simply needs to eat more sodium and potassium and MAYBE magnesium. Maybe. You wrote an entire article with wrong information. WOW.
      Add more sodium to your food or drink some water with some Lite Salt added. That is ALL you need to do to alleviate the keto flu.
      Oh, and by the way, telling someone to not reach their protein macro is INSANELY stupid.

      1. Thank you for sharing your opinion, Brian.
        It would be more polite not to call me stupid – but oh well, never mind – I will respond despite your rudeness.
        There is a great deal of variance in supplement needs. Each individual may need different amounts of sodium, magnesium and potassium – depending on the exact make-up of their diet, type of water they drink, and a whole range of other factors. Whatever your personal experience is, you can’t make such sweeping generalizations about everyone else.
        Secondly, even if you disagree regarding magnesium, the “entire article” wasn’t just about electrolytes. Other points mentioned (sufficient fat intake, avoiding hidden carbs, avoiding sweeteners etc) can also affect low-carb flu symptoms. If you personally haven’t experienced that, there are many others who have.
        Finally, not sure where you got the point about “not reaching protein macro”. I emphasized not eating too much protein during the transition period only (usually 3-5 days total). Plus, I actually recommended using a macro calculator to set the right levels for all macros, including protein.

        1. An extremely professional way to deal with a rude, uninformed person. You are right. Everyone is different, and may respond differently when starting a low carb eating plan. . Your article touches on many ways to deal with “low carb flu”, and hopefully will help many get through it.
          This Brian saying to just have more salt is not just a generalization, but not a safe way for many of us to deal with the possible issues that come with Induction.

      2. You really do not need to be a dongbag! If you disagree with a person that is fine but calling them stupid just shows us how small your brain is. People are not an exact science what works for person A; may not for person B.

    1. Hi Michael, thanks! Good tips about salting foods and drinking broth!
      Regarding electrolyte supplements, indeed, there are quite a few new products on the market that bundle essential electrolytes into a single product. I think they are great. Powder form is probably better than capsules or tablets so you can easily tweak dosage to suit your individual requirement.
      My only concern is that a bundle doesn’t necessarily work for everyone. We all have different levels of supplementation we need, depending on many factors. For example, someone might get lots of potassium with food but not enough magnesium. So they would need to supplement magnesium and other electrolytes, but not potassium. In which case they’d be better off with separate products for each mineral.
      Best of luck with your diet!

  5. good read, i just started mine a few days ago, but not serious with the apps. after reading the article and comment section.. ill download a phone app to help track my progress….
    i just feel freakin hungry all the time lol. i cant say i have soreness or anything cuz i just started to workout at the gym (with me going to the gym WITHOUT a diet, i would be feeling sore now too anyways lol… so i cant say its the flu on this post is about)…
    my worry is im not doing the diet correctly at all.. maybe to many carbs, not enough protein and good fats…
    it be nice if i had material i could buy that already has weekly/monthly meal plans… to make it easier for me to buy food… cuz im freakin clueless.. i udnerstand chicken, salamin, etc…. but i want a good meal! not just cook some grilled chicken, take a sip of olive oil, etc etc… i want a good meal meal… but i aint got nothing but salads with dressing low in carbs/sugar like the lite ceasor salad olive garden dressing.
    any suggestions for food intake websites for sources… not for calculating your levels… but actual apps for our atkins diet that is cheap or free and good, which tells you what you should have today for breakfast, lunch, and dinner, and also tells you the meals for the next week so you can start shopping for the ingredients??

    1. Go to the diet Dr. Website for two week keto challenge. It gives you a shopping list as well as meal plans…..good luck
      Also warm broth from a cube exponentially helps curb hunger between meals.

    2. Hi Bruce, thanks for sharing your experience. Hitting the right macros is crucial so using meal plans is indeed a great idea.
      Here are a few I can recommend:
      Keto Weekly Plans by Healthful Pursuit – not free but definitely good value – and you can try out a sample plan for free:
      30-day Ketogenic meal plan by – donation-based, you can choose the amount:
      Free 14-day Keto diet plan by Diet Doctor, with recipes:
      There is also the official Atkins app by Atkins Nutritionals, which is free – but I haven’t used it myself, so not sure if it would fit your needs:

    3. Do you have the Atkins book? The diet plan book shows meal plans and recipes, plus there are great Atkins recipe books, as well as sites with ideas.
      Good luck!

