Here are a few of the most common side effects that I come across when people first start keto. Frequently the issues relate to dehydration or lack of micronutrients (vitamins) in the body. Make sure that you’re drinking enough water (close to a gallon a day) and eating foods with good sources of micronutrients. To read more on micronutrients, click here >

“Combining a super restrictive diet with long periods of non-eating is not good,” says Keatley. “The body will cannibalize its own muscle for energy if intake from food is too low but the body does not differentiate between something like a calf muscle or a heart muscle. Keep in mind all your important organs are made of smooth muscle and going on a diet like this may harm something like your bladder or lungs just as much as provide fat loss.”
Can’t you take ketone supplements? No. While it is possible to elevate ketones by taking them, “without the low-carb stimulus, there is no net increase in ketone production, no decrease in insulin, and no net increase in fat oxidation,” says Volek. Don’t trust trainers or “body hackers” who say you can induce ketosis quickly without changing your diet.
Electrolytes: To reiterate, maintaining electrolyte balances is critical on a ketogenic diet, in order to prevent side effects and the “keto-flu.” While this can be done exclusively through whole foods, some individuals may require additional sources. Sodium, magnesium, potassium, and in some cases, calcium, can all be replenished via supplementation.
You may also have to moderate protein intake somewhat, as high protein intake (greater than 2.0g/kg/d) may make it more difficult to maintain ketosis. However, eating too little protein may also present health issues such as poor muscle development, increased hunger, and lack of essential amino acids. That is why we recommend a moderate level of protein intake, defined as 1.2-1.7g/kg/d. See our protein guide.
One of the most common misconceptions about the keto diet is that you can eat as much protein as you’d like. But this is not a diet where you watch carbs only — you also have to keep your protein intake moderate, says Ginger Hultin, a Seattle-based registered dietitian, a spokesperson for the Academy of Nutrition, and the owner of ChampagneNutrition. Protein can be converted into glucose, and therefore overeating protein can take your body out of ketosis. Think of your ratios as a small portion of meat topped with a generous amount of fat, rather than the other way around.
Short-term results for the LGIT indicate that at one month approximately half of the patients experience a greater than 50% reduction in seizure frequency, with overall figures approaching that of the ketogenic diet. The data (coming from one centre's experience with 76 children up to the year 2009) also indicate fewer side effects than the ketogenic diet and that it is better tolerated, with more palatable meals.[18][50]
Unfortunately, there’s no long-term data on ketogenic diets versus other diets. In a 2015 Italian study, those on a ketosis diet lost 26 pounds in three months. About half of the participants stayed on the diet for a year but lost little additional weight in the next nine months. People in a 2014 Spanish study who followed a very-low-calorie ketogenic diet lost an average of 44 pounds in a year—but a third of them dropped out, possibly because it was too hard to maintain.
In addition to the traditional ketogenic and Atkins diets described above, there are modifications that can be implemented to both of these diets in order to produce greater benefits on an individual basis. One such amendment, called the Modified Atkins Diet (MAD), is structured similarly to the Atkins diet where protein and fat are consumed freely but carbohydrate intake is further restricted, providing an intermediary diet between Atkins and ketogenic diet. This approach is commonly being used with great success among children with epilepsy due to its ability to increase the likelihood of adherence to the diet while still minimizing glucose intake from dietary carbohydrates.[2]
Check the nutrition labels on all your products to see if they’re high in carbs. There are hidden carbs in the unlikeliest of places (like ketchup and canned soups). Try to avoid buying products with dozens of incomprehensible ingredients. Less is usually healthier.Always check the serving sizes against the carb counts. Manufacturers can sometimes recommend inconceivably small serving sizes to seemingly reduce calorie and carb numbers.

Because people with type 2 diabetes are at an increased risk for cardiovascular disease, there’s a specific concern that the saturated fat in the diet may drive up LDL, or “bad,” cholesterol levels, and further increase the odds of heart problems. If you have type 2 diabetes, talk to your doctor before attempting a ketogenic diet. They may recommend a different weight-loss diet for you, like a reduced-calorie diet, to manage diabetes. Those with epilepsy should also consult their doctor before using this as part of their treatment plan. 

There are several strategies for transitioning into a ketogenic state. Depending on a variety of factors and lifestyle habits, some individuals choose to ease into the process by adopting a low carbohydrate diet prior to implementing a full keto diet for beginners. One place to start would be to eliminate sugary, processed foods and replace those with whole, lower-carbohydrate foods. In doing so, you will begin to understand the keto diet for beginners, and once ready, you can dive into and customize the diet. To aid in the transition of a ketogenic lifestyle, our “Keto Calculator“ is an excellent resource!
Cramps: Due to the initial release of water when starting a keto diet for beginners, people often forget to replenish and hydrate. Due to this, some may experience “dry mouth.” An effective remedy is to ensure that there is sufficient consumption of water coupled with electrolyte balance. If dehydration persists, an increase in electrolytes may be needed (especially magnesium).
Although you'll be cutting way back on carbohydrates and sugar, some fruits are still okay to eat on the keto diet (though you'll still want to be mindful about quantity in order to remain in ketosis). The fruits that make the cut contain far fewer carbs than their off-limits cousins such as apples, pears, bananas, pineapples, papayas, grapes, and fruit juices in general.
Although studies have shown that the keto diet can reduce seizures for children with epilepsy, there is no evidence indicating that keto helps with other brain disorders or improves mental cognition, according to Harvard Health Publishing. Some studies show that keto may lower blood sugar for people with type 2 diabetes, but there is not enough long-term research to determine whether it’s safe and effective for diabetics.
"Plenty of people jump right in, thinking all they have to do is cut carbs and increase fat. All of a sudden, they hit a wall and get 'keto flu.' They feel tired, lethargic, and experience headaches," Wittrock says. "The primary reason they get these symptoms is lack of the three primary electrolytes: sodium, potassium, and magnesium. If you're deficient in any of these, you'll suffer mentally and physically. This is the single biggest reason people fail on the keto diet."
In order to maximize the benefits of a keto diet for beginners, self-experimentation to achieve an optimal level of ketosis is important. In addition to quantifying blood ketone levels, there are several biological changes that your body will experience to help identify a ketogenic state. These changes will be more robust for some, In contrast to the negative side effects often experienced while on other low-carbohydrate diets, a ketogenic state and “keto-adaptation” can elicit euphoric effects including:
By cutting carb intake significantly, we can drastically reduce insulin resistance, the precursor to type 2 diabetes. In addition, low carb diets, along with exercise, can be very effective at helping alleviate the symptoms and progression of type 2 diabetes. Beyond that, ketosis itself is appetite-suppressing, meaning your hunger will naturally check itself, increasing your caloric deficit and making you lose fat even faster. Read more about ketosis: What Is Ketosis, and How Long Does It Take to Get into Ketosis?
Although studies have shown that the keto diet can reduce seizures for children with epilepsy, there is no evidence indicating that keto helps with other brain disorders or improves mental cognition, according to Harvard Health Publishing. Some studies show that keto may lower blood sugar for people with type 2 diabetes, but there is not enough long-term research to determine whether it’s safe and effective for diabetics.
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