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Atkins Nutritional Approach

The Atkins Nutritional Approach, popularly known as the Atkins Diet or just Atkins, is a way of looking at nutrition, perhaps the most marketed and well-known of the low-carbohydrate diets. It was popularized by Dr. Robert Atkins (1930-2003) in a series of books, starting with Dr. Atkins' Diet Revolution in 1972. There are many outspoken advocates and critics of the diet, and in his revised book, Dr. Atkins' New Diet Revolution, Atkins updated some of his ideas, but remained faithful to the original concepts.

The Atkins franchise (i.e., the business formed to provide products serving people "doing Atkins") had been highly successful due to the popularity of the food plan, and is considered the iconic and driving entity of the larger "low-carb craze." However, various factors have led to its dwindling in success, and the company Atkins Nutritionals of Ronkonkoma, New York, founded by Dr. Atkins in 1989 filed for bankruptcy in July of 2005.

While once considered popular, it had likewise been controversial for its claims regarding high-protein and high-fat diets. The Atkins logo is highly visible through licensed-proprietary branding for food products, and related merchandise. While many viewed Atkins critically for his claims, regimented plans, and profit-making franchise, he is nevertheless credited with popularizing the availability of healthier low-carb foods in the United States and abroad.

Nature of the diet

The Atkins represents a radical departure from prevailing theories. He claimed there are two main unrecognized factors about Western eating habits, arguing firstly that the main cause of obesity is eating refined carbohydrates particularly sugar, flour, and high-fructose corn syrups; and secondly that saturated fat is overrated as a nutritional problem, and that only trans fats from sources such as hydrogenated oils need to be avoided. Consequently, Dr. Atkins rejects the advice of the food pyramid, instead asserting that the tremendous increase in refined carbohydrates is responsible for the rise in metabolic disorders of the 20th century, and that the focus on the detrimental effects of dietary fat has actually contributed to the obesity problem by increasing the proportion of insulin-inducing foods in the diet.

Dr. Atkins argued that many eating disorders are the result of hyperinsulinism, or excessive secretion of insulin which comes through eating too many carbohydrates. According to Dr. Atkins, this causes food cravings and unstable blood sugar levels, which can cause mood swings, depression, and sleeping problems. He claimed that his diet stabilizes insulin and blood sugar levels, eliminating cravings and often reducing appetite.

While most of the emphasis in Atkins is on the diet, nutritional supplements and exercise are considered equally important elements.

Atkins involves restriction of the intake of carbohydrates in order to switch the body's metabolism from burning glucose to burning fat (chiefly stored fat). This process (called lipolysis) begins when the body enters the state of ketosis as a consequence of running out of carbohydrates to burn. Although Dr. Atkins claimed that ketosis helped the body burn fat more easily, nutritionists are quick to point out that the body will burn stored fat for energy whenever the food energy taken in is less than that burned.

Atkins restricts "net carbs", or carbs that have an effect on blood sugar. Net carbohydrates can be calculated from a food source by subtracting sugar alcohols and fiber (which are shown to have a negligible effect on blood sugar levels) from total carbohydrates. Sugar alcohols need to be treated with caution, because while they may be slower to convert to glucose they can be a significant source of glycemic load and can stall weight loss.

Preferred foods in all categories are whole, unprocessed foods with a low glycemic load.


There are four phases of the Atkins diet:


The Induction phase is the first, and most restrictive phase of the Atkins Nutritional Approach. It is intended to cause the body to quickly enter a state of ketosis. Carbohydrate intake is limited to 20 net grams per day. The allowed foods include a liberal amount of most meats, a good bit of cheese and cream, two cups of salad, and one cup of other vegetables. Caffeine and alcoholic beverages are not allowed.

The Induction Phase is usually when many see the most significant weight loss - reports of losses up to six or eight pounds (3 or 4 kg) per week are not uncommon.

Atkins suggests the use of KetoStix, small chemically reactive strips used by diabetics. These let the dieter monitor when they enter the ketosis, or fat burning, phase.

Ongoing weight loss

The Ongoing Weight Loss (OWL) phase of Atkins consists of an increase in carbohydrate intake, but remaining at levels where weight loss occurs. Carb intake increases by 5 grams of carbs per day each week. A goal in OWL is to find the "Critical Carbohydrate Level for Losing". The OWL phase lasts until weight is within 10 pounds (4.5 kg) of the target weight.


Carbohydrate intake is increased again, and the key of goal in this phase is to find the "Critical Carbohydrate Level for Maintenance", this the maximum number of carbohydrates you can eat each day without gaining weight.

Lifetime maintenance

This phase is intended to carry on the habits acquired in the previous phases, and avoid the common end-of-diet mindset that can return people to their previous habits and previous weight. Whole, unprocessed food choices are emphasised, with the option to drop back to an earlier phase if you begin to gain weight.