    4. There is a website called by Tasteaholics.
      They do all the macros for you for each individual meal, give you a complete grocery list and weekly meal plan. Every Wednesday they email you a new meal plan so you’re always switching it up. If you need to adjust the macros you can do so by just adding or substituting some of the ingredients.
      It’s what I use and I absolutely love it.

  6. Hi I am in week five fatigued all the time ! Taking Swiss women’s vut using app as of yesterday to try to understand macro think I have it 1/2 with fat being 2 and carb aiming for 20
    Weight only going down slowly can I still take extra pot and mag with my Swiss vitamin I can hardly function getting sick of it . Justvwondered if u have any ideas I am about 6 pound down

    1. Hi
      I checked out Swisse Women Multi. Is it this one –
      If yes, then you could safely take additional magnesium and potassium supplement – that formulation only contains a very small amount of magnesium.
      Alternatively, you could try a multivitamin formula designed for low-carb dieters, like this one:
      One other point to note is that macros are really important – in fact, the most important point. If you are not 100% sure you are getting it right, start tracking your food precisely with an app or an online food tracker. You may be really surprised! If you are still fatigued at week 5, perhaps you are not getting enough fat, or eating more carbs than you think.
      Best of luck!

      1. Hello thank you very much yes I think not enough carb I have started tracking my carb is usually 20-30 trying to get it down. Thank you so much for your help . Have a great week !

  7. Is the recommended dosage of daily carbs net carbs? Because I know Atkins etc was a big thing on net carbs, not just total carbs.

    1. Net carbs vs total carbs count is important if you are based in the USA. Their food labels show total carbs – both digestible and non-digestible. That’s why Americans need to do the extra step of subtracting fibre from total carbs, to arrive at the “net carbs” figure.
      In Europe, Australia and Oceania, food labelling regulations are different. Food labels already show only digestible “net carbs” – there is no need to subtract fibre again.
      I agree this issue is really confusing – I wrote a detailed post about this a while back:
      If you are in Australia (OZbloke – Aussie Bloke? Apologies if I got that wrong…), here’s an article from Atkins Australia about the same issue:

    2. I am not only feeling extremely fatigued. I am severely nauses to the point of the thought of food makes me want to throw up. And moving just makes it worse. Going on day 5 not feeling any better. No fever or chills or cough. Do have cramping diarrhea as well. What else can help. Caffinee, sugar withdrawals also have stopped taking this week as well unisom and Excedrin pm, large doses of both. Could this be adding to my suffering as well? Detox overload. My boyfriend is having a hard time believing this is real. Please jelp me help him understand that it is real and I am not able to just push through right now. I really feel sick. Help!

      1. Hi Shell,
        What you describe doesn’t sound like a typical Keto flu.
        It could be that your symptoms are worse due to withdrawal from caffeine, plus also cutting out your sleeping pills and migraine meds all at the same time. That’s a lot for your body to tackle all at once!
        I strongly recommend discussing the symptoms with your doctor or another health professional ASAP.
        They will be able to recommend the optimal strategy for diet/detox for you, based on your symptoms and your health history.
        Best of luck, and I hope your doctor will provide more precise recommendations to make the diet work for you.

  8. Hello Carbophobic 🙂
    I just wanted to get a rundown on my diet which i have been eating for 3 days now, to see if you could flag an area i’m going wrong, rather than being on this meal plan for 3 weeks and realising it wasn’t an ideal breakdown for reaching ketosis.
    3x decafe coffees with 2tblspoons dbl cream (6 in total for the day)
    1x boiled egg with salt/pepper
    1x red bell pepper
    1x can mackeral in brine/water
    with 2 tblspoons full fat mayo & mustard
    handful broccoli
    with 2 tblspoon mayo & hot sauce
    50g rasperries
    4 tblspoons full fat greek yoghurt
    8 almonds
    4/6 oz cheddar cheese
    green smoothie:
    1 avocado
    1 strip/handful of cucumber
    1 large knob of ginger
    handful of coriander
    small handful spinach
    Just by having a quick look, does this ratio seem balanced?
    I’m 5’4 / 41 yrs with just excess fat around my midriff, and a bit all over to lose.
    I’m on my 3rd day and feeling very sluggish, but that is all.
    I do light running/lunges/sit-ups but have only been once since starting but the next morning i did get that metallic taste in my mouth which i know to be from ketosis.
    I haven’t had that taste again this morning.
    Any advice would be great!
    Many thanks

