Atkins Nutrition Diet Plan-Free

Effects of a 6 Month Adherence to a Very Low Carbohydrate Diet Program

A team of researchers at Duke University Medical Center has conducted an ongoing weight-loss study that entailed monitoring 50 subjects who were following the Atkins Nutritional ApproachTM. The individuals were monitored throughout the initial six-month period, with data that included results of laboratory tests, weight/waist measurements, diet composition, symptoms and side effects. The results, published in the peer-review American Journal of Medicine, suggest that the ANA is not only effective in weight loss and management, but manifests significant improvement in a number of cardiovascular disease risk factors.

Key points:

The overweight or obese healthy volunteers who wanted to lose weight were placed on a very low-carbohydrate diet (less than 25g/day of carbohydrates), including nutritional supplementation, recommendations about exercise, and attendance at group meetings to determine the effect of a very low-carbohydrate diet program with no limit on caloric intake.

Forty-one individuals or 80 percent followed the nutrition regimen for the duration of the study.

The regimen led to sustained weight loss during the six-month period. Body weight decreased significantly by 10.3 percent (or an average of almost 20 pounds) from the beginning to the end of the study. Body mass index decreased by 3.2 kg/m2. Average percentage of body fat significantly decreased by 2.9 percent.

Total cholesterol level decreased by 11mg/dL; low-density lipoprotein cholesterol level decreased significantly by 10 mg/dL; triglyceride level decreased with a high level of significance by 56 mg/dL; high-density lipoprotein (HDL) cholesterol level increased significantly by 10 mg/dL; and the cholesterol/HDL cholesterol ratio was also significantly decreased by 0.9 units.

There were no serious adverse effects. Further controlled research is warranted.

In addition to the ongoing weight-loss study, Duke researchers also performed a two-armed, randomized controlled trial to study 120 obese hyperlipidemic adults. The study compared the controlled carbohydrate Atkins Nutritional ApproachTM to the American Heart Association (AHA) Step I diet advocated by many health professionals for cardiovascular health. In each arm of the study, 60 subjects were monitored for clinical values, side effects, body composition and bone-mineral density. Food records provided measures of caloric intake as well as carbohydrate, protein and fat intake. This comparative study demonstrated that subjects on a controlled carbohydrate eating program lost both more weight and more body fat than subjects following a low-fat diet. In addition, those subjects controlling their carbohydrate intake showed a decrease in triglycerides and total cholesterol as well as an increase in HDL (good)cholesterol levels. The full results of this research, including some groundbreaking data regarding our expanding knowledge on the role of cholesterol in heart disease, has been submitted for publication in scientific journals.

Atkins works better for guys

Low-carb eating plans like the Atkins Diet are more effective for men than women, a new study reveals.

A third of 15 men who consumed fewer carbohydrates over a period of 50 days lost more than 10 pounds with one participant dropping 25 pounds, researchers at the University of Connecticut said.

But the weight loss among the 13 women who followed the same diet was not as dramatic, they reported in the journal Nutrition and Metabolism.

The study, which was partly funded by the Atkins company, also revealed that a low-carbohydrate diet was up to three times more effective at trimming fat from dieters mid-sections than a low-fat one. Bill Hoffmann

Flab To Fab: I Lost 82 lbs. With Atkins!
A great AFTER shot is the icing on the low-carb cake for a great Atkins success story. Feast your eyes on gorgeous Zoanne S. Before linking up with the awesome Atkins Nutritional Approach, she was a whopping 82 pounds heavier.

Atkins Research Update, July 2003

As an ongoing service from Atkins Health and Medical Information Services to practicing physicians and medical and lifestyle journalists, our communications department provides the latest developments in clinical research on controlled carbohydrate nutritional practices and the Atkins Nutritional ApproachTM (ANA) as they occur and are reported. If you would like any further information or access to our complete library of published controlled carbohydrate research, please contact Melissa Skabich or Gina Mangiaracina at 212-714-0300 or mskabich@wwafsp.com.

With this issue, we begin a new feature: Patient Case Reports. Researchers have begun to send us relevant individual case histories from their daily clinical practices and others that merit particular notice from ongoing studies. Oftentimes, study results and reports understandably overlook the specific lessons to be learned from individual patients.

This first in what will become a series of case reports is from Joseph Hickey, M.D., a practicing physician from North Carolina who is also currently engaged in research on metabolic syndrome and lipids.

