Low-carb, no sugar, no fat: the fad diets popular in the 20th century

The feminine ideal of the New Woman in the 1920s with her slim, androgynous outline and increased spending power may have pushed the popularity of diets. Home weighing scales became common, as well as diet plans and books.

Avoiding carbs was central to many popular diets. Other diets, such as the salad days or fast-day diets, focused on limiting calories.

Slimming diets decreased in popularity during wartime and rationing but thrived in the years that followed - all to have a slim, beautiful body.

As before, low-carbohydrate approaches dominated, such as the crash diet, the third-day diet, and the daffodil diet. In the 1960s, the focus was on limiting portion sizes and consuming small amounts of calories.

Popular weight-loss regimes were talked up as self-help tools for the emancipated woman. Success and inner balance required control of the body through dieting and exercise.

The link between fitness and health caused fitness studios to become popular. Low-fat foods were emphasised. The famous F plan diet emphasised eating high fibre and low calories. At the end of the 20th century, diets such as the Atkins diet returned to Banting's emphasis on lowering carb intake.

Research shows fad diets may lead to weight gain and disordered eating, but fad diets continue to be popular despite this knowledge.

Modern diets such as keto or paleo share many similarities with the low-carb, calorie-restrictive diets. While the appeal to fad diets is understandable, a balanced diet and exercising is still the best way to maintain a healthy weight.