    1. Hi Alexandra
      In the beginning of your diet, it’s important to be very precise with your carb counts. Otherwise, it is easy to go over your limit without realising. I definitely recommend weighing all your food on the kitchen scales – at least for the first 1-2 weeks, until you get the feel for correct quantities.
      I did a quick approximate calculation (but not precise, as you haven’t listed the exact weight of your food), and I think you may be going over your carb limit a little bit. Remember that some high-fat foods – like double cream, Greek yoghurt, avocado, almonds – still have some carbs in them, which quickly adds up.
      But once again, the only way to tell for sure would be to weigh everything and log it using an app or an online tool.
      Best of luck!

      1. Ok thanks Carbophobic, your thoughts are helpful, I will start using a scales as you say.
        I appreciate you taking the time to answer me.
        Many thanks 🙂

        1. Look for the app “cronometer “.
          It’s super easy to use even on the run.
          Takes the guess work out!

    2. I cannot stress enough how important the new Atkins diet book was for me. I lost 60 lbs in about 7 months, and it’s still off 8 years later. I am now 61, so even in your later years, it is possible to do this.
      The book shows you how to eat during each stage. I’m not an expert but it seems you are not eating enough salad greens and should not be eating nuts in the beginning. For me, nuts slowed the weight loss.
      Anyway, get the book if you can.

      1. Thanks for sharing your tips, LS! I agree about the Atkins book – it’s extremely useful. And thank you for sharing your fantastic weight loss results – inspiring!

  9. I have started a keto diet a week ago .i am having a terrible headache and i cant even sleep.i feel like crap.Otherwise i was doing fine all along.

    1. Hi Inno, headache is very common during Keto flu. Have you tried supplementing electrolytes (magnesium, potassium), as suggested in the article? Hope you feel better soon.

    1. I don’t think it’s a common symptom but if you are prone to anxiety attacks, then perhaps a sudden change in diet may have triggered it?
      I would definitely recommend discussing this with your doctor or therapist. Your mental health and wellbeing are more important than weight loss! Best of luck.

      1. Anxiety is not as common as other symptoms. Have you had any problems with anxiety before starting the diet?
        If it’s really severe, I definitely recommend discussing with a doctor.
        Hope it gets better soon!

  10. My description for keto flu is like having a bad hangover without the booze. I treated my headache and queasiness with Alka Seltzer Original. For the heartburn, famotidine. I drank lots of tea including ginger tea, nibbled on 1/4 of a grapefruit, ate olives and pickles. I like to mix up 2 raw organic eggs with a bit of soy sauce and add 2 tbsp of evoo. It’s not gross and the soy sauce adds a nice flavor. Hot sauce and pepper can be added. Couldn’t find much help for the fatigue and brain fog. I essentially treated my keto flu like a hangover. Mornings were the worst but with my treatments, by about noon I started feeling mostly human. I’m glad I’m self-employed. There was no way I could drive to a job the way I felt when I got up. Head throbbing, dizzy, heart pounding, exhausted after 8 hours of sleep, hands shaking, queasiness, GERD, extremely thirsty, hyperactive digestive tract. Being vertical was not pleasant…I needed to be flat. Essentially couldn’t function. Tried to take a nap but I couldn’t fall asleep.
    Previously, I didn’t eat sugar at all, very limited carbs, and rarely processed foods. I’m a devoted food label reader. I’ve been on a super low carb diet in the past and never had a problem. So I’m surprised with the keto hangover. I woke up with the symptoms on the 3rd day. It lasted only 3 days, though but they were miserable days.
    I don’t need to lose weight. I’m 5’6″, 110 lbs. I’m doing this for my liver. I have the beginnings of NAFLD (non-alcoholic fatty liver disease). My doctor thinks it’s caused by one of one of the drugs I take for arthritis (well documented) and wants me to discontinue it. The drug raised my serum triglycerides also which leads to NAFLD. In the mean time I need to heal my liver.
    I think it should be called keto hangover. For me that’s exactly what it feels like. I haven’t had many in my adult life but I sure remember my younger days!

    1. Lol, yes, Keto hangover would be a better term for it 🙂
      Best of luck with your diet – I hope you can avoid it in the future.

