Low carbohydrate diet
Related Terms
Atkins, Atkins nutritional approach, carbohydrates, fad diet, food pyramid, high protein diet, low carbohydrate diet, low carb diet, Robert Atkins, South Beach diet?.
Background
A low carbohydrate diet is one in which daily consumption of carbohydrates is limited or reduced, and fats and protein are increased. There are several types of low carbohydrate diets, but the most widely used low carbohydrate diet is the one advocated by Dr. Robert Atkins. The Atkins diet proposes that, in order to lose weight, one should adopt an eating style that radically departs from the Food and Drug Administration's (FDA) food pyramid. It proposes the elimination of most carbohydrates as a source of energy; in the place of carbohydrates, the diet advocates the significantly increased consumption of fats, including trans fats and hydrogenated oils.
Carbohydrates are the most common source of energy in the American diet, and they occupy the bottom of the FDA food pyramid. Bran, cereal, bread, potatoes, and pasta all contain high amounts of carbohydrates. Eating carbohydrates result in the body's secretion of insulin. Insulin is a substance produced in the body to regulate the metabolism of carbohydrates.
In the 1960s, Atkins created what is known today as the "Atkins diet" after reading an article in a scientific journal. The cardiologist claimed to have treated thousands of obese patients, as well as his own obesity, after following the new diet plan. In 1972, Atkins published Dr. Atkins' Diet Revolution. In 2001, Atkins published an updated version of this book. In 2003 and 2004, the so-called "Atkins Nutritional Approach" became popular nationwide as Americans flocked to the idea of unlimited meat consumption.
The Atkins diet does not require dieters to count calories, weigh in, or record foods eaten. Despite the apparent simplicity of this diet, experts have recently found long-term health risks, including type 2 diabetes, kidney impairment and other serious medical problems. Some of the recent popularity in the Atkins diet was based on the continuing misconception of the fad diets that one could lose weight and achieve physical fitness without exercising or controlling food portions.
The Atkins diet can be easily confused with South Beach diet. They both have the initial two weeks of restricting carbohydrates. However, after this initial phase, they differ in two significant ways. Under the South Beach diet, "good" carbohydrates are not discouraged, and "bad" fats are. The Atkins diet does not recommend any carbohydrate consumption. The safety and long-term efficacy of Atkins is a subject of debate in the medical community.
The role that the Atkins diet may or not play in alleviating long-term trends of obesity and other metabolism related conditions requires further investigation.
Theory / Evidence
Atkins proposed that the significant increase in insulin-producing foods, especially refined carbohydrates, were the primary cause of increases in American metabolic disorders, including obesity. The consumption of carbohydrates results in the secretion of insulin. Atkins theorized that most Americans suffer from what he termed "hyperinsulinism," a chronic state of high levels of insulin in the body.
The human body derives energy from food via three pathways. Usually, the body burns glucose from carbohydrates as the source of energy. During the introduction period of the Atkins diet, the body is forced to burn fat as the primary source of energy. The body quickly enters what is known as ketosis as a result. Ketosis requires more steps, and thus, offers less energy than the energy pathway of carbohydrate metabolism. Further steps include a small amount of carbohydrates into the diet. These carbohydrates are important because the brain can only derive energy from glucose. For this reason, avoidance of carbohydrates after the introduction phase may result in ketoacidosis, a serious condition resulting from the absence of glucose for prolonged periods of time.
The diet is based on the theory that overweight people eat too many carbohydrates. Bodies burn both fat and carbohydrates for energy, but carbohydrates are used first. By drastically reducing carbohydrate intake and increasing protein and fat intake the body will, in theory, naturally lose weight by burning stored body fat more efficiently.
An article in the journal Obesity Research (2001) found that the drastic weight loss, which occurs at the start of the Atkins diet does not continue after about six months. The study found that individuals on the Atkins diet experienced long-term weight loss results similar to individuals on weight loss plans with similar regimens of calories.
A study in the Journal of the American Medical Association found that most individuals on the Atkins diet did not comply with the eating for the year length of the study duration. In addition, those who initially lost weight on Atkins did not sustain their weight loss or lowered risk of diabetes if they failed to abide by the plan.
Some experts have attributed the success of the Atkins diet to a significantly reduced intake of calories, rather than changes in the body's metabolism. However, the way that the Atkins diet changes the body's metabolism is unknown.
Author information
This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
Bibliography
A critique of low-carbohydrate ketogenic weight reduction regimens. A review of Dr. Atkins' diet revolution. JAMA 6-4-1973;224(10):1415-1419.
Atkins R. Dr. Atkins' Diet Revoution. New York: Bantam, 1979.
Atkins R. Dr. Atkins' New Diet Revolution. New York: Avon, 2001.
Dansinger ML, Gleason JA, Griffith JL, et al. Comparison of the Atkins, Ornish, Weight Watchers, and Zone diets for weight loss and heart disease risk reduction: a randomized trial. JAMA. 2005 Jan 5;293(1):43-53.
Food and Drug Administration: Food Pyramid. 17 June 2006.
Freedman MR, King J, Kennedy E. Popular diets: a scientific review. Obes Res. 2001 Mar;9 Suppl 1:1S-40S.
Diet outline
Despite the common public perception that the Atkins diet permits an unlimited consumption of greasy foods, it is actually recommended that dieters consume primarily lean meats, such as seafood and poultry.
Like many diet plans, the Atkins diet requires regular consumption of nutritional supplements, such as a multivitamin pill, and adherence to a regular exercise plan. The Atkins diet does not recommend individuals adopt the eating plan unless they abide by the nutritional supplements and exercise routine. A qualified healthcare professional should be consulted before beginning any new diet.
Under the Atkins diet, dieters are recommended to stop any unnecessary medications. Any changes to medication should be discussed with a qualified healthcare professional. Diuretics, and, to a lesser extent, other cardiovascular medications and diabetes medications, including insulin, when combined with this diet may produce a dangerous overdose. Psychotropic drugs, phenothiazines and anti-depressants, including Prozac, tranquilizers, lithium and similar drugs, may cause metabolic resistance to the diet. Hormones such as estrogen, prednisone, other steroids, and the anti-arthritic drugs, especially NSAIDS, can cause weight gain / prevent weight loss. For persons metabolically resistant, any medications may aggravate the condition.
Induction period (first two weeks): Dieters are permitted to eat no more than 20g of carbohydrates per day with a diet consisting of nearly unlimited meats, poultry, seafood, eggs, cheeses, oils, butter, margarine, bacon, and sausages. The 20g carbohydrate limit is generally derived from trace amounts of carbohydrates in sauces, dressings, cheeses and a couple cups of lettuce greens or vegetables daily. During these two weeks, participants are not allowed to have any milk, fruits, grains, cereals, breads, or "high glycemic index" vegetables such as potatoes, peas, corn, and carrots.
Ongoing weight loss period: Dieters begin adding about 5 more grams of carbohydrates to their diet weekly. This phase continues until the dieter is within 10 pounds of their target weight.
Pre-maintenance period: At this stage, dieters typically have only 5-10 pounds left to lose, and can increase carbohydrate intake by 10 grams each day for a week at a time.
Maintenance period: Generally, dieters consume no more than 90g of carbohydrates daily in the maintenance phase.
Forbes Magazine found the Atkins diet to be one of the five most expensive food diets available. According to this report, the Atkins diet costs, on average, $100.52 per week. This number is 84.6% higher than the $54.44 an average American spends per week on food.
Though a cardiologist wrote the Atkins books, there is currently no licensure or process for health care practitioners who advocate the Atkins diet to receive certification.