08/06/2002 - Updated 10:34 PM ET

Researchers chew the fat on merits of the Atkins diet

By Nanci Hellmich, USA TODAY

The Atkins low-carb, high-fat diet is supposed to be simple, but it's raising complex medical and nutrition questions. Now two new studies show that those who follow the diet can lose significant amounts of weight, but other research is raising concerns about the safety of the program, linking it to an increased risk of kidney stones and bone loss.

Fueled by recent media attention and reports of successful weight loss, Dr. Atkins' New Diet Revolution by cardiologist Robert Atkins, is No. 1 on USA TODAY's Best-Selling Books List. First published in 1972, the diet allows dieters to consume steak, hamburger, pork, butter, cheese and other high-fat foods and has them cut way back on carbohydrates including pasta, sweets, some starchy vegetables and many fruits.

Some of the nation's leading obesity researchers and nutritionists are outraged by the diet, arguing that it runs contrary to the advice of most major health organizations, which advocate a diet relatively low in saturated (animal) fat and high in complex carbohydrates (grains, vegetables). Those recommendations are based on scientific evidence that a diet rich in fruits and veggies and low in saturated fat reduces the risk of heart disease, some types of cancer and other health problems.

Still, many dieters swear by the Atkins diet. And until recently, there haven't been many studies investigating its safety and effectiveness.

In one new study, conducted at Duke University Medical Center and funded by a grant from the Robert C. Atkins Foundation, participants ate a very low carbohydrate diet of 25 grams a day for six months. They could eat an unlimited amount of meat and eggs, two cups of salad and one cup of low-carbohydrate vegetables such as broccoli and cauliflower a day. Of the 50 patients enrolled, 80% adhered to the diet for the entire study, losing an average of 10% of their original body weight. The average weight lost was approximately 20 pounds, says Eric Westman, associate professor of medicine at Duke University Medical Center.

The Atkins dieters also had improvements in blood cholesterol and triglycerides, but researchers don't know if those changes are due to losing weight, cutting back on junk food or the makeup of the diet.

In another pilot study, obesity researchers at three universities recruited 63 people who were 30 or more pounds overweight and assigned them to one of two programs. One group was given a copy of Dr. Atkins' New Diet Revolution. The other group was put on a conventional diet with about 30% of calories from fat, 55% from carbohydrates and 15% from protein.

At the end of six months, those following the Atkins diet lost about 10% of their starting weight and those on the conventional diet lost about 5%. Atkins dieters also were more likely to stick with the plan than conventional dieters.

The Atkins program "may give people a way to eat fewer calories," says lead researcher Gary Foster, clinical director of the Weight and Eating Disorders Program at the University of Pennsylvania School of Medicine. He says researchers don't know if the benefits of losing weight outweigh the drawbacks of eating a diet high in saturated fat.

There is nothing miraculous about the Atkins diet, but if you put people on a low-calorie diet, they lose weight, says Keith Ayoob, a spokesman for the American Dietetic Association. "It's the number of calories, not where they come from."

Foster and fellow researchers are going to continue to investigate the Atkins diet with a longer-term study sponsored by the National Institutes of Health. They will look at several different aspects, including whether the diet may be more useful for some people than others and how much people are able to exercise while eating a low-carb diet. They also want to investigate why some dieters seem more likely to stick with the Atkins program than a more conventional diet.

One theory suggests that people on the Atkins diet may eat less because of a loss of appetite due to ketosis, a state in which the body partially breaks down body fat, producing organic compounds called ketones as fuel. This is due to the limited carbohydrates.

Colette Heimowitz, an Atkins spokeswoman, says the latest version of the diet book puts less emphasis on ketosis because people may not have to be in this state to lose weight on the program. She says people don't get as hungry because the fat in the plan has a positive impact on blood sugar and insulin, and protein makes people feel full longer. But other experts say these theories are unproven and need further investigation because hunger is complex.

Westman of Duke says people may get positive reinforcement from losing weight fast on Atkins, which keeps them going. Or this diet really may appeal to people who prefer to eat this way. "There are some meat lovers, and on this kind of diet you can eat a lot of meat," he says. "Still, we need more research to determine the safety of the diet."

