By Brenda Davis, RD

The Atkins Diet has become one of the most popular weight loss diets of all times. Almost everyone has heard of the diet, and most of us know several people who are on it.

The Atkins Diet encourages low carbohydrate intake - no more than 20 grams a day during induction. After induction, 5 grams of carbohydrates are added each week or two until the person stops losing weight. Most people end up in the 35-40 grams a day range. The diet is very high in fat (50-66% of calories) and very high in protein (about 25-35% of calories).

To put this into perspective, it is important to understand that all plant foods contain carbohydrates. For example, a cup of rice or beans or a baked potato contains 40-50 grams of carbohydrates. A cup of cereal, two slices of bread or ¾ cup of pasta contains 20-30 grams of carbohydrates. Even a small fruit contains 10-15 grams of carbohydrates. Thus, on an Atkins regime, whole plant foods are severely limited. What's left? Mainly meat, poultry, fish, and fatty dairy products such as butter and cheese (fluid milk is higher in carbohydrates at 12-14 grams per cup).

The medical community has frowned on the Atkins Diet for many years, although it has more recently received some favorable press. Scientific studies report that the Atkins Diet produced more successful results than the conventional "low fat" weight loss diets, finding greater weight loss, as well as improved blood cholesterol and triglyceride levels. However, the studies were small and of short duration, thus long-term consequences were not observed. There is no doubt that the Atkins Diet can lead to weight loss. But, as Dr. Dean Ornish pointed out, so can chemotherapy, but that doesn't mean it is good for you.

What gives? If plant-based diets are really best for human health, why the apparent success of Atkins?

The reason for the short-term success of the program is that the diet is controlled in calories (weight loss itself will improve blood cholesterol and triglyceride levels). It also significantly reduces two damaging components, refined carbohydrates and trans fatty acids, and increases one protective dietary component, omega-3 fatty acids.

Refined carbohydrates (sugars and starches) are found in almost all processed foods in the form of sugars, syrups and white flour. The problem with refined carbohydrates such a sugar and white flour is that they have been robbed of almost everything of value to human health, such as fiber, phytochemicals and antioxidant nutrients. When these foods make up a significant portion of the diet, they can be highly damaging to human health, increasing triglycerides, decreasing protective HDL-cholesterol, and increasing risk of gastro-intestinal disorders.

What's worse is we take these refined carbohydrates and add salt and hydrogenated fat to them (in baked goods, snack foods, fast foods, margarine, crackers, etc.). Hydrogenated fat is a type of fat produced by adding hydrogen to a liquid oil, turning it into a solid fat. In the process we create trans fatty acids. These are possibly the most damaging fats in the diet. The World Health Organization recommends an absolute maximum of 1% of calories from trans fatty acids. (That's 2.2 grams in a 2000 calorie diet. We get 5 grams in a medium order of fries.)

What most Atkins followers don't seem to understand is that not all carbohydrates are equal. In fact, the lowest rates of chronic disease in the world are in countries with the highest carbohydrate intakes. The critical point is that when carbohydrates come from whole foods, they are consistently associated with health benefits. When they are refined (when all the beneficial components are removed), they have detrimental effects on health. Indeed, there are volumes of research that confirms that diets based on whole plant foods are the most protective diets on the planet. The Atkins group misses this crucial point.

There are two primary groups of foods that have been demonstrated to have negative consequences for health when consumed in excess - processed foods (including most "fast foods") and animal foods (especially high-fat animal foods). Animal foods are our primary sources of saturated fat and cholesterol, both of which have been demonstrated to increase risk of heart disease, type-2 diabetes, and several forms of cancer. They are also our most concentrated source of ingested environmental contaminants, such as heavy metals (mercury, lead and cadmium) and industrial pollutants such as PCB, DDT and dioxins.

The dietary components most strongly linked to disease prevention and health promotion are components that are concentrated in plant foods - fiber, phytochemicals, antioxidant nutrients, and healthful mono and polyunsaturated fats, including essential fatty acids. Fiber and phytochemicals are found only in plant foods.

The Atkins Diet is primarily animal foods. Eating a diet that is mainly animal foods is risky, to say the least. There is a good chance you will increase your long-term risk of heart disease and certain types of cancer, but that is only the beginning. Carbohydrates are the body's primary fuel source, and when the body is lacking carbohydrates, it makes them from fat. When fat is broken down, one of the by-products is ketones, an acidic waste product that builds up in the bloodstream leading to ketosis. Keeping the body in ketosis is stressful to the kidneys and liver. It also causes urinary calcium losses, increasing risk of osteoporosis. This is a huge problem, considering the high rates of osteoporosis we currently face in the western world.

High protein diets can also foster the growth of pathogenic organisms in the intestine, which can injure the intestinal wall and lead to the "leaky gut syndrome" - a condition of increased intestinal permeability, which allows injurious fragments of antigenic food proteins and bacterial breakdown products to leak into the bloodstream. These foreign, inflammation-inciting substances can, in turn, exacerbate arthritis, lupus and other autoimmune diseases in tissues throughout the body.

Finally, the real cost of the Atkins Diet, goes far beyond human health. The Atkins Diet means expanding intensive animal agriculture, with devastating consequences for ecosystems - pollution to water, soil and air; increasing desertification, deforestation, and species extinction. Needless to say, it also means pain and suffering for an even greater number of animals.

By consuming a high-fiber, whole foods, plant-based diet, we can enjoy the greatest possible benefits for disease risk reduction, weight loss and general well-being. The bonus is that in so doing, we protect the environment, and we promote compassion for all living things.

Brenda Davis is a registered dietitian and is a past chair of the Vegetarian Nutrition Dietetic Practice Group of the American Dietetic Association. Brenda is the author of five books - the best-sellers Becoming Vegetarian (1995) and Becoming Vegan (2000), Dairy-free and Delicious (2001), and the newly released, Defeating Diabetes (2003) and The New Becoming Vegetarian (2003), all published by The Book Publishing Company (Summertown, TN). http://www.hope-care.org/mainpage.htm