40 Fun Facts About Ketogenic Diet

The ketogenic diet was developed by doctors in the 1920s to treat which neurological condition in children?

Epilepsy drugs such as phenytoin pushed the diet aside from 1938, and it stayed out of fashion until the 1990s.

Which solvent gives the fruity smell of so-called keto breath?

Acetone, the solvent in nail polish remover, is one of the three ketone bodies, and it is so volatile that the body gets rid of it through the lungs.

Which vegetable do keto cooks pulse into rice, mash like potatoes and bake into pizza crust?

Cauliflower is 92% water and only about 5% carbohydrate, which is why it can stand in for so many starchy staples.

Bulletproof coffee, inspired by a traditional tea its creator drank in Tibet, is blended with which dairy product?

Butter went into Dave Asprey's morning coffee after he tasted Tibetan tea made with yak fat, and he posted the recipe on his blog in 2009.

A typical keto limit of 50 grams of carbohydrate a day is less than the amount in one medium plain what?

Bagel fans face the starkest cut: one medium plain one holds more carbohydrate than a whole day's keto allowance, and stricter plans go as low as 20 grams.

Keto dieters at In-N-Out can order a burger Protein Style, which replaces the bun with large leaves of what?

Lettuce has wrapped In-N-Out's bunless Protein Style burgers since the 1970s, one of the unadvertised options on the chain's so-called secret menu.

Which Oscar winner played a mother seeking ketogenic treatment for her son in the 1997 TV film ...First Do No Harm?

Meryl Streep earned Emmy and Golden Globe nominations for the role, in a story that director Jim Abrahams drew from his own son Charlie's experience.

Which popular snack, botanically a legume and not a true nut, sits on Harvard's keto not-allowed list?

Peanuts are ruled out alongside beans and lentils on strict keto food lists, while tree nuts such as pecans and walnuts are welcome.

Which organ turns fat into the ketone bodies that fuel the body when carbohydrates run low?

The liver makes ketone bodies from fat but lacks the enzyme needed to burn them, so it ships them all out for other tissues to use.

Which hormone falls after a few days of carbohydrate restriction, signalling the body to switch to burning fat?

Insulin normally tells the body to store fuel; when levels drop, fat cells release their fatty acids into the blood to be burned instead.

On a ketogenic diet, ketone bodies stand in for which sugar that is normally the main energy source for cells?

Glucose reserves are small: after three to four days without carbohydrate they are fully depleted, and the body turns to fat for fuel.

Unlike fatty acids, ketone bodies can cross a protective barrier in the bloodstream to fuel which organ?

The brain cannot burn fatty acids directly, yet after about 24 days without food ketone bodies supply up to two-thirds of its fuel.

Ketoacidosis, a dangerous blood condition often confused with ketosis, most commonly affects people with which illness?

Type 1 diabetes leaves ketone production unchecked, so blood levels can pass 10 millimolar, against roughly 0.5 to 3 in the ketosis of a low-carb diet.

Which stored carbohydrate, held in muscle with three to four parts water, must run low before ketosis begins?

Glycogen is the body's quick-access carbohydrate reserve, and the stores are typically used up within the first 24 hours without food.

Doctors devised the ketogenic diet in 1921 to imitate the metabolic effects of which far older medical remedy?

Fasting had been prescribed since ancient Greece, but no patient can keep it up; Russell Wilder wanted its benefits in a form that could be maintained indefinitely.

Russell Wilder coined the term ketogenic diet in 1921 while working as a physician at which American medical centre?

Mayo Clinic paediatrician Mynie Peterman then fixed the classic recipe: a gram of protein per kilo of body weight, 10 to 15 grams of carbohydrate a day, and fat for everything else.

Which cardiologist turned low-carbohydrate eating into a 1970s craze with his bestselling book Diet Revolution?

Robert Atkins based the 1972 bestseller on a regime he had been prescribing to his own patients through the 1960s.

Keto dieters calculate net carbs by subtracting sugar alcohols and which other nutrient from total carbohydrates?

Fiber passes through the gut unabsorbed, though Harvard warns that net carbs is an unregulated term invented by food manufacturers as a marketing strategy.

MCT oil, prized on keto because it yields more ketones than other fats, comes from the oil of which plant?

Coconut oil is rich in medium-chain fats, which are absorbed more quickly than ordinary long-chain ones; a 1971 hospital keto diet drew 60% of its calories from MCT oil.

Which fruit is a keto favourite because about 75% of its energy comes from fat, mostly the monounsaturated kind?

