Low carbohydrate diets advocates that we restrict the carbohydrate intake to as little as 20 grams a day or less if better depending on the program. However the Food and Nutrition Board of the Institute of Medicine of the academies of Science recommended that the daily allowance of carbohydrates for young adults should not fall below the minimum of 100 grams.

As early as 2004, both the Atkins Nutritionals and Dr. Barry Sears, creator of "The Zone", stated that they do not recommended their products for these people and only market their dieting programs to older adults only. Dr. Arthur Agatston, the author of the South Beach Diet does recommend his plan for young adults, but they have to omit the first phase of his two weeks introductory program.

Drs. Michael and Mary Dan Eades, creator of Protein Power, says that their programs can be used on these young people so long as they start in phase two. SugarBusters, which is less restrictive in terms of carbohydrate allowances, has a separate plan for these young people.

The carbohydrates that you consume in food are the main source for cellular energy and central nervous systems functioning. Carbohydrates convert to glucose and the pranceas pumps out insulin that unlocks cells and allows the glucose energy inside. Low carb advocates says that consuming too much carbohydrate overload this finely balanced system and triggers the release of too much insulin which eventually will be stored as fats. Too much circulating insulin is also associated with insulin resistance and raises heart diseases risk.

Many low carbohydrate diets replace sugar and starches with protein rich food such as red meat and eggs. Critics of carbohydrate reduction say that the high levels of artery clogging fats and cholesterols from such foods are a one way ticket to heart diseases.

However some studies have found that after six to twelve months, many people on a reduced carbohydrate diet have actually improved their blood cholesterol level. But there are no studies longer than a year that measure the impact of these low carbohydrate and high protein diets on the cardiovascular system. Until now, we still do not have enough evidence and the jury is still out.