The Atkins Nutritional Approach gained widespread popularity in 2003 and 2004. At the height of its popularity one in eleven adults were on the diet. This large following was blamed for large declines in the sales of carb heavy foods like pasta and rice (sales were down 8.2 and 4.6 percent respectively in 2003). The diet's success were even blamed for a decline in Krispy Kreme sales. Trying to capitalize on the "low-carb craze" many companies released special product lines which were low in carbohydrates. Coca-Cola released C2 and Pepsi-Cola created Pepsi Edge (which is scheduled to be discontinued later in 2005.

When Robert Atkins died in 2003 the nutritional plan suffered from rumors and allegations that he had died from a heart condition brought about because of his weight. Surveys conducted by Forbes found that the Atkins Nutritional Approach is one of the most expensive diet plans. On July 31, 2005, the Atkins Nutritional company filed for Chapter 11 bankruptcy protection after the percentage of adults on the diet declined to two percent and sales of Atkins brand product fell steeply in the second half of 2004.


Low-carbohydrate diets have been the subject of heated debate in medical circles for three decades [7]. They are still controversial and only recently has any serious research supported some aspects of Atkins' claims, especially for short-term weight-loss (6 months or less).

But many in the scientific community also raise serious concerns:

* The National Weight Control Registry, funded by the National Institutes of Health (NIH) tracked the habits of successful dieters over a longer term, 10 years. Despite this diet's overwhelming popularity compared to other diets, of the 5,000 Americans confirmed to have lost an average of 70 pounds (32 kg) and able to prove they have kept it off for at least 6 years of the decade of NIH’s data-keeping, less than 1% were confirmed to be Atkins adherents.

* Even in studies only one year long, this diet can fail to produce the greater weight-loss which is claimed to come from factors other than calorie-reduction such as ketosis: It was compared to dieters on Dean Ornish’s diet, Weight Watchers, and The Zone diet for 1 year. The Atkins Diet came last in terms of weight lost at the end of the year. (Dansinger, M.L., Gleason, J. L., Griffith, J.L., et al., "One Year Effectiveness of the Atkins, Ornish, Weight Watchers, and Zone Diets in Decreasing Body Weight and Heart Disease Risk", Presented at the American Heart Association Scientific Sessions 12 November 2003 in Orlando, Florida.)

* The May 2004 Annals of Internal Medicine study showed that Atkins Dieters had significantly more diarrhea, general weakness, rashes and muscle cramps. now suggests a fiber supplement.

* Also, acidity from the typically high protein intake can cause Osteoporosis (Feskanich D, Willett WC, Stampfer MJ, Colditz GA. Milk, dietary calcium, and bone fractures in women: a 12-year prospective study. Amer Jrnl Public Health 1997;87:992-7. See also follow-up in February, 2003 issue of the American Journal of Clinical Nutrition (Vol. 77, No. 2, 504-511); this includes 72,000+ people and 18 years of data. Cumming RG, Klineberg RJ. Case-control study of risk factors for hip fractures in the elderly. Amer Jrnl Epidemiology 1994;139:493-503.

With its emphasis on fatty foods, the Atkins diet has generally been considered by most medical and nutritional experts to be unsound. It also violates the food pyramid, which states that amounts of carbohydrates, protein and fats (in that order) must be regularly consumed to stay healthy. Some experts have even suggested Atkins' plan is quackery. Among those criticizing the healthiness of his diet, if not also skeptical of the claims of greater weight-loss than other, safer diets, are such reputable organizations as:

a. “...the Atkins diet, as recommended, poses a serious threat to health.” --Chair of the American Medical Association's Council on Food and Nutrition, testimony to Congress

b. "unhealthy and can be dangerous." --C. Everett Koop (Shape Up America! news release, 29 December 2003)

c. "a nightmare of a diet." --Journal of the American Dietetic Association 102 (2002): p.260

d. Also condemned by National Institutes of Health in NIH Publ. No. 94-3700, 1993.

e. Condemned by ACS in American Cancer Society; Weighing In on Low Carb Diets, 2004.

f. Condemned by the American Kidney Fund in American Kidney Fund news release, 25 April 2002.

g. Condemned by American Heart Association in Circulation 104 (2001): p.1869.

h. Condemned by Johns Hopkins in Diabetes 2004. Johns Hopkins University White Paper, 2004

i. Condemned by the American College of Sports Medicine in Medicine and Science in Sports and Exercise 33 (2001): p.2145.

j. Expressing a general sentiment was the conclusion: “runs counter to all the current evidence-based dietary recommendations.” --Journal of the American College of Cardiology 43 (2004): p.725

Opponents of the diet also point out that the initial weight loss upon starting the diet is a phenomenon common with most diets, and is due to reduction in stored glycogen and related water in muscles, not fat loss. They claim that no evidence has surfaced that any diet will cause weight loss unless it reduces food energy below the maintenance level, and reports have indicated that successful weight loss due to the Atkins diet may be the result of less food energy being consumed by the dieter, rather than the lack of carbohydrates. [8] They further point out that weight loss on fad diets, which typically restrict or prohibit certain foods, is often due to the fact that the dieter has less food choices available. Also, a diet of low-carb foods may quickly become dull to many people, meaning that their appetite is somewhat naturally suppressed as they become hungry for carbs, but the dieter either has none handy or resists this hunger.