Some researchers have concerns about several medical issues. According to a study by researchers at the University of Texas Southwestern Medical Center in Dallas, the Atkins diet may increase the risk of kidney stones and bone loss. For this study, 10 healthy subjects ate a regular diet for two weeks, then for two weeks they followed a highly restrictive, Atkins-based diet that included some vegetables but no fruits and 20 grams or less of carbohydrates a day. The participants then ate a less restrictive form of the diet for the final four weeks.

Based on blood and urine tests, researcher Chia-Ying Wang concludes that "there was an increased risk of developing kidney stones and a possible increase in the risk of bone loss." The findings are reported in the August American Journal of Kidney Diseases. "We think the diet's combination of low carbohydrates and high animal protein results in sufficient acid to increase the risk for certain kinds of kidney stones," she says.

Heimowitz says studies of six months show there is an adaptation to the program without any kidney stone formation or bone loss. But she agrees with the researchers that those following the diet should take a multivitamin and drink adequate water.

The food composition of the Atkins plan continues to trouble many experts. "You don't eat just to get thin," says Barbara Rolls, a nutrition professor at Pennsylvania State University. "You eat a good balanced variety of foods and nutrients for a lot of other reasons, which have to do with cardiovascular health, cancer protection, bone health."

Rolls and Ayoob wonder whether most people who lose weight on the diet will keep the weight off long-term by eating this way. "Do people really want to give up bananas and their favorite fruits?" Ayoob asks.

Says Rolls, "You can achieve weight loss in lots of different ways. The real challenge is to figure out a way to keep it off."

http://www.usatoday.com/news/health...06-atkins_x.htm

Here's another "misconception". Why do they think we don't eat fruit? Not all fruits are created equal. I like bananas. But, according to the FDA Nutritional Database, one half of one medium-sized banana is one serving of fruit. Ever see anyone eat 1/2 a banana? I haven't.

I've added berries to my plan. I've even had cantalope and the other fruits listed in the plan. It's soooo frustrating when this supposed "experts" see only the parts of our woe that they want to.

Another good misconception is the kidney stone farce. Why do they develop? Lack of adequate water consumption. Since being on the Atkins diet, I drink 1.5-2 gal of water per day-no kidney problems. The tests don't indicate H2O intake. While I'm sure we might be more susceptible with this diet, probably due to the sodium levels, drinking more water will take care of it. A big fat DUH, to the researchers who just want to put in their two cents to the media and the public.

>A big fat DUH, to the researchers who just want to put in their >two cents to the media and the public.

But isn't that what you're doing? I just finished reading the water debate on another forum talking about how there is no evidence to support drinking so much water (as in no studies done)? Plus your non-stone symptoms hardly represent a sample from which to draw a conclusion. What is the basis for this kidney stone debate? Is this another case of a single piece of research that everyone cites or is there something more substantial behind this. I'm not up on the kidney stone / Atkins link.

The kidney stone farse was a "study" perfomed and then printed in some medical journal for doctors who work in the area of the kidneys and urinary tract. I apologize for not knowing the exact name of the journal.

The "study" took 10 healthy test subjects (no control group was used) and fed them their normal diet for 2 weeks, followed by a very "restictive-type Atkins Induction Phase" for 2 weeks, then a "maintenance phase for 4 weeks", then back to the way they always ate. The "study" lasted 10 weeks. The test subjects had their urine tested on a "regular" basis during this 10 week period and the "discovery" was that during the restricted carb portion of the test, the test subjects produced more of some enzyme that supposedly increases the risk for kidney stones in some people. The "study" also concluded that the test subjects were losing more calcium and therefore, more bone loss would occur with a low carb diet.

Please look around (anyone) and find the study and read it. I got this information straight from the woman who did the study. I emailed her and, I'm sorry, but I deleted that email.

Yes, we also need to see the amounts of water given-if that info exists in the study, and if they were supplemented according to Atkins guidelines.

It's still a very small group with what looks like a mediocre design, not to say or imply that the information is worthless. In fact, if it does not include increase in water intake and supplementation, it would impy the same thing Atkins does about the neccessity of inclusion of both with the diet.

Blue Too,

Did not the results of the Duke study include the risks of side effects with the diet and show there was a very small risk after 4 months? I'll check again, but I believe that it did. The Duke study had several hundred subjects vs. the 10 cited above.

