This high-fat, adequate-protein, low-carb fad diet sends the body into a state of ketosis, in which the body uses stored fat for energy. Research published in Clinical Cardiology suggests the ketogenic, or “keto,” diet can be an effective weight loss method, but to be successful, you must follow the plan consistently with no cheat days — otherwise, you’re just eating a high-fat diet that may be high in unhealthy fats for no reason. (1) (A pro tip? If you're planning on doing the diet, consider perusing this complete keto food list and reading up on the healthiest fats for keto diet followers.)
In case you haven’t jumped on the keto train and are wondering what exactly all the hype is about, here you go: The diet is very high fat and (almost) no carb. The ratio of fat to carbs and protein is 4:1. The goal of the ketogenic diet is to burn fat for energy rather than carbohydrates, resulting in weight loss. And, advocates claim there are many benefits beyond the number on the scale going down.
Our bodies are incredibly adaptive to what you put into it – when you overload it with fats and take away carbohydrates, it will begin to burn ketones as the primary energy source. Optimal ketone levels offer many health, weight loss, physical and mental performance benefits.1There are scientifically-backed studies that show the advantage of a low-carb, ketogenic diet over a low-fat diet. One meta-analysis of low-carbohydrate diets showed a large advantage in weight loss. The New England Journal of Medicine study resulted in almost double the weight loss in a long-term study on ketone inducing diets.
The original therapeutic diet for paediatric epilepsy provides just enough protein for body growth and repair, and sufficient calories[Note 1] to maintain the correct weight for age and height. The classic therapeutic ketogenic diet was developed for treatment of paediatric epilepsy in the 1920s and was widely used into the next decade, but its popularity waned with the introduction of effective anticonvulsant medications. This classic ketogenic diet contains a 4:1 ratio by weight of fat to combined protein and carbohydrate. This is achieved by excluding high-carbohydrate foods such as starchy fruits and vegetables, bread, pasta, grains and sugar, while increasing the consumption of foods high in fat such as nuts, cream, and butter. Most dietary fat is made of molecules called long-chain triglycerides (LCTs). However, medium-chain triglycerides (MCTs)—made from fatty acids with shorter carbon chains than LCTs—are more ketogenic. A variant of the classic diet known as the MCT ketogenic diet uses a form of coconut oil, which is rich in MCTs, to provide around half the calories. As less overall fat is needed in this variant of the diet, a greater proportion of carbohydrate and protein can be consumed, allowing a greater variety of food choices.
Why was the DASH diet been ranked as the best diet, the healthiest diet, and the best diet for diabetes, 8 years in a row? The expert panel of physicians assembled by US New & World Reports chose DASH because it is proven to improve health, has a balance of healthy food groups, and it actually works. And now the Mediterranean diet has jumped out in front. So delicious and heart healthy. DASH has been proven to lower blood pressure and cholesterol, and is associated with lower risk of several types of cancer, heart disease, stroke, heart failure, kidney stones, reduced risk of developing diabetes, can slow the progression of kidney disease, and now is associated with reduced risk of depression.
The good news here is no! All the evidence points to the fact that a low carbohydrate diet actually does lower blood glucose and A1c levels and does contribute to weight loss. The problem is we do not yet have enough large studies, over enough sustained years to support evidence that people with diabetes can remain on a highly restrictive Ketogenic Diet for the rest of their life and also not have other consequences to their health.
The first meta-analysis worth noting collected the data from 10 randomized trials comprising 1376 participants in total.  After analyzing the research, a key relationship emerged between dietary carbs and blood sugar levels. In short, the researchers described their finding thus: “the greater the carbohydrate restriction, the greater glucose lowering…” 
Benefits It packs lycopene, a powerful antioxidant that is associated with a reduced risk of some cancers, like prostate and breast. Other components in tomatoes may help reduce the risk of blood clots, thereby protecting against cardiovascular disease, according to a review published in December 2013 in the journal Annual Review of Food Science and Technology. (9,10)
There isn't "a" Mediterranean diet. Greeks eat differently from Italians, who eat differently from the French and Spanish. But they share many of the same principles. Working with the Harvard School of Public Health, Oldways, a nonprofit food think tank in Boston, developed a consumer-friendly Mediterranean diet pyramid that offers guidelines on how to fill your plate – and maybe wineglass – the Mediterranean way.
Wondering what fits into a keto diet — and what doesn’t? “It’s so important to know what foods you’ll be eating before you start, and how to incorporate more fats into your diet,” says Kristen Mancinelli, RD, author of The Ketogenic Diet: A Scientifically Proven Approach to Fast, Healthy Weight Loss, who is based in New York City. We asked her for some guidelines.