According to the United States Surgeon General's Report on Nutrition and Health, fad diets include "the promotion for profit of special foods, products, processes, or appliances with false or misleading health or therapeutic claims."
Fad diets are generally used by consumers to shed a great amount of weight in a short period of time. They are usually based on the erroneous belief that a particular food or food component can cause rapid weight loss or cure a disease. Another tenet of fad diets is that certain foods are harmful and therefore should be avoided completely.
Fad diets usually result in a short-term weight loss—but most people gain the weight back after discontinuing the diet. The American Dietetic Association (ADA) has established a few guidelines to help evaluate the reliability of fad diets. They suggest that consumers avoid diets that claim weight loss can be achieved in a very short period of time; that imply that weight can be lost without any physical activity; or that rely on undocumented studies.
The most reliable way to lose weight safely and maintain weight loss is by eating a variety of foods and exercising consistently. Dieters who follow the guidelines set by the ADA, which include eating a variety of foods, balancing food intake with exercise, choosing a variety of fruits and vegetables, limiting saturated fat and cholesterol, and keeping total fat intake to a moderate level will have a healthy lifestyle—which when adhered to will ultimately aid in weight management. Many fad diets, for example, counsel dieters to eliminate certain foods or to eat one specific food for a long period of time. This approach does not promote healthy eating habits, nor does it augur well for permanent weight loss.
Fad diets have been promoted and used for many years. Some of the most popular fad diets today include high-protein diets, liquid diets, the grapefruit diet, food-combining diets, the cabbage diet, and a variety of diet pills.
High-protein diets began in the 1970s, based on the theory that too many carbohydrates in the diet interfere with the body's ability to burn fat. This diet encourages the consumption of large quantities of protein-rich foods such as meat, fish, shellfish, eggs, poultry, and cheese. Some popular high-protein diets include the Atkins diet, the Zone, and the protein-power diet.
While liquid diets are often convenient and easy to prepare, the transition back to solid foods can lead to weight gain.
Ketones—Acidic by-products of fat breakdown that alter the acid-base balance of the blood.
Nitrogen—A component of protein that is highly toxic when too much protein is consumed and the kidneys are unable to process and excrete it.
Saturated fat—Type of fat that is usually solid at room temperature.
for two meals and a snack during the day. Health shakes normally provide about 200 calories each, with the last meal of the day consisting of low-fat, nutrient-dense foods that offer another 600 calories.
The grapefruit diet
Grapefruit is essentially a fat-free, low-calorie, low-sodium food that is high in vitamin C, beta-carotene, and fiber. The grapefruit diet began in the 1930s, when the Hollywood diet made its debut. This regimen consisted of a few vegetables, a small amount of protein, and a grapefruit (which was thought to possess a fat-burning enzyme) at every meal. It is usually followed for a period of three weeks. The diet provides only 800 calories per day, which makes the possibility of weight loss very likely.
Food-combining diets are based on the mistaken idea that carbohydrates and proteins should not be consumed at the same time, and that fruit should not be eaten with proteins or carbohydrates. There are a variety of food-combining diets, but most recommend eating large portions of fruit for the first several days, which is thought to burn up calories before the body metabolizes them. A few carbohydrates and very little protein are then added during the last part of the diet.
The cabbage soup diet
The cabbage soup diet is a more recent fad that results in a significant amount of weight loss from shedding water. It consists of eating cabbage soup, which contains cabbage, onions, green peppers, tomatoes, celery, and water, for one week. Each day as much soup is eaten as desired, along with one specified food, which can also be eaten in unlimited amounts. The cabbage does not burn fat, but it does promote a sense of fullness.
These compounds may help start weight loss, but their benefit usually plateaus after a year, after which their effect declines. In addition, they can strain the heart by increasing blood pressure and heart rate.
This type of diet does slow the rate of carbohydrate absorption, which helps control blood sugar levels and promotes a feeling of fullness. However, high-protein diets also tend to be high in saturated fat and cholesterol, which can contribute to heart disease. When high-protein diets are followed for a very for a long time, they cause the body to burn excessive amounts of fat for fuel, This releases chemicals called ketones into the bloodstream, causing dizziness, headaches, nausea, and bad breath. Too much protein also places extra work on the kidneys, forcing them to work harder to excrete the nitrogen present in protein. They also create extra work for the liver, which must break the protein compounds into individual amino acids.
While this diet is very low in calories and almost guaranteed to result in some weight loos, limiting dieters to such a small amount of food is very restrictive and eliminates such vital nutrients as calcium, iron, folic acid, and other vitamins.
Since fruits are so low in calories, it is possible to lose a significant amount of weight in a short period of time. Due to the protein restriction, however, muscle and organ tissues may be broken down for energy.
This diet can cause bloating, gas, nausea, and light-headedness after a few days. It is not recommended by health professionals; but since soup is usually a low-calorie food, eating this soup in conjunction with a healthy diet consisting of a variety of foods can facilitate a healthy weight loss.
While each of these diets may result in a temporary weight loss, most are unhealthful and deprive the body of needed nutrients. Most dieters regain the weight after they stop following the diet.
Health care team roles
The American Dietetic Association, the United States Surgeon General, the National Academy of Sciences, and the American Heart Association all employ qualified professionals who can educate consumers on the advantages and disadvantages of fad diets. While certain components of fad diets may aid in weight management when used in conjunction with a healthy lifestyle, it is not recommended that they be used alone. People must understand that behavior modification is the most effective way to lose weight and keep it off. Through physical exercise, eating a variety of nutritious foods, and consciously changing eating habits, weight loss can be achieved and maintained.
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Lisa M. Gourley