CASE REPORT: WHEN CHOLESTEROL NUMBERS LIE

Triglycerides have long been an enigma to organized medicine. Not only have we misinterpreted where they come from, we have misinterpreted the importance of measuring them. In fact, contradictory conclusions about cholesterol have made the issue exasperating and confusing for much of the general population. But medical professionals now have greater resources for the understanding of lipid profiles and their effect on a patients well being. The following case study is one example of how a patient, who on initial examination appeared quite healthy, was actually at risk for serious health problems.

P.C. first came to see me for a complete physical examination in September of 1997. His age was 56 years. He exercised regularly by jogging six to 10 miles per week. His body weight was 205 lbs., height 61, body mass index 27.5 and waist size 37 inches at the umbilicus. He followed a low-fat diet consistent with the Step 1 American Heart Association Diet. He was essentially asymptomatic.

His lipid profile was performed and showed a total cholesterol of 186 mg. His HDL (high-density, or good) cholesterol was 44 mg, triglycerides 189 and LDL (low-density, or bad) cholesterol calculated at 104 mg. However, he also had elevated liver chemistries, consistent with fatty liver, a sign of insulin resistance.

Still, with his LDL cholesterol at 104 mg and his negative previous history of heart disease or diabetes, we undertook primary prevention by following the low-fat diet recommendations of the American Heart Association. In 1997, I was perfectly justified in calling a triglyceride level of 189 normal according to the National Cholesterol Education Program. However, now I feel anything above 100 is abnormal.

Triglycerides are how non-fat foods and/or carbohydrates are converted into cholesterol. As a result, eating a pure protein and fat diet, such as the one prescribed for the Induction phase of Atkins, would lower the amount of triglyceride production because the diet lacks enough carbohydrates to produce high quantities of glucose.1,2,3 You must have glucose to produce triglycerides because glucose is converted into glycerol molecules, which create a foundation for the three fatty acids constituting triglycerides.

I saw P.C. again in April of 2001 and at that time, his body weight was 219 lbs., with a body mass index of 28. His blood pressure was 132/102 and his lipid panel showed significant deterioration. This was despite his continued low-fat dieting and regular exercise. His total cholesterol went up to 220 mg. His LDL cholesterol went up to 129 mg and his triglycerides went up to 316. P.C. was perplexed at the rise in his triglyceride level, which rose from 189 to 316. Fortunately, I had found the answer.

After using Atkins for the last two years on my patients, I found that triglycerides come exclusively from carbohydrates being converted into cholesterol. This was indicative of a defect known as the Metabolic Syndrome, meaning that P.C. had glucose intolerance and insulin resistance.3,4,5

The typical examples of glucose intolerance/insulin resistance show a predominance of small, dense LDL and too few large HDL combined with too many LDL particles per liter of blood. That gave P.C. more than six times the average risk of a heart attack, according to the Quebec Cardiovascular Study of 1996. 6

Triglycerides are the key ingredient in coronary artery disease. This has been demonstrated in at least 30 studies since 1996, showing that the diameter, or size, of the LDL particle and the number of particles per liter of blood, are much more accurate in predicting heart disease than the total bad cholesterol.6,7,8,9,10

P.C. had LDL cholesterol of 129 mg, but 81 mg of this was carried by small, dense particles. If you have greater than 30 mg of your bad cholesterol carried by small, dense particles, you have nine times the risk of coronary artery disease progression or growth of cholesterol in the wall of your artery. 11 His HDL cholesterol was 41 mg, but likewise only 13 mg of this was large HDL cholesterol. If one were to look at your HDL cholesterol and break down how much large versus small HDL you have, you could tell whether or not the good cholesterol is going to be protective or non-protective. Several angiographic studies bear this out.

THE FIX

Over the previous two years, I had studied Atkins and saw how much it improved small LDL and increased large HDL. I gave P.C. one of two choices: either start some medication to lower his risk immediately, or change his lifestyle and go on a low carbohydrate diet consistent with Dr. Atkins philosophy. P.C. chose carbohydrate control.

Over the next three months, his body mass index came down from 28 to 26. His weight came down from 219 pounds to 201 pounds. His exercise tolerance and jogging time increased. His blood pressure resolved at 120/80. Most importantly, his LDL particle size and number improved. He now had 0 mg of small LDL, 0 mg of medium LDL and all large, fluffy LDL cholesterol. His total cholesterol, interestingly enough, went up to 223 mg, and his LDL cholesterol went from 129 mg to 144 mg, but his good HDL cholesterol went from 41 mg to 60 mg, which is a tremendous improvement. His triglycerides fell from 316 mg to 75 mg without medication. This was all accomplished with three months on Atkins.

P.C. is one of 500 examples I have in my own patient population. P.C.s exercise tolerance, blood pressure and lipids are now perfect. In the interest of his overall good health, P.C. will never be on a low-fat diet again.

