The aim is far broader than suggested by the article here: It’s not just about what you put in your mouth – it’s also about timing and exercise. There are three ways to be in ketosis – which simply means that “fat burning” and not being dependent on sugars. Fasting puts a man into ketosis in 3 days and a woman by 2 days. Endurance exercise gets you there in a couple of hours. Eating a high fat diet will do it too. The goal however is hidden by the detail – it is to acquire a “Flexible Metabolism”. The aim is to switch on the full fat burning capacity and keep it running – which takes from between 4 to 12 weeks physical adaptation (for the muscles to fully be able to use ketones). The heart runs approximately 27% more efficiently on ketones than on glucose! The brain works better too – Alzheimer’s being referred to by researchers as “diabetes 3”. Once you have a Flexible Metabolism you can consume carbs during or after exercise without dropping out of ketosis – though this depends on your own bio-individuality. I can eat quite a lot of carbs – without losing ketosis – my partner cannot.

On the ketogenic diet, carbohydrates are restricted and so cannot provide for all the metabolic needs of the body. Instead, fatty acids are used as the major source of fuel. These are used through fatty-acid oxidation in the cell's mitochondria (the energy-producing parts of the cell). Humans can convert some amino acids into glucose by a process called gluconeogenesis, but cannot do this by using fatty acids.[56] Since amino acids are needed to make proteins, which are essential for growth and repair of body tissues, these cannot be used only to produce glucose. This could pose a problem for the brain, since it is normally fuelled solely by glucose, and most fatty acids do not cross the blood–brain barrier. However, the liver can use long-chain fatty acids to synthesise the three ketone bodies β-hydroxybutyrate, acetoacetate and acetone. These ketone bodies enter the brain and partially substitute for blood glucose as a source of energy.[55]

Elena Paravantes, RDN is a Registered Dietitian Nutritionist, Writer and consultant specializing in the Greek Mediterranean Diet and Cuisine. She has been active as a clinician, consultant and lecturer for 20 years, both in the U.S. and Greece. An expert on the Greek Mediterranean Diet, her interviews and articles have been published in many publications including CNN, U.S. News and World Report, Prevention, NPR, and Shape. Elena has collaborated with a number of organizations including Loyola University, Yale University, University of Missouri, Louisiana State University, and the American College of Greece.

The plan promotes long-lasting, sustainable changes, and undoubtedly a bounty of research backs this up. In fact, one December 2013 study in the American Journal of Medicine shows that people following Weight Watchers were close to nine times more likely to lose 10 percent of their body weight, compared to people following a self-help diet plan. (20)


Full disclosure: I have followed a low-carb diet for nearly a decade and find no problem adhering to it. I’ve lost weight and all my cardiovascular biomarkers have improved. Moreover, I’ve studied the science and history behind low-carbohydrate diets, so beyond my personal experience, I bring an evidence-based perspective. (Previously, for 25+ years, I adhered faithfully to a “mostly plants” regimen of fruits, veggies, and whole grains, including my own homemade 7-grain bread, while exercising religiously. Yet during that time my blood lipids were unhealthy, and I never could shake an extra 10-20 pounds.)
The diet that brought ‘lectins’ into the mainstream - a plant-based protein found in the likes of legumes (lentils and beans), nightshade veg (tomatoes, potatoes and aubergine), eggs and grains. The man who popularised the lectin-free diet – Dr Steven Gundry – describes them as ‘toxic’. In his book that brought a lectin-free lifestyle to the masses – The Plant Paradox – he cites them as the source of modern ailments from obesity to gastrointestinal disorders.
4. Better eyesight. The diet could help stave off or prevent macular degeneration, the leading cause of vision loss after age 54. The condition, which affects more than 10 million Americans, destroys the part of your retina responsible for the clear central vision you need to read, drive, and recognize faces. A recent study linked eating fish and vegetables to a reduced risk of getting it early, and the omega-3 fatty acids in fish can lower the risk of the disease altogether. What's more, the lutein in green leafy vegetables cuts your chance of cataracts and boosts retinal health, says Dr. Willett.
If the diet is a quick fix rather than one that promotes lasting lifestyle changes, this could pose a problem. In particular, extreme diets that promise big weight loss up front aren’t always sustainable — and you may end up overeating or even binge eating if you feel deprived. “Consider if the diet’s habits are ones you can continue throughout your lifetime, not just 21 or 30 days,” says Angie Asche, RD, a sports dietitian in Lincoln, Nebraska.

Hello, I am hoping someone can reach out to me and explain something. My son who is T1D just started the keto diet 4 days ago. At first we were doing great numbers were good, then out of nowhere we are having highs! He is correcting and it’s not bringing him down into normal range. I am going into a panic, I don’t know what to do, or who to ask for help. His doctor would be no help, and thinks the Standard American Diet is fine. I don’t see eye to eye with him. I hope someone can tell me why this might be happening. Thanks in advance for your time!


Over 8–10 mmol/l: It’s normally impossible to get to this level just by eating a keto diet. It means that something is wrong. The most common cause by far is type 1 diabetes, with severe lack of insulin. Symptoms include feeling very sick with nausea, vomiting, abdominal pain and confusion. The possible end result, ketoacidosis, may be fatal and requires immediate medical care. Learn more
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