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 >
Fairly recently, the diet was introduced as a weight-loss diet by an Italian professor of surgery, Dr. Gianfranco Cappello of Sapienza University in Rome. In his 2012 study, about 19,000 dieters received a high-fat liquid diet via a feeding tube inserted down the nose. The study showed an average weight loss of more than 20 pounds in participants, most of whom kept it off for at least a year. The researchers reported a few minor side effects, like fatigue.
First reported in 2003, the idea of using a form of the Atkins diet to treat epilepsy came about after parents and patients discovered that the induction phase of the Atkins diet controlled seizures. The ketogenic diet team at Johns Hopkins Hospital modified the Atkins diet by removing the aim of achieving weight loss, extending the induction phase indefinitely, and specifically encouraging fat consumption. Compared with the ketogenic diet, the modified Atkins diet (MAD) places no limit on calories or protein, and the lower overall ketogenic ratio (approximately 1:1) does not need to be consistently maintained by all meals of the day. The MAD does not begin with a fast or with a stay in hospital and requires less dietitian support than the ketogenic diet. Carbohydrates are initially limited to 10 g per day in children or 20 g per day in adults, and are increased to 20–30 g per day after a month or so, depending on the effect on seizure control or tolerance of the restrictions. Like the ketogenic diet, the MAD requires vitamin and mineral supplements and children are carefully and periodically monitored at outpatient clinics.[47]
The ketogenic diet tries to bring carbohydrates down to less than 5 percent of a person’s daily caloric intake – which means eliminating most grains, fruit, starchy vegetables, legumes and sweets. Instead, it replaces those calories with fat. That fat is turned into ketone bodies, which are an alternative energy source: besides glucose derived from carbohydrates, ketones from fat are the only fuel the brain can use.

Many ketogenic dieters also swear by MCT oil. (MCT simply stands for medium chain triglycerides.) MCT's energy-sustaining powers can be explained as follows: When MCT oil is metabolized in the body, it behaves more like a carbohydrate than a fat. Unlike other fats, MCT oil does not go through the lymphatic system. Instead, it is transported directly to the liver where it is metabolized so it releases energy like a carbohydrate and creates lots of ketones (which can be used for fuel) in the process.

Still, it can be hard to get enough fat when you first start this diet. Butter, nuts, coconut and olive oils, and fatty cuts of meat are all on the menu. However, don't go overboard with polyunsaturated fats like soybean, corn, or sunflower oil. Keto dieters who increase their intake of those fats often end up with gastrointestinal distress that causes them to jump ship.


As for branched-chain amino acids, you'll find smart people who swear that they're keto-friendly, and others who don't. One of the BCAAs, valine, can be glucogenic, meaning that it can lead to glucose production and potentially contribute to leaving ketosis behind.[1] But does that mean it will happen? Not necessarily, particularly if you're just an occasional supplement user.

A study with an intent-to-treat prospective design was published in 1998 by a team from the Johns Hopkins Hospital[19] and followed-up by a report published in 2001.[20] As with most studies of the ketogenic diet, there was no control group (patients who did not receive the treatment). The study enrolled 150 children. After three months, 83% of them were still on the diet, 26% had experienced a good reduction in seizures, 31% had had an excellent reduction and 3% were seizure-free.[Note 7] At twelve months, 55% were still on the diet, 23% had a good response, 20% had an excellent response and 7% were seizure-free. Those who had discontinued the diet by this stage did so because it was ineffective, too restrictive or due to illness, and most of those who remained were benefiting from it. The percentage of those still on the diet at two, three and four years was 39%, 20% and 12% respectively. During this period the most common reason for discontinuing the diet was because the children had become seizure-free or significantly better. At four years, 16% of the original 150 children had a good reduction in seizure frequency, 14% had an excellent reduction and 13% were seizure-free, though these figures include many who were no longer on the diet. Those remaining on the diet after this duration were typically not seizure-free but had had an excellent response.[20][21]


It is also worth considering that eating a well balanced, keto diet is actually very expensive. For most people, following a low carbohydrate diet, rather than a no carbohydrate diet, is much more practical – as it will also allow for the inclusion of fruit and all vegetables. This represents much better dietary balance and usually leads to people sticking with it for longer.
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For athletes, research on the keto diet highlights potential improvements in athletic performance, especially when it comes to endurance activities. An article suggests ketogenic-type diets may allow endurance athletes to rely mostly on stored fat for energy during exercise rather than having to refuel with simple carbohydrates during endurance training and competition while additionally improving recovery times. (10)
I have a question on sugar since I see it’s not allowed. Is splenda or any other sugar subsitute ok? What if one of the ingredients that is required for a keto recipe contains sugar, does it matter? I haven’t really seen any discussion on how some things may already contain sugar (even if in low doses) may affect the keto diet. Should they be avoided altogether?
Blanket statement: It’s always best to check with your doctor before starting on this regimen. With that said, “the keto diet isn’t recommended for those with liver or kidney disease, or someone with a medical condition, such as a gastrointestinal issue, who can’t metabolize high amounts of dietary fat,” says Sarah Jadin, a Los-Angeles based registered dietitian and founder of Keto Consulting, LLC. If you’ve had your gallbladder removed, the keto diet may be a no-go. Women who are pregnant or breastfeeding and people with certain rare genetic disorders shouldn’t try this diet.
We know the keto diet restricts carbohydrates, but what can you eat? Actually carbohydrates are allowed, but in very small amounts — less than 30 grams per day (for perspective, a medium apple contains about 25 grams of carbs). The diet focuses on meats, eggs, cheese, fish, nuts, butters, oil, heavy cream, mayonnaise and low-carb vegetables such as kale and broccoli. 
How often you eat is also up to your personal preference. "For most people, I recommend three to four meals per day with a few healthy keto snacks in between," says Dr. Axe. "This ensures that you're getting a good mix of protein and fat all day long to keep you feeling energized and satisfied." That being said, he encourages people to listen to their bodies and tune in to when they're truly hungry. "If you find that you feel better eating five to six smaller meals spread throughout the day, do what works best for you."

Hi Melissa! Thanks for this an awesome resource, thank you so much! A quick question – do you have any suggestions for doing keto with a milk allergy? I’m gluten and dairy free due to food sensitivities, but I’d love to try keto – the only problem is that 99% of the keto recipes/guides/meal plans that I’ve found a full of DELICIOUS but evil cheese! Thanks for your help :)
Dinner: In a small sauce pan bring 2-3 cups of water to the boil. Cook a large egg in rolling boil for 5 minutes, then transfer to ice bath (a bowl with cold water and ice cubes in it). Wash and spin dry butter lettuce, top with sliced avocado and hemp seed. Serve soft boiled egg with cherry tomatoes, butter lettuce salad and mayonnaise as dressing.

The keto diet does provide short-term benefits, but the long-term benefits are still unknown. Researchers caution that a very low  carb diet can be difficult to maintain long term, leading to “yo-yo” dieting and increased weight gain. Researchers suggest that the keto diet can be used to kick start weight loss, but should be followed up with healthy eating plans that can be sustained long term.
Conklin's fasting therapy was adopted by neurologists in mainstream practice. In 1916, a Dr McMurray wrote to the New York Medical Journal claiming to have successfully treated epilepsy patients with a fast, followed by a starch- and sugar-free diet, since 1912. In 1921, prominent endocrinologist Henry Rawle Geyelin reported his experiences to the American Medical Association convention. He had seen Conklin's success first-hand and had attempted to reproduce the results in 36 of his own patients. He achieved similar results despite only having studied the patients for a short time. Further studies in the 1920s indicated that seizures generally returned after the fast. Charles P. Howland, the parent of one of Conklin's successful patients and a wealthy New York corporate lawyer, gave his brother John Elias Howland a gift of $5,000 to study "the ketosis of starvation". As professor of paediatrics at Johns Hopkins Hospital, John E. Howland used the money to fund research undertaken by neurologist Stanley Cobb and his assistant William G. Lennox.[10]