Dr. Joseph Hickey, Hilton Head Island, SC

Westman EC,Yancy WS et al. Effect of six-month adherence to a very low carbohydrate diet program. Am J of Med 2002; 113 30-36

Hickey J, Hickey L, Heritage Medical Center Partners, Hilton Head, SC, Hepburn, J., Yancy W, Westman, EC, Duke University, Durham, NC. Treating the metabolic syndrome with carbohydrate restriction. Abstract presented at Nutrition Week 2003, Amer Soc of Parenteral and Enteral Nutrition.

McLaugghlin T. et al. Carbohydrates Induce Hypertriglyceridemia. The link between plasma insulin and triglycerides. J. Clin Endocrinology Metab 2000; 85; 3085-3088.

Reaven GM et al. Insulin resistance and hyperinsulinemia in individuals with small dense LDL particles. J Clin Invest 1993; 92: 141-146.

Grundy SM. Hypertriglyceridemia, atherogenic dyslipidemia and the metabolic syndrome. Am J Cardio 1998; 81(4a) 18B 25B.

LaMarche B et al. Small, dense low-density lipoprotein particles as a predictor of risk of ischemic heart disease in men. Quebec Cardiovascular Study, Circulation 1997; 95: 69-75.

Freedman DS, Otvos J, et al. Relation of lipoprotein subclasses as measured by proton nuclear magnetic resonance spectroscopy to coronary artery disease. Arterioscler Thromb Vasc Biol 1998;18;1046-1053.

Otvos, J. Measurement of triglyceride rich lipoproteins by nuclear magnetic resonance spectroscopy. Clin Cardiol 1999; 22: (6 supplements) II 21-27.

Kuller LH et al. NMR Resonance spectroscopy of lipoproteins and the risk of coronary heart disease in the cardiovascular health study.

Austin MA et al. Low density subclass patterns and the risk of myocardial infarction. JAMA 1988; 260: 1917 1921.

Rosenson, RS, Otvos J et al. Relations of lipoprotein subclass levels and low-density lipoprotein size to progression of coronary artery disease in the (Plac 1) trial. Amer J Card 2002; 90: 89-94.

SUNY STUDY TO EXPLORE METABOLIC ADVANTAGE OF ATKINS; ITS NOT JUST CALORIES

Richard Feinman, M.D., and Eugene Fine, M.D., of Downstate Medical Center (State University of New York) in Brooklyn, New York, have launched a study funded by the university to explore the importance of the metabolic advantage: the apparent greater weight loss on low carbohydrate diets, compared to other diets of similar caloric value. They suspect, based on work of Donald Layman, M.D., of the University of Illinois, and others, that thermogenesis (heat produced from the burning of calories) due to protein turnover is the likely cause of this phenomenon. By looking at the inefficiency of the process involved with protein turnover for gluconeogenesis (the process by which the liver contributes to maintenance of normal blood sugar levels through synthesis of glucose), these investigators stand to help explain why in the end, not all calories are all created equally. In the first phase of their study, the researchers are currently making measurements on diets of different macronutrient composition.

OREGON RESEARCH SHOWS ATKINS APPROACH AS EFFECTIVE AS LOW-FAT DIETS

In the wake of newly published studies in The New England Journal Of Medicine comparing the Atkins Nutritional ApproachTM to low-fat diets, recent research from the University of Oregon offers further confirmation of the possible superiority of controlling carbohydrates over lowering fat intake in dieting. This new research examined the impact of following the ANATM versus a calorie-matched low-fat diet. The researchers concentrated on changes in weight and body composition that may occur while on each program. Of the 25 otherwise healthy, obese men and women, 13 subjects were randomly assigned to the Atkins group, which consumed a typical Induction level of carbohydrate (20 grams/day), and 12 subjects participated in the low-fat group (fat equaled less than 30pct. of their intake). The caloric intake of both the Atkins and low-fat groups were the same. At the end of the 42-day study, the Atkins group lost an average of 14.3 pounds and the low-fat group lost an average of 11.4 pounds. While researchers concluded this was not a significant difference in weight loss and found no other significant differences in the composition of weight loss or changes in anthropometric (human body measurements) indices between groups, the Atkins group lost slightly more weight.

Reference: D Stadler1, V Burden1, M McMurry1, G. Gerhard1, W Connor1, N Karanja2. School of Medicine, Oregon Health and Science University1 and Kaiser Permanente Northwest Center for Health Research2, Portland, OR 97229.

