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A Warning To Atkins Dieters

Some doctors are raising a red flag about the safety of the popular, high protein, low-carb Atkins diet.

Dr. Neal Barnard, a representative for the Physicians Committee for Responsible Medicine (PCRM), explains on The Early Show that new survey and data of previously unreported health problems raises questions about the safety of the Atkins Diet and other high-protein, low-carb weight-loss plans.

He says," This morning, we're reporting two deaths. One is the 16-year-old girl who wanted to lose some weight and went on a popular low carb, high fat, high protein diet, collapsed in school and died suddenly. Autopsy showed a massive abnormality in the heart.

"Another case, a 41-year-old man, no prior history of heart disease, collapsed suddenly and the same thing, the autopsy showed a massive heart malfunction. A third case, a man happened to have a heart scan prior to going on the diet and he got a clean bill of health, but after about two years on this popular low-carb diet, developed chest pain, had stress test changes and angiogram that showed a massive blockage in the heart."

People claiming to have been harmed by high-protein diets reported health problems on a PCRM's Web site registry. The online registry found:

  • 42 percent reported loss of energy
  • 31 percent reported difficulty concentrating
  • 22 percent reported kidney problems
  • 20 percent reported heart-related problems

    Barnard notes, "The question is this: are these coincidences or could this be a contributor? We are asking the U.S. Centers For Disease Control to investigate what problems, what fatalities, could be or could not be linked to this kind of diet fad. "

    Although the evidence, so far from the small number of documented cases and PCRM Web site survey, does not present hard scientific evidence or proof of harm from the Atkins diet, there is enough of a pattern to warrant real studies, Barnard says.

    Since its inception in 1970, the Atkins diet has been controversial. It's also been very popular, especially in recent years. Barnard's advice to people who are on those type of diets is to get off of them and follow the dietary guidelines that health authorities have established.

    He says, "The fad approach has said, 'Let's forget the fact that fat and cholesterol are linked to heart disease and let's forget the fact that a meaty diet is linked to colon cancer.' We've known that for a long period of time. In the pursuit of short-term weight loss, people have gone on this approach. If we look, however, who on this planet are the skinniest and the thinnest and the best with a long-term weight management, it's not people on high protein diets. It's people in Asia who are on diets based on plant foods, rice noodles and vegetables or if you look at vegetarians, they are thinner and live longer than anyone else, so we should be going on that pattern."

    The online survey is not a scientific study, so there are no hard facts to say definitively that the Atkins diet is harmful. But the PCRM says there is enough evidence for concern.

    A major effort by the CDC is needed to keep track of the health effects beyond the limited clinical trials, according to Barnard. Those trials have focused on weight loss and only peripherally addressed the underlying health issues.

    The PCRM notes the following in its report:

    • While a few recent studies have noted that high-protein, carbohydrate-restricted diets facilitate modest short-term weight loss, no studies have investigated the long-term health consequences of consuming such diets for weight-loss purposes.
    • Diets high in fat, especially saturated fat, are associated with increased risk of cancer, diabetes and heart disease, and diets high in animal protein have been shown to increase the risk of kidney problems, osteoporosis, and some types of cancer.

    Because fiber is found only in plant foods, and high-protein, high-fat, carbohydrate-restricted diets tend to be low in plant foods, these diets are also typically low in fiber. Low fiber intake is associated with increased risk of colon cancer and other malignancies, heart disease, diabetes and constipation.

    Some high-protein, very-low-carbohydrate, weight-loss diets are designed to induce ketosis, a state that also occurs in uncontrolled diabetes mellitus and starvation.

    When carbohydrate intake or utilization is insufficient to provide glucose to the cells that rely on it as an energy source, ketone bodies are formed from fatty acids. An increase in circulating ketones can disturb the body's acid-base balance, causing metabolic acidosis. Even mild acidosis can have potentially deleterious consequences over the long run.

    For these reasons, high-protein, high-fat, low-fiber and carbohydrate-restricted diets, such as the Atkins Diet, especially when used for prolonged periods, are expected to increase the risk of multiple chronic diseases and other health problems, despite the weight loss that may accompany their use, Barnard says.

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