So, obviously lots of people are trying ketogenic diets for weight loss. That’s great! I really love seeing thousands of new people every year dip their toes into the keto pool and, hopefully, fall in love like I did. There are lots of great things about keto, and while some may try to sell it as a miracle diet that’s amazing and fun and delicious and totally picture perfect so everyone should do it ASAP — that’s not the case. You might be saying to yourself: “Duh, that’s so obvious, do you really need to explain this?” Trust me. I really do.
Like most things that seem sparkly and shiny and awesome with no drawbacks… there are a few drawbacks. I’ve talked at some length about a few drawbacks or reasons someone should not go on a keto diet in other posts around the site. This one, however, is dedicated to something very specific and actually quite common that I always see raising dozens of questions every time someone new starts keto. That, my curious friends, would be the so-called “keto flu.” Instead of letting wild internet myths and Facebook rumors fill our head with nonsense, we’re going to turn to our good friends at Harvard Health for some hardcore knowledge!
What is keto flu?
The keto flu is a set of symptoms that can emerge anywhere from two to seven days after beginning a ketogenic diet. Headache, foggy brain, exhaustion, irritability, nausea, difficulty sleeping, and constipation are just a few signs of this “medically undiagnosed” (aka not recognized as an official problem by modern medicine) disorder. On PubMed, a really handy repository of indexed medical research papers, a search for this phrase gives no results. An internet search, on the other hand, will turn up thousands of blogs and articles concerning the keto flu.
Because we are just left with our own observations and experiences, it is difficult to articulate exactly what happens following the diet change. These signs and symptoms may not be specific to the keto diet, though, some people report these same symptoms after cutting back on processed food intake or start an anti-inflammatory diet, so bear that in mind as well.
What causes keto flu?
To be totally frank and honest with you…. we’re not sure why some folks are feeling so awful after making this dietary change. Is there a link between it and a detox factor? Is it due to a carbohydrate deficiency? Is there any kind of immune response? Is it possible that this is due to a change in the gut microbiome? Whatever the case may be, it appears that the symptoms associated with the keto flu may occur in some people after “cleaning up” their diet.
There is also some speculation that the specific change your body undergoes when switching from burning carbs for energy to fat for energy is the main causal factor at work here. Those who are not as “metabolically flexible” are most affected by this switch and their body experiences great stress when making this dramatic change. Which, to be fair, does make a good bit sense — at least from an intuitive perspective.
Another theory is that the actual loss of carbohydrates in and of itself indirectly cause these symptoms due to dehydration. See, when your body stores carbohydrates to burn for energy later, it uses a lot of water for this storage. This is why you see people losing 5+ pounds of water weight in their first couple weeks of keto — you burn through all your carbohydrates to enter ketosis and as a result you lose all the water your body was holding onto for storing those carbs. Bam, huge loss of water means you become very dehydrated, hence the symptoms.
Okay, I have the keto flu. What do I do?
This is likely to happen to most people who make the switch to keto. Our bodies are so used to their dietary routines and this huge shift will probably cause at least some of these symptoms, if not the whole damn thing. Not to worry, though, there are some simple and effective remedies that I am more than willing to share with you right now! Try some of these, then see if you feel better:
- There’s no need to go out and buy any pricey supplements over the internet. Many websites are attempting to generate large sums of money by offering goods that claim to make you feel better but have no facts to back up their claims.
- This isn’t the flu, despite the name. You won’t get a fever, and the symptoms are unlikely to render you unconscious. If you’re feeling really bad, see your doctor because something else could be going on.
- Make sure you’re getting enough water. Dehydration is a side effect of some diets, especially this one.
- Eat more frequently and include a variety of colorful veggies in your diet. Switching from a typical American diet high in simple carbohydrates, trans fats, and saturated fat to a plant-based diet is a significant shift in how your cells use energy.
- Do not give up if you are committed to a plan. You may feel exhausted for a few days, but at the end of a week, your energy level will most likely return to normal and you may feel even better.
- Get some exercise, believe it or not. You’re probably not going to hit a PB during this time, but laying in bed like you might do with a regular flu isn’t going to help you in this scenario. Light exercise a couple times per week can help your body and mind feel much better.
- Your body is no longer getting energy from carbs so you may want to replace those calories by increasing your keto-friendly fat intake.
- If all else fails, consider easing into the new diet more slowly, instead of “cold turkey.”
The biggest thing here, guys, is to stick with it. There may be some undesired side effects at the onset of the diet — that is perfectly normal. You are stronger than keto flu. You are stronger than your weakest desires. You are stronger than your lowest impulses. There is no reason, at the end of the day, to let a few days of feeling under the weather determine what you put on your plate and how you treat your body.
If everything good was easy to do, we’d all be buff, angelic millionaires. Persevere through the hard stuff and I promise you the joy and satisfaction you feel at the end of this road will make any pain and struggle pale in comparison. Keep going, you got this!