In a recent study in the Journal of Sports Medicine and Physical Fitness, Weiss and his colleagues found that participants performed worse on high-intensity cycling and running tasks after four days on a ketogenic diet, compared to those who’d spent four days on a high-carb diet. Weiss says that the body is in a more acidic state when it’s in ketosis, which may limit its ability to perform at peak levels.
Generally, the ketogenic diet reduces or excludes carbohydrate-containing foods, including breads, breakfast cereals, pasta, rice, quinoa, couscous, starchy vegetables (potato, sweet potato, corn), fruit, and legumes. Instead you are encouraged to consume more high fat foods, such as fatty meats, full-cream dairy, butter, nuts, avocado, olive oil and coconut oil.
Because some cancer cells are inefficient in processing ketone bodies for energy, the ketogenic diet has also been suggested as a treatment for cancer.[58][59] A 2018 review looked at the evidence from preclinical and clinical studies of ketogenic diets in cancer therapy. The clinical studies in humans are typically very small, with some providing weak evidence for anti-tumour effect, particularly for glioblastoma, but in other cancers and studies, no anti-tumour effect was seen. Taken together, results from preclinical studies, albeit sometimes contradictory, tend to support an anti-tumor effect rather than a pro-tumor effect of the KD for most solid cancers.[60]
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The ketogenic diet is not a benign, holistic or natural treatment for epilepsy; as with any serious medical therapy, there may be complications.[27] These are generally less severe and less frequent than with anticonvulsant medication or surgery.[27] Common but easily treatable short-term side effects include constipation, low-grade acidosis and hypoglycaemia if there is an initial fast. Raised levels of lipids in the blood affect up to 60% of children[37] and cholesterol levels may increase by around 30%.[27] This can be treated by changes to the fat content of the diet, such as from saturated fats towards polyunsaturated fats, and, if persistent, by lowering the ketogenic ratio.[37] Supplements are necessary to counter the dietary deficiency of many micronutrients.[3]
It's only when you combine lots of fat and lots of carbohydrates in your diet that you get into trouble. The sugar from the carbohydrates drives up your insulin levels, and those high insulin levels cause the body to mishandle the way fats are metabolized. More fat is stored or circulates in the blood. This causes the metabolic syndrome and weight gain associated with insulin resistance and starts the health problems that should be associated with a high carb diet, not a ketogenic diet plan.
Early studies reported high success rates: in one study in 1925, 60% of patients became seizure-free, and another 35% of patients had a 50% reduction in seizure frequency. These studies generally examined a cohort of patients recently treated by the physician (what is known as a retrospective study) and selected patients who had successfully maintained the dietary restrictions. However, these studies are difficult to compare to modern trials. One reason is that these older trials suffered from selection bias, as they excluded patients who were unable to start or maintain the diet and thereby selected from patients who would generate better results. In an attempt to control for this bias, modern study design prefers a prospective cohort (the patients in the study are chosen before therapy begins) in which the results are presented for all patients regardless of whether they started or completed the treatment (known as intent-to-treat analysis).[18]

On a ketogenic diet, your entire body switches its fuel supply to run mostly on fat, burning fat 24-7. Insulin levels become very low, and fat burning increases dramatically. It becomes easy to access your fat stores to burn them off. This is great if you’re trying to lose weight, but there are also other less obvious benefits, such as less hunger and a steady supply of energy. This may help keep you alert and focused.


There’s a lot of nut butters out there, but we found that this little guy not only tastes the best, it’s also one of the most filling on the market (i.e., you won’t be left dreaming of grape jelly and white bread). The density of healthy fats takes care of the stomach grumbling, while the four simple ingredients—macadamia nuts, coconut, cashews, and Himalayan sea salt—take care of your taste buds and fuel your body with oleic acid, minerals, and B vitamins.
Sometimes we all have leftover chicken on hand that needs to be used up. Maybe you roasted a couple of chickens on the weekend to prep for the week ahead, maybe you had company over and grilled up too many chicken breasts, or maybe rotisserie chicken was on sale at your local grocery store and it was too good a bargain to pass up. Whatever the reason, we all can use a few ideas on how to use up leftover chicken.
Your glycogen stores can still be refilled while on a ketogenic diet. A keto diet is an excellent way to build muscle, but protein intake is crucial here. It’s suggested that if you are looking to gain mass, you should be taking in about 1.0 – 1.2g protein per lean pound of body mass. Putting muscle on may be slower on a ketogenic diet, but that’s because your total body fat is not increasing as much.5Note that in the beginning of a ketogenic diet, both endurance athletes and obese individuals see a physical performance for the first week of transition.
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