  11. Try miso. It contains electrolytes and is very healthy Add some sesame or coconut oil for fat and some seaweed or green leafy veggies and tofu.
    Nutrition Facts (2 tbsp of miso paste)
    Calories 80 (333 kJ)
    Calories from fat 22
    % Daily Value 1
    Total Fat 2.4g 4%
    Sat. Fat 0.5g 2%
    Cholesterol 0mg 0%
    Sodium 1491mg 62%
    Total Carbs. 10.6g 4%
    Dietary Fiber 2.2g 9%
    Sugars 2.5g
    Protein 4.7g
    Calcium 22.8mg
    Potassium 84mg
    Nutrition Facts (1 oz firm tofu)
    Calories 41 (172 kJ)
    Calories from fat 22
    % Daily Value 1
    Total Fat 2.5g 4%
    Sat. Fat 0.4g 2%
    Cholesterol 0mg 0%
    Sodium 4mg < 1%
    Total Carbs. 1.2g < 1%
    Dietary Fiber 0.7g 3%
    Protein 4.5g
    Calcium 193.6mg
    Potassium 67.2mg

  12. Edith D. Thurman

    Ok I’ve got a question. I’ve been doing low carb under 20-25 grams a day since the end of December. Now as of Feb 20 I’ve felt like crap. Queasy to my stomach, headache that won’t quit, muscle cramps all that nice crap. I drink close to a gallon of water a day, I’m taking vitamins and supplements including magnesium, sodium, amino acids, zinc, everything I can yet I can’t figure out what happened! I did not get the Keto flu, I had two days where my shoulder sockets hurt like crazy, but that was it. I’ve done my research almost finished with Volek & Phinny’s “art and science of low carbohydrate diet” yet now after two months I’m feeling horrible. What am I missing? I’m eating 80-15-5%

      1. Perhaps some of us take longer to become keto-adapted. I already have M.E/CFS…now feel shattered. I think the liver is also doing a detox (sure feels like it) (itchy skin) and working hard to make ketones at the same time. Good luck. I’m persevering. 🙂

        1. Keto strips can be misleading so be careful. They can be thrown off by dehydration, too much water, and workouts.

          1. Thanks for adding this point, you are absolutely right. A single reading might be inaccurate, so it’s a good idea to try several times at different points during your day.

    1. Hi Edith,
      Apologies for not replying sooner.
      It’s obviously quite hard to figure out exactly what’s gone wrong based on a brief description online. But if I had to make a guess, I would say it sounds like you might have got knocked out of ketosis.
      Do you track your ketone levels? It’s quite easy to do with ketosticks:
      If you are not in ketosis, then you need to re-evaluate your macros. Do you check labels and track all your food, all the time? Have you recently added any new foods to your diet (especially sugar-free treats and sweeteners)? Maybe some hidden carbs are creeping in where you don’t expect them (for example, in OTC medicines or processed meats)?

  13. Pingback: The top ten things I learned on a low-carb diet | Fat Bastard Rides His Bike … Again

    1. Hi Jennifer,
      Some people experience muscle pain and muscle cramps during Keto flu. This is usually due to the lack of electrolytes in your system. Try supplementing with magnesium and potassium.
      Sodium is also important – just try adding more salt to your food, or make a bone broth.
      If these supplements don’t help, and you are still in pain, then I would pause the diet and go see a doctor.

  14. “Eat Fat rather than Protein” – wow, that confuses me I’m afraid. Isn’t most every protein full of fat, other than say fish? Dairy and red meat come to mind. I’d have to research around about oils, but assume they fall into the fat rather than protein.
    Recommendations? Thanks, btw, for your flu explanation – I had it big time last night….

    1. Sorry if it’s confusing Anne.
      Most animal protein foods, like meat and poultry, do contain some fat. But they are not necessarily “full of fat”. For example, chicken breasts contain only about 3g of fat per 100g. Even really fatty cuts of read meat, like rib eye steaks, have about the same amounts of both – about 25g of both fat and protein per 100g.
      The best thing to do is to use a macro calculator to figure out exactly how many grams of fat and protein you need every day, and then use a food tracking app to log your food. So that you know exactly whether you getting the right amounts of fat, protein and carbs.
      This sounds like a lot of work, but you don’t have to do it forever. Just until you get used to Keto. You will also gradually learn nutritional values of all your favourite foods.
      Some people manage to get into ketosis easily without tracking their food, which is great. But if you are having problems, like unusually long Keto flu, then tracking is the first step to make sure all your macros are definitely correct.
      Best of luck with Keto!