On May 27, 2004, Jody Gorran, a 53-year-old Florida businessman with a family history of heart disease, filed a lawsuit against Atkins Nutritionals, Inc. and the estate of Dr. Robert Atkins, claiming that the Atkins diet regimen caused severe heart disease, making it necessary for him to undergo angioplasty. As of 28 May, he has been seeking a court injunction banning Atkins Nutritionals from marketing its products without a warning of potential health risks, and asking for compensatory damages.

Dr. Robert Eckel of the American Heart Association says that high-protein, low-carbohydrate diets put people at risk for heart disease.

The Physicians Committee for Responsible Medicine, which is opposed to the Atkins diet, has noted that in East Asian countries such as Thailand or Japan, the average person's diet consists of mainly carbohydrates such as rice and noodles, yet these Asians have very low rates of obesity. The average Asian person is also thinner and slimmer than the average Westerner. This example seems to contradict the Atkin's claim that low-carbohydrate diets help to lose weight.

There's also the question of how to produce food in a manner sustainable for the environment, which seems to be harder for Atkins type food (meat) than grain and beans.

Views in favor of the diet

When the Atkins diet was introduced in the 1970s, it was immediately attacked by existing experts, who claimed it was unhealthy and would fail. Those claims persist today, even though there are now studies indicating the contrary:

* "The low-carbohydrate diet produced a greater weight loss...and greater improvement in some risk factors for coronary heart disease" --New England Journal Of Medicine, Volume 348:2082-2090, 22 May 2003, Number 21
* "better participant retention and greater weight loss...greater decreases in serum triglyceride levels" --Annals Of Internal Medicine, 18 May 2004 | Volume 140 Issue 10 | Pages 769-777
* "Diets high in fat do not appear to cause excess body fat, and reductions in fat will not be a solution." --American Journal Of Medicine, Volume 113, Issue 9, Supplement 2, 30 December 2002, Pages 47-59
* "sustained weight loss" --American Journal of Medicine, Volume 113, Issue 1, July 2002, Pages 30-36
* "When carbohydrates were restricted, study subjects spontaneously reduced their caloric intake to a level appropriate for their height, did not compensate by eating more protein or fat, and lost weight. We concluded that excessive overeating had been fueled by carbohydrates." "In addition to the calorie reduction and weight loss, subjects experienced markedly improved glucose levels and insulin sensitivity, as well as lower triglycerides and cholesterol." This is not a controlled study in that there was no control group; it merely observed the effect of putting ten obese diabetics on the Atkins diet; this is "the only study of the Atkins diet to have been conducted in the strictly controlled environment of a clinical research center where every calorie eaten and spent was measured." --Annals of Internal Medicine, 15 March 2005

Many of these represent scientifically controlled studies, published in peer-reviewed journals. Proponents of the Atkins diet feel much of the criticism leveled at the diet comes from statements and opinions of individuals and associations, rather than from controlled and reviewed studies. Advocates of the diet dispute criticisms based on the fact that a low-carb diet is likely to be high-fat and allegations that fat, especially saturated fat, is harmful. Atkins backers maintain that, aside from trans fat, saturated fat is not harmful and is actually necessary in diet. Proponents cite Gary Taubes who, in a 2001 article in Science, 291 (5513): 2536, claims that the oft-cited "consensus" opinion against saturated fats derives from political rather than scientific motives.

The original recommendations for low-fat diets were based on the idea that, yes, the studies had not been done to prove fat harmful, but maybe it was harmful (for example, saturated fat in diet was associated in some studies with high cholesterol levels which was associated in some studies with heart disease), and allegedly there was no harm in reducing fat, therefore it should be reduced; millions of lives might be lost if we waited for scientific proof.

However, when fat is reduced in a diet, the practical consequence is that people will substitute carbohydrates. Carbohydrates, especially highly-processed, quickly-digested carbohydrates, cause a blood sugar spike, stimulating insulin production and all the consequences of that, quite possibly resulting in weight gain, which is itself a major cardiac risk factor. As was pointed out at the time the original low-fat recommendations were being worked out, shifting dietary composition toward carbohydrates and away from fat affects many different metabolic systems in the body; making such a shift without strong scientific evidence effectively subjected a whole population to an uncontrolled experiment; only now are the results of this experiment starting to be widely examined, and many are concluding that recommending low-fat diets was a very bad idea. It's not just the cardiologist, Dr. Atkins, but also renowned cardiologist Dr. Agatston ("South Beach Diet") and many others.

