These diets typically involve eating lots of meat, poultry, fish, eggs, cheese and fats; severely restricting carbohydrate-rich foods such as bread, potatoes, cereals and sugars; and limiting most fruits and some vegetables. There is no special magic to these diets; they’re just low calorie diets with a strict and novel set of dietary rules. This means that you end up eating less than usual, and lose weight. Vitamin and mineral supplements are needed, as the diets are not nutritionally adequate. They’re not safe for people with medical conditions such as heart, liver or kidney disease and gout.

A main concern is their restriction of whole grains and many fruits and vegetables (which help protect against cancer and heart disease), and unless lean meats and low fat cheeses are chosen, saturated fat intake is high. There is also currently no evidence that low carb. diets are either healthy to follow, nor help people control their weight in the long-term. But we do know that healthy, balanced diets can achieve both of these things.