The late Robert C. Atkins is the founder of the Atkins’ New Diet Revolution. He is also the founder and former director of Atkins Complimentary Medicine in New York, New York. The diet is a low carbohydrate, high fat diet without any restrictions on fat intake.

The diet begins with an induction phase (ranging from 2–36 weeks) limiting carbohydrate intake to only 20 grams per day. The consumption of fruit, bread, pasta, grains, starchy vegetables, and dairy other than cheese, cream, or butter are prohibited in this phase of the diet. There are two phases following the induction phase where daily carbohydrate intake is increased in weekly increments of 5 grams and 10 grams (1, 5). Then comes the maintenance phase, where dieters generally consume between 40–90 carbohydrates (4).

Proponents of high fat, low carbohydrate (CHO) diets dismiss the notion that caloric intake is important to either weight gain or weight loss (evidence contradicts this claim). They claim that “most overweight individuals do not overeat,” even as they suggest that high CHO meals leave individuals less satisfied than meals that contain adequate fat, resulting in increased hunger and increased food intake. With respect to weight loss, Atkins claims that on a low CHO diet, there are “metabolic advantages that will allow overweight individuals to eat as many calories as they were eating before starting the diet yet still lose pounds and inches” (3).

Furthermore, proponents contend overproduction of insulin, driven by high CHO intake, is the cause of the metabolic imbalance that underlies obesity. The overexaggeration of insulin’s role in obesity isn't uncommon and is often suggested by many of today’s most popular nutrition gurus. In reality, this issue has been blown out of proportion (3, 4). Reported subjects consuming 1000 calorie diets containing 15 percent CHO had significantly lower insulin levels compared with those consuming 45 percent CHO, yet there wasn't any difference in weight loss between the two groups. Similar results have been found in other studies.

My thoughts

Studies cited by Atkins to support his contentions were of limited duration and conducted on a small number of people. They lacked adequate controls and used ill-defined diets. Some of these, as well as other studies, actually refute the contention that low CHO diets, in the absence of calorie restriction, provide a metabolic advantage. Early studies on a limited number of obese men and women indicate individuals consuming low CHO diets reduce overall caloric intake and lose weight.

Consuming high amounts of protein in combination with low calcium and minimal fruit and vegetable intake could be detrimental to bone health (6). In many cases, low carbohydrate diets provide lower than recommended intakes of vitamin E, vitamin A, thiamin, vitamin B6, folate, calcium, magnesium, iron, potassium, and dietary fiber (3). Under these circumstances, supplementation is needed.

Another important consideration is the water loss that occurs with the Atkins plan. In the early stages of the diet, you can expect a substantial loss in water (due to glycogen depletion; for every gram of glycogen you store, you also store 2.8–3.5 grams of water). The belief that there are some magical metabolic advantages to this diet is a fallacy that isn't supported by scientific data. Long-term weight loss happens because of calorie reduction. Numerous studies have indicated a big reduction of calories (below maintenance requirements) when following low carbohydrate diets.

The newest version of the diet promotes the intake of high fiber foods, which is a good thing (in most cases). Many people who have followed the diet now realize dietary fat isn't the sole reason people are fat nor is it the evil often promoted by low fat diet advocates.

In conclusion, if you can stick to the food recommendations and function well while following a low carbohydrate diet, the Atkins diet may be for you. Athletes using the Atkins’ diet should be highly cautious as performance may suffer (decreased performance happens generally in glycolytic athletes—those whose primary fuel source is stored glucose or glycogen). Any diet that results in weight loss generally enhances health markers. If you are following the Atkins plan and aren't dropping weight, pay close attention to lipid (cholesterol, triglyceride) levels. Numerous studies have shown that in the absence of weight loss, ketogenic diets (low carbohydrate diets) may be detrimental to blood lipids levels. On the other hand, ketogenic diets that result in weight loss are good for blood lipid levels. If you are gaining weight, reduce calories further or try something different.


  1. Aragon A (2007) Girth Control: the science of fat loss and weight gain. 1st ed. Alan Aragon.
  2. Atkins RC (1992) Dr. Atkins New Diet Revolution. New York: Avon Books, Inc.
  3. Freedman MR, et al (2001) Popular Diets: A Scientific Review. Obesity Research 9(1).
  4. Goodwin K. Atkins Diet: A Comprehensive analysis. The Diet Channel. At: #. Accessed: November 27, 2010.
  5. Hale J (2007) Knowledge and Nonsense: the science of nutrition and exercise. MaxCondition Publishing.
  6. New SA, et al (1997) Nutritional influence on bone mineral density: a cross-sectional study in pre-menopausal women. AM J Clin Nutr 65:1831–39.