Avocado flesh is about 15% fat, a markedly higher share than most other fruit, which made it a staple wherever meat and dairy were hard to come by.

Which nut is ground into the meal that has become a baking staple for people on low-carbohydrate diets?

Almond meal was a pastry ingredient long before keto: it goes into French macarons and frangipane, and it is one of the two main ingredients of marzipan.

Shirataki noodles, a very low-calorie pasta swap whose name means white waterfall, are made from which plant?

Konjac noodles are 97% water and only 3% plant matter, taken from the underground stem of a species also known as devil's tongue.

Which zero-calorie sugar substitute comes from the leaves of a plant native to Paraguay and Brazil?

Stevia's plant was called sweet herb by the Guaraní peoples of South America, who used the leaves for centuries to sweeten their teas.

Which nut, first farmed on a large scale in Hawaii, is prized on keto because it is about 76% fat?

Macadamia trees are native to Australia, the only widely grown food plant that is, yet Hawaii was the world's largest producer for more than a century.

Which crunchy snack, known in Mexico as chicharrones, is a low-carbohydrate alternative to potato chips?

Pork rinds are fried pig skin, so a serving has almost no starch and, by one magazine's count, nine times the protein of potato chips.

Full-fat milk is restricted on keto, though hard cheeses are often allowed, because milk is high in which natural sugar?

Lactose also puts cream and ice cream on the restricted list, while hard cheeses pass because they contain far less of it.

Which fruits does Harvard's keto guide allow in small portions because they are lower in net carbs than others?

Berries are the exception to a strict rule: most other fruits, and every fruit juice, sit on the guide's not-allowed list.

Keto programmes often recommend beef raised on which feed, said to offer slightly higher amounts of omega-3 fats?

Grass-fed beef is recommended over grain-fed by many keto programmes, and free-range poultry is suggested for the same omega-3 reason.

Which hospital, whose method of starting the ketogenic diet is widely copied, treated Charlie Abrahams in the 1990s?

Johns Hopkins had kept offering the diet through its lean decades, and Charlie's father found it only through a reference in a guide for parents.

Children starting the classic ketogenic diet in hospital are first given small meals of which festive-sounding drink?

Eggnog, made to the hospital's ketogenic recipe, is served at one-third of a normal meal's calories on day one and two-thirds on day two, before solid keto meals begin.

About one in 20 children on the medical ketogenic diet develops which painful but treatable complication?

Kidney stones are far rarer in other children; hospitals once raised the risk by restricting how much water children on the diet could drink, a rule since dropped.

Which English undertaker wrote an 1863 low-carb pamphlet so widely read that his surname became a word for dieting?

William Banting, a coffin maker who had been obese, gave up bread, milk, sugar, beer and potatoes and described the results in his Letter on Corpulence.

Which Arctic explorer spent a year on an all-meat, near-zero-carb diet, monitored at New York's Bellevue Hospital?

Vilhjalmur Stefansson did it alongside fellow explorer Karsten Anderson, in a study that was paid for by the American Meat Institute.

The most common ketosis test strips turn from pink to maroon when dipped in which body fluid?

Urine strips react to only one of the three ketone bodies, and the reading shifts with how much water a person has been drinking.

Ketosis is also a common veterinary problem in which farm animals in the first weeks after giving birth?

Cattle making milk for a newborn calf can burn more energy than they manage to eat, so vets screen dairy herds for ketosis with on-the-spot tests.

Which ketone body, the most abundant one circulating in the blood, is measured by finger-stick ketone meters?

Beta-hydroxybutyrate dominates in the blood, but dip strips detect a different ketone body, so the two kinds of test often disagree.

Which TV newsmagazine's 1994 report on young Charlie Abrahams brought the ketogenic diet back to national attention?

Dateline aired the story in October 1994; a multi-hospital study that began the same year set off an explosion of scientific interest in the diet.

Which hormone, nicknamed the hunger hormone, stayed flat in one study of obese adults while they were in ketosis?

Ghrelin is made mostly in the stomach, and in the eight-week study it surged, along with the urge to eat, only once the dieters came out of ketosis.

Which blood measure, watched for heart health, may rise by around 30% in children on the ketogenic diet?

Cholesterol readings can be brought back down by swapping some saturated fat for polyunsaturated fat or, if that fails, by easing the diet's fat ratio.

Ketone bodies are assembled mainly inside which structures within the body's cells?

Mitochondria are also where fatty acids are burned for energy, which is why red blood cells, having none, cannot use fat at all.