When you eat tons of carbs, your blood sugar is consistently elevated, and then so is insulin. Insulin is a hormone that keeps your blood sugar in check by shuttling the glucose into cells, but when there’s a consistently high amount of insulin, your cells become resistant. This insulin resistance makes it easier to store fat, and chronically high levels of insulin also cause excessive inflammation in the body, which contributes to heart disease, high blood pressure, and potentially type 2 diabetes.
I would get seriously scientific. I happen to be diabetic and test my blood sugar on a regular basis. I had to keep testing my blood sugar after I started Keto as it is a requirement for me. I was flabbergasted by the numbers that started turning up. It is an additional point of data and can sometimes be very eye-opening. My tester helped me discover certain keto friendly foods that I don’t tolerate. You can pick up a tester at the pharmacy. I can’t say that pricking your finger several times a day is fun but it will give you a good read on how your body is reacting to certain meals and ingredients.
The ketogenic diet—also known as "keto"—has become the latest big thing in weight-loss plans, touted recently by celebs like Jenna Jameson, Mama June, and Halle Berry. The diet involves cutting way back on carbohydrates, to 50 grams a day or less, to help the body achieve a state of ketosis, in which it has to burn fat (rather than sugar) for energy.
Conklin's fasting therapy was adopted by neurologists in mainstream practice. In 1916, a Dr McMurray wrote to the New York Medical Journal claiming to have successfully treated epilepsy patients with a fast, followed by a starch- and sugar-free diet, since 1912. In 1921, prominent endocrinologist Henry Rawle Geyelin reported his experiences to the American Medical Association convention. He had seen Conklin's success first-hand and had attempted to reproduce the results in 36 of his own patients. He achieved similar results despite only having studied the patients for a short time. Further studies in the 1920s indicated that seizures generally returned after the fast. Charles P. Howland, the parent of one of Conklin's successful patients and a wealthy New York corporate lawyer, gave his brother John Elias Howland a gift of $5,000 to study "the ketosis of starvation". As professor of paediatrics at Johns Hopkins Hospital, John E. Howland used the money to fund research undertaken by neurologist Stanley Cobb and his assistant William G. Lennox.[10]

If you talk to keto aficionados, you’ll find many save leftovers from dinner for the next day’s lunch. Cook once, eat twice—your keto diet menu for lunch is solved. If you don’t like leftovers or if you’re craving something different for lunch, the mid-day meal can be as simple as a scoop of chicken salad. Or, hit the salad bar at a local grocery store and top a bowl of greens with some good-fat goodies. You can also try one of these simple keto lunches:

Keep eating low carb to continue losing weight, feeling good and becoming healthier!Try making any of our hundreds of recipes available on the site. We make sure each and every recipe is delicious, nutritious and will keep you under your daily carb limit, even if you go for seconds. In addition, we provide step-by-step instructions to make the process as easy as possible. If you ever run into any issues or have any questions, be sure to leave a comment or contact us directly! We’re always happy to help.
when progress stalls there are three things to consider. 1: You can try to ride it out. Your body might be making some “behind the scenes” adjustments and once these are done you will start to loose again. 2: You will have to change either the intensity or the length of your exercise sessions. 3: In addition, you might have to tighten up on your calories. Have You been tracking your calories?…
The ketogenic diet tries to bring carbohydrates down to less than 5 percent of a person’s daily caloric intake – which means eliminating most grains, fruit, starchy vegetables, legumes and sweets. Instead, it replaces those calories with fat. That fat is turned into ketone bodies, which are an alternative energy source: besides glucose derived from carbohydrates, ketones from fat are the only fuel the brain can use.

To prevent side effects such as the keto flu, begin transitioning your meal plan gradually. Start by understanding how many carbohydrates you take in most days. Then begin slowly reducing your carbohydrate intake over a period of a few weeks while gradually increasing your intake of dietary fat to keep your calories the same. You should also make sure to seek guidance from a professional to make sure this plan works best for you and your health goals. “See a dietitian and adapt the diet to fit your long-term needs,” Spano recommends.


because the recipes don’t mention quantities it’s hard to know how much it’s okay to eat of the carb foods. How much carbs is in those foods like kale, cauliflower, lettuce a.s.o. What about mushrooms ? Love to use them as a ‘filler’ instead of bread. Also hard to know how much is too much protein? Cheese, meat, bacon, yoghurt, tuna…. they all are full of protein.
Thanks for all the good info! I continue to come back and re-read some posts to stay motivated and informed. I have been low carb for about 1.5 months and have lost about 18 pounds. But I continue to have awful night sweats and periods of “flashes” during the day. Would that be considered some of the hormonal changes you referred to? They are very aggravating and interrupt my sleep. BUT they are worth it for the positive effects!
You may also be a great candidate for the Keto diet if you experience migraines, joint pain, muscle weakness or mental fatigue. In addition, "Keto diet can be beneficial for mental health conditions like depression, autism and Alzheimer's". Other than that, "you can also follow this diet plan if you're trying to get pregnant since it improves fertility", she notes.
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.
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