If someone follows Atkins with use of green leafy vegetables and cheeses, it would seem very difficult to believe kidney stones would be a strong possibility. This would be far more likely with people consuming skim milk in high quantities, soda and little water(which is well established).

Interesting, but we need more info.

The big serious result of this "study" that was used to say there might be an increased risk (Jane note might) for kidney stones is that the urine pH decreased from 6.0 to 5.5. A medical tech wrote into another board and said that both numbers are within the normal range, and the normal number is closer to 5.5 than 6.0.

Hi all..I have been a lurker for a while and an Atkins fan for some time now. As far as the kidney stone issue and bone loss, the evidence is rather flimsy. From the study discussed:............"Based on blood and urine tests, researcher Chia-Ying Wang concludes that "there was an increased risk of developing kidney stones and a possible increase in the risk of bone loss." The findings are reported in the August American Journal of Kidney Diseases. "We think the diet's combination of low carbohydrates and high animal protein results in sufficient acid to increase the risk for certain kinds of kidney stones," she says.".................This opinion was based upon a study of 10 patients for two weeks on Atkins, hardly an indepth or adequate study to draw any conclusions. I am surprised the study was even published given this rather glaring weakness. Note that the researchers were unable to say that anyone actually developed a kidney stone, or osteoparosis, only that an extrapolation of their blook and urinary results MAY have created a predispositon. Much of the problem that we currently have in our explosion of obesity, diabetes, and heart disease is based upon extrapolation of what researchers think should happen rather than hard facts. We have strayed so far from evidence based medicine that I am embarrased. I am a physician, a board certified Ob-GYN., not something that I am especially proud of given the current sorry state of affairs. I do want you all to know that there are some medical people out there who are trying to take a hard look at actual evidence and fact. I do my best to educate my patients about the dangers of insulin resistance, and every day I see overweight women who "never eat any fat" and cannot understand why they have a BMI over 27. Good luck to all of you, and thank you all for all of the great research you post.

Hey, Doc, I hope you're pushin' Atkin's to all those ladies!!! Hang in there and welcome to the discussion!

Good to hear from somebody on the front lines.

Dear friends, Many of my patients have noticed my thinning waist size and have been eager to know how I have lost weight. Unlike a collegue of mine (a cardiologist who continues to follow the AHA dogma, but secretly uses Atkins when he needs to loose a few pounds) I have been totally honest about my weight loss. My weight problem began mainly after the birth of my last child when I gained nearly 50 pounds. My metabolism had always been high, but was slowing at age 43 and combined with the insulin resistance of the pregnancy hormones, and my high carb diet, I could neither stop eating or gaining. I believe this was because the state of pregancy increases steroid levels such as estrogen, progesterone and cortisol among others, which are tied to insulin resistance. Pregancy is also unique in that the placenta produces hormones, noteably HPL which makes glucose available to the fetus. This produces an even more pronounced effect on carbohydrate metabolism in which women are more prone to elevated glucose following carbohydrate feeds, but are also prone to more rapid drops in blood glucose due to the HPL effect. In short higher highs, lower lows and fatigued and hungry most of the time. I had always been intrigued by the unique carbohydrate metabolism of pregancy as an OB, but had never given it much serious thought until I was faced with my own situation which was getting out of hand. In addition to the weight gain during the pregancy, I also developed severe hypertension, which progressed to pre-eclampsia. Many of the articles I studied convinced me that Dr. Atkins (and others of the LCWOE) were correct. I agree with Dr. Atkins that most physicians do not understand the difference between diabetic ketoacidois and benign dietary ketosis. I DO NOT, however, recommend a diet which produces ketosis to women who are pregnant or lactating. We simply don't have enough information at this time, even though studies done retrospectively on women during the wartime siege in Holland (WWII) showed babies remained healthy although small, even though these women were probably in ketosis some of the time on their limited diets. I DO recommend Atkins to my non pregnant patients who are overweight and suffering from syndrome X diseases. My own BP has improved markedly since beginning Atkins, my energy is great, my HDL and triglycerides very good. All of the above is not intended as medical advice, simply my own testimonial.