LOW-IRON, CARBOHYDRATE-RESTRICTED DIET FOUND MORE EFFECTIVE THAN PROTEIN-RESTRICTION FOR END-STAGE KIDNEY DISEASE PATIENTS

Is a controlled carbohydrate nutritional regimen like Atkins a better option for patients with kidney disease than the usual recommendations According to recent research published in Diabetes, evidence suggests that dietary factors other than protein consumption play an important role in the progression of kidney complications (diabetic nephropathy) during end-stage renal disease. The purpose of this study was to determine whether a carbohydrate-restricted, low-iron, antioxidant-enriched diet or, CR-LIPE, may delay and improve the outcome of diabetic nephropathy to a greater extent than the commonly recommended protein-restricted diet. It was found that CR-LIPE was 40-50 percent more effective than standard protein restriction in improving renal function and overall survival rates.

One-hundred ninety-one Type 2 diabetics were randomized to follow either CR-LIPE or the standard protein-restriction diet. The researchers monitored for the following: the doubling of serum creatinine (component of blood that increases in advanced stages of renal disease), the development of end-stage renal disease and death rates.

After four years, serum creatinine concentration doubled in 19 patients on CR-LIPE (21 percent) and in 31 patients following the protein-restricted diet (39 percent). Renal replacement therapy or death occurred in 18 patients on CR-LIPE (20 percent) and in 31 subjects following the protein-restricted diet (39 percent).

Reference: Facchini, F.S., Saylor, K.L., A low-iron-available, polyphenol-enriched, carbohydrate-restricted diet to slow progression of diabetic nephropathy, Diabetes, 52(5), 2003, page 1204-1209.

EXPOSING THE BONE DETRIMENT MYTH: RECENT RESEARCH SHOWS THE BENEFITS OF CONTROLLED CARBOHYDRATE NUTRITION FOR BONE HEALTH

Two recent studies, both published in the Journal of Nutrition, examined the effect of protein intake on bone health. In the first study, conducted by Grand Forks Human Nutrition Research Center, U.S. Department of Agriculture, a series of short-term nutrition intervention trials were performed. Healthy adults consumed either a low, medium or high level of dietary protein. The researchers found the low-protein diet induced changes in hormonal signals of bone metabolism, which may negatively impact bone health. These hormonal changes (increase in parathyroid hormone) did not occur on either the moderate or high-protein diet.

These findings were consistent with recent population studies demonstrating that individuals who consumed low-protein diets had reduced bone density. The researchers also noted that there were no definitive nutrition intervention studies that show a detrimental effect of a high-protein diet on the skeleton.

In the second study, conducted by the University of Connecticut, 15 healthy postmenopausal women consumed diets with similar calcium content (approximately 600 mg), but the diets were either low or high in meat (12 percent vs. 20 percent of energy as protein), for eight weeks. Although there was an initial spike in urinary calcium excretion, which is typically seen when protein intake increases, the levels quickly returned to normal. Urine and blood tests showed there was no difference in calcium retention during the high or low-meat period over time, and the diets did not affect urinary calcium loss or indicators of bone metabolism. The researchers concluded that a high-meat diet, when compared with a low-meat diet for eight weeks, did not affect calcium retention or biomarkers of bone metabolism in healthy postmenopausal women.

Reference: Roughead, Z. K., Johnson, L. K., Lykken, G. I., et al., Controlled high meat diets do not affect calcium retention or indices of bone status in healthy postmenopausal women, The Journal of Nutrition, 133(4), 2003, pages 1020-1026.

Reference: Kerstetter, J.E., OBrien, K.O., Insogna, K.L., Low protein intake: the impact on calcium and bone homeostasis in humans, The Journal of Nutrition, 133(3), 2003, pages 855S-861S.

INCREASE IN BLOOD SUGAR IS A RISK FACTOR FOR HEART ATTACK IN MEN TAKING HIGH BLOOD PRESSURE MEDICATIONS

The March 2003 issue of the British Medical Journal features a study linking high blood pressure treatment with impaired insulin and glucose metabolism and heart attacks. The researchers concluded that an increase in blood sugar (which often results from excessive carbohydrate consumption) was a risk factor for a heart attack in men taking high blood pressure medications, indicating that both an insulin resistant state combined with blood pressure medications, specifically beta blockers and diuretics, increase the risk of a heart attack.

It is already known that individuals with hypertension are more resistant to insulin and glucose uptake. The question of concern for many health professionals was whether changes in glucose metabolism evidenced in high blood pressure patients increases the risk of a heart attack. Most recently, researchers in Sweden investigated blood glucose levels on the risk of developing a heart attack, with particular emphasis on people taking blood pressure medications.