  15. I’ve fully felt this when I started the paleo diet. I found that drinking walnut and olive oils right off the spoon really helped take the edge off.
    Even though some people might think that’s strange, those oils are packed with poly and mono unsaturated fats which your body just loves and can use for extra energy.
    And DEFINITELY drink as much water as possible. The brightens everything up.
    Thanks for this 🙂

  16. There are many females that practice a successful ketogenic diet that will attest to not going below 50gr of carbs daily. Most, although not all, females need carbs to maintain normal hormonal health, especially thyroid. Check out what Stephanie has to say on Robb Wolf’s site:
    Leanne Vogel of, specifically helps women reach peak adaptation w a higher carbohydrate ratio plan.
    As for me, I have struggled with a keto lifestyle for way too long… for some people, fat adaptation is an easy process and takes only a few days of VLC/HF eating. For others it can take several months. I tried a ketogenic diet at least 3 times in the last year and each time I was very determined and committed to making this work. The last time I quit after 6 weeks because I was so miserable. I was suffering from depression, brain fog, horrific (jump out of bed in the middle of the night) muscle cramping, hair loss and lack of sleep. I was so exhausted, I could hardly function on a daily basis. Oh… unlike many others, I had very little weight loss. I felt so bad following this diet that for me, it just wasn’t worth pursuing any further. I also reached out to several Keto gurus on websites for help and advise. I tried various supplements, drank more water, added pink mineral salt, extra potassium, extra magnesium, methylated B12, D3, 5HTP, and the list of what was suggested and what I tried went on, to no avail.
    Perhaps I needed to ease into it slower… or maybe I just needed to accept that it’s simply not a good diet for me. I honestly don’t know what the problem was, but I do know this: While it may be an optimal diet for some, it was unsustainable for me (by the typical keto standards of extremely low-carb) I was committed for 6 long weeks to see what would happen, but this experiment only managed to make me feel like a failure.
    Thanks for reading this. Any and all comments are appreciated.

    1. Hi Donna, you are absolutely right. There is no such thing as a magic-bullet diet that works for everyone, and Keto is no exception. If you tried all the recommended “troubleshooting” solutions like supplements, and nothing worked, then of course the sensible thing to do was to stop the diet, and look for another way. Thank you for sharing your experience here! I hope you found another weight loss method that works better for you.

  17. I have just been a week in this new lifestyle, my blood pressure was high and now am tired, no appetite even when I try to drink water I can’t, I just take a sip that’s it. Am I on carb flu,?

    1. It sounds like it could be low-carb flu. No appetite is normal, but you need to try and drink more. Tiredness should pass soon – see the tips in the article above on how to speed up this process. If you are on any medications for your blood pressure, or if you have any other medical conditions, I recommend discussing the diet with your doctor, if you haven’t already done so.

  18. I’ve tried low carb multiple times. I can do it about a week and then I start to freak out. I usually do no carb, not low carb. Do you think the no carb is too extreme and the reason why I can usually last just one week?

    1. Hi Buddy, going zero carb is definitely not a good idea. All popular ketogenic diets include a small amount of carbs – usually 20g a day. It is not recommended to go below that amount.
      The main reason is providing enough glucose for your brain. Unlike other parts of your body, your brain cannot get everything it needs from fat and protein alone. So it needs that little bit of carbs to function properly.
      Secondly, it’s very hard to get all the vitamins you need without eating at least some vegetables. So ideally, you should spend your 20g allowance on the most vitamin-rich low-carb foods.
      Finally, supporting your low-carb diet with multivitamins (and possibly other supplements to target specific problems like sugar cravings) can make a huge difference. Check out Nutri-Align and KetoLabs – both specialise in supplements for low-carb dieters.

      1. wrt needing carbs for brain etc. The brain actually needs about 100g a day. However we can create 100% of the required carbohydrate from fats through gluconeogenesis. However your point about vitamins and low car vegetables stands.
        Above it mentions taking B-Vitamins which makes no sense because the meats in a ketogenic diet should be providing tons of b vitamins .

        1. Hi
          Thanks for your comment! Excellent points.
          Regarding carbs for brain – I agree that the total requirement is usually cited between 100-130g of glucose a day, and that ketones can fulfil some of that. However, my understanding is that it can only cover 50-75% of the requirement – not 100%.
          Beyond that, as part of starvation response mechanism, the brain would then start to break down proteins in the body (i.e. muscle) which is obviously not desirable. Hence the recommendation to get the minimum 20g of carbs.
          Starvation response in the brain:

          Acute nutritional ketosis: implications for exercise performance and metabolism

          Regarding B vitamins – yes, you would get lots from red meat. But the purpose of supplementation is not just to prevent deficiency.
          Extra-strong dosages of some B vitamins, and vitamin C, have known therapeutic effects. One benefit is the reduction of tiredness and fatigue. In Europe, this is a government-approved health claim which can be used officially on supplements:

          1. I think you may have missed his point. As long as your liver is functioning properly and well it can generate 100% of the carbs that your brain needs from fat.
            This is in addition to the Ketone bodies that the liver produces which the brain can use for part of its energy needs. You are correct that the brain cannot use exclusively ketones, the brain still need some carbs. However those carbs do not need to come from your diet, they can be made by the liver.
            Personally, I think it is a good idea to have carbs in your diet in the early stages of a keto diet, because the liver may struggle to produced the carbs that are needed. Most people’s livers are just not adapted to that role initially.

          2. Thanks John.
            The discussion is getting rather technical now, which is beyond the scope of this post.
            My point was simply that it’s better to include a small amount of carbs on Keto – up to 20g – rather than go zero-carb.
            Everyone seems to agree with this standard recommendation – including yourself and user Somebody from the previous comment – even though your reasons for agreeing might be different from mine.

    1. Hi Loretta, in order to get into ketosis, you need to keep within the following macronutrient ranges:
      Carbs: 5-7% of calories (between 15-40g of net carbs a day)
      Protein: 15-25% of calories
      Fat: 60-80% of calories
      The best way is to actually track all your food for at least 1-2 days. Use an app like FatSecret, KetoDietApp or CarbManager to help you.
      Then you can compare the amounts you are eating with the target range, to check if you are getting too much protein.
      If you want to calculate more precise nutrient targets for yourself individually, use a Keto macro calculator.

    1. Hi Jay, do you mean 75g of carbs a day? That’s way too high for ketosis, but too low for a standard high-carb diet. So I am not surprised if you feel crap.
      if you want to go low-carb, you need to drop your carbs to about 20g a day – and wait for ketosis, after which you will feel much better. Or you could just go back up to eating a standard diet with about 200-300g of carbs a day.

  19. I feel too nauseous and light headed to eat anything, had 2 pieces of toast in 24hrs think I just want to stop it now!

    1. Hi E, that does not sound good at all 🙁 Keto flu doesn’t usually cause nausea. Stopping the diet was a good idea. I would recommend discussing keto with your doctor before you try it next time, in case you have any individual contra-indications.

        1. Thanks ReeRee. Would you care to share links to these materials, or titles of the books, where you got this information from? I have not come across this symptom being described as common – but perhaps I am wrong.

          1. This is the second time I have done no/low carb…the first time was back in 2003, I did so well, stuck strictly by the book (atkins) and lost 44 lbs in no time. I got bored however and fell off the wagon. This is my second attempt, Im on day 4 and feel AMAZINGGGG. The ONLY problem I’ve encountered is nausea. Last night I ate a half a pack of antiacids. It was bad. My thought: Maybe too much oil and butter?? Not sure, but I have a long way to go, and am excited about trying new low carb recipes. 3lbs down, btw.

          2. Thanks for sharing your experience, Shelby. Too much fat could be the reason, especially if you are not used to it. Best of luck with your diet!

          3. I believe the reason some people notice nausea on a keto diet is because they are eating too much dairy. Most people can’t properly digest dairy the way that we’d like.. causing an upset stomach. I know when I first started keto I got most of my fats from cheese and I was feeling horrible from it. Now I only eat cheese a couple or few times a week, instead of everyday.

          4. Carbophobic (SITE AUTHOR)

            That makes perfect sense – thank you for sharing this tip, Nicolenna. Indeed, dairy can be a bit tricky for many of us.

  20. Pingback: 7 Ways to Fight Fatigue on a Low-Carb Diet - Advanced Nutrition Associates

  21. Hi,
    In your article “8 Ways to Blast through Low-Carb Flu and Dive into Ketosis” please change point in Item (1) to read “•Add butter,Olive and Coconut oils to your cooked vegetables and salads.
    Omega-6 Vegetable oils are toxic and inflammatory.

  22. Pingback: New Year Round-Up: Top Low-Carb Diet Tips – Low Carb Diet Support

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