Critics of the Atkins diet may focus particularly on Atkins, or on low-carb dieting in general. Proponents claim that critics to consider that people are built differently, and as with any diet, the Atkins may not be effective for some people. For some people, a low-fat diet may work as well as a low-carb diet, perhaps better. But for many people, it seems, a low-carb diet may be more effective, and there is accumulating research confirming this.

Opponents of the Atkins diet tend to claim that weight is regained when dieting stops. However, this is true of all diets, not just low-carb diets. It is unfair to single out the Atkins or any low-carb diet for this factor. The crucial issue is the sustainability of the diet in its Maintenance phase. In the context of widespread propaganda against fat, many people, even those who try the Atkins diet or other low-carb diet, try to make it low-fat, which apparently does not work. The fat is a crucial part of Atkins, for fat is satisfying, it sates.

For years, opponents of the Atkins diet claimed that (1) it would not work, it was preposterous, eating all that fat would make people fat, and (2) it would seriously increase cardiac risk. Yet, when studies are finally done to see what low-carb/high-fat diets actually do, they are at worst as effective as the recommended low-fat diets, and they do not, in fact, increase cardiac risk factors; indeed, overall, they lower them. So then the critics defend their low-fat position by noting, correctly, that the new studies were small. Yet the studies on which the low-fat gospel was based were also small, and less definitive. In the end, no study has shown that cardiac disease has been reduced by promoting low-fat diets, and there is evidence to the contrary.

Criticism of the diet often focuses on the safety of inducing ketosis, which is one of the body's natural processes for the metabolism of body fat often during sleep. It is biologically natural to burn fat - that's why we store it. Ketosis should not be confused with ketoacidosis, a serious medical condition seen in diabetics and alcoholics.

Low-fat diets are not automatically healthy ones. Traditional, high-fat French cooking has led to a much lower incidence of obesity, morbid obesity and chronic heart disease than in the high-sugar American diet, despite overall energy intake and exercise levels being the same.

The 22 May 2003, issue of the New England Journal of Medicine published two scientific, randomized studies comparing standard low-fat diets to low-carbohydrate diets such as the Atkins Diet. In both studies, subjects lost more weight on the low-carbohydrate plans.

A research study carried out by the Weight and Eating Disorders Program at the University of Pennsylvania, reported in May 2003 that the Atkins diet raised levels of HDL (or "good") cholesterol by an average of 11% and reduced the amount of triglycerides in the bloodstream by 17%. This counters one of the chief criticisms of Atkins' approach, which is that cholesterol is raised by eating fatty foods and meat.

In the study, conventional dieters' HDL cholesterol raised by only 1.6% while their triglyceride levels did not improve significantly. Weight loss was also statistically greater in the Atkins dieters after three and six months compared with the conventional dieters (although this did not remain statistically significant after a year). The study followed the diets of 63 obese men and women. (See New Scientist, 21 May 2003.)

Misconceptions about the diet

Many people incorrectly believe that the Atkins Diet promotes eating unlimited amounts of fatty meats and cheeses. In fact, while certain foods are allowed in unlimited quantities (i.e., are limited only by appetite), the Atkins Diet is very specific in recommending lean meats, such as seafood and poultry. This is a key point of clarification that Dr. Atkins addressed in the more recent revisions of his book.

Some criticism of the diet seems to be based on a confusion between ketosis and ketoacidosis. Ketosis is short for Benign Dietary Ketosis, which is a normal metabolic process that results when glucose is not available as a source of energy. The body then burns mostly fat, both directly and through conversion to ketones which make the energy of fat available in water soluble form. Ketoacidosis is a metabolic crisis due to the inability to utilize glucose because of a lack of insulin and in which there is an abnormal accumulation of ketones exacerbated by severe dehydration as the kidneys spill the useless glucose, losing water in the process. This occurs in diabetics and in a related form in alcoholics.

Another common misconception arises from confusion between the Induction Phase and rest of the diet. The first two weeks of the Atkins Diet are strict, with only 20g of carbohydrates permitted per day. The plan is clear that dieters should not ordinarily continue past the 2-week Induction Phase without slowly raising their daily carbohydrate count. Once the weight-loss goal is reached, carbohydrate levels are raised even further, though still significantly below USDA norms, and still within the definition of ketosis.

The Induction Phase is also known for its comparatively lower intake of dietary fiber, and this is often misconstrued as characteristic of the diet as a whole. It is often misstated that those on the diet do not consume enough vegetables and fruits. However those who follow it properly should not face this problem as even the Induction Phase allows for adequate amounts of dark green leafy vegetables, for example.

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