This study was based on the 1,860 50-year-old men who participated in a health survey in 1970-73. These men were re-examined 10 years later, at age 60, and then followed for more than 17 years as part of the Uppsala study. The results showed that participants being treated for hypertension at age 60, with an average blood pressure of 154/94, had greater indicators for the metabolic syndrome. Twenty-three percent of participants treated for high blood pressure suffered a heart attack, as compared to 13.5 percent in the non-treatment group, a statistically significant difference. Participants who suffered a heart attack after the age of 60 had a greater increase in blood glucose between age 50 and 60 than those who did not have a heart attack.

Reference: Dunder, K, Lind, L, Zethelius, B, Berglund L, et al. Increase in blood glucose concentration ruring antihypertensive treatment as a predictor of myocardial infarction: population based cohort study, British Medical Journal, 326(7391), 2003, page 681.

Reference: Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, PO Box 609, SE-751 25 Uppsala, Sweden. kristina.dunder@pubcare.uu.se.

HARVARD RESEARCH SHOWS HIGH-PROTEIN DIET HAS NO ASSOCIATION WITH BREAST CANCER

ontrary to a popular misconception, a recently published study from Brigham and Womens Hospital in Boston, Massachusetts, provides compelling evidence that diets high in animal protein are not associated with increased breast cancer risk. This finding stems from the landmark Nurses Health Study. Researchers followed 88,647 women for 18 years, with five assessments of diet by food frequency questionnaire. Among study participants, 4,107 developed invasive breast cancer. The researchers found no evidence that intake of meat or fish during mid-life and later was associated with risk of breast cancer. Results did not differ by menopausal status or family history of breast cancer.

Reference: Holmes, M.D., Colditz, G.A., Hunter, D.J., et al., Meat, fish and egg intake and risk of breast cancer, International Journal of Cancer, 104(2), 2003, pages 221-227.

NEW YORK UNIVERSITY STUDY SHOWS POOR BLOOD SUGAR LEVELS CAN AFFECT MEMORY IN ELDERLY

Approximately 25 percent of individuals aged 65 and above have memory problems. A recent study out of New York Universitys Center of Brain Health established an association between blood sugar regulation and the brain, demonstrating the health benefits of controlling blood sugar levels. Thirty non-diabetic men and women between the ages of 53-89 were evaluated in an outpatient research setting. Among those studied, decreased blood sugar regulation (unstable blood sugar) was associated with decreased general mental performance, memory impairments and deterioration of the hippocampus, the brain structure involved in learning and memory. This observation on aging brain injury may have substantial medical impact, considering the large number of elderly individuals with impaired glucose metabolism. The researchers concluded that, better lifetime management of blood sugar may improve memory in old age and perhaps even reduce the risk of hippocampal damage and possibly Alzheimers disease.

This research suggests that the blood sugar stability offered by a controlled carbohydrate nutritional approach may be a useful tool in improving and preventing memory loss in the elderly, while a low-fat approach, commonly prescribed among the elderly may actually exacerbate the problem.

Is it just possible that Dr. Robert C. Atkins was right That his high-fat, low-carb plan, ridiculed for 30 years as dangerous nonsense, actually is a good, safe way to lose weight

The dietary elite are not ready to change their collective mind, but a half-dozen or so new studies have taken an objective look at the presumed evils of Atkins, and the results have been little short of astonishing:

During a few months on the Atkins diet, people lose about twice as much as on the standard low-fat, high-carbohydrate approach recommended by most health organizations.

They do so without seeming to drive up their risk of heart disease. Rather than going kaflooey, their cholesterol, triglycerides, blood pressure and ominous bloodstream inflammation generally improve, perhaps even more than on the standard diet.

They appear to lose more weight even while actually consuming more calories than people on a so-called healthy diet.

All of the experiments were short and small. None by itself would make a big stir. But taken together, they undermine much of what mainstream medicine has long assumed about the Atkins diet.

Some scientists are dismayed by the data and a little incredulous about it, says Gary Foster, who runs the weight-loss program at the University of Pennsylvania. But the consistency of the results across studies is compelling in a way that makes us think we should investigate this further.

Until now, the opinion of the medical world on this subject has been essentially unanimous: Any diet that emphasizes meat, eggs and cheese and discourages bread, rice and fruit is nutritional folly.

The American Medical Association set that tone a year after the book, Dr. Atkins Diet Revolution, came out in 1972. Its sarcastically worded critique dismissed the diet as potentially dangerous. It called its scientific underpinning naive and biochemically incorrect. And it scolded book publishers for promoting bizarre concepts of nutrition and dieting.

On the Atkins diet, up to two-thirds of calories may come from fatmore than double the usual recommendationand that violates everything medical professionals believe about healthy eating. Carbohydrates are the foundation of a good diet, most say. Eating calