What Does "Low-Carb" mean?
moderate protein (e.g., meat, poultry, fish, shellfish, eggs, cheese, nuts, and seeds) and other foods low in carbohydrates (e.g., most salad vegetables such as spinach, kale, chard and collards), although other vegetables and fruits (especially berries) are often allowed. The amount of carbohydrate allowed varies with different low-carbohydrate diets.
Such diets are sometimes 'ketogenic' (i.e., they restrict carbohydrate intake sufficiently to cause ketosis).
The term "low-carbohydrate diet" is generally applied to diets that restrict carbohydrates to less than 20% of caloric intake, but can also refer to diets that simply restrict or limit carbohydrates to less than recommended proportions (generally less than 45% of total energy coming from carbohydrates).
Low-carbohydrate diets are used to treat or prevent some chronic diseases and conditions, including cardiovascular disease, metabolic syndrome, auto-brewery syndrome, high blood pressure, and diabetes.
In the 1990s, Atkins published an update from his 1972 book, Dr. Atkins New Diet Revolution, and other doctors began to publish books based on the same principles. This has been said to be the beginning of what the mass media call the "low carb craze" in the United States. During the late 1990s and early 2000s, low-carbohydrate diets became some of the most popular diets in the US. By some accounts, up to 18% of the population was using one type of low-carbohydrate diet or another at the peak of their popularity, and this use spread to many countries. Food manufacturers and restaurant chains like Krispy Kreme noted the trend, as it affected their businesses. Parts of the mainstream medical community has denounced low-carbohydrate diets as being dangerous to health, such as the AHA in 2001, the American Kidney Fund in 2002, Low-carbohydrate advocates did some adjustments of their own, increasingly advocating controlling fat and eliminating trans fat.
Proponents who appeared with new diet guides at that time like the Zone diet intentionally distanced themselves from Atkins and the term 'low carb' because of the controversies, though their recommendations were based on largely the same principles . It can be controversial which diets are low-carbohydrate and which are not. The 1990s and 2000s saw the publication of an increased number of clinical studies regarding the effectiveness and safety (pros and cons) of low-carbohydrate diets .
In the United States, the diet has continued to garner attention in the medical and nutritional science communities, and also inspired a number of hybrid diets that include traditional calorie-counting and exercise regimens. Other low-carb diets, such as the Paleo Diet, focus on the removal of certain foods from the diet, such as sugar and grain. On September 2, 2014 a small randomized trial by the NIH of 148 men and women comparing a low-carbohydrate diet with a low fat diet without calorie restrictions over one year showed that participants in the low-carbohydrate diet had greater weight loss than those on the low-fat diet. The low-fat group lost weight, but appeared to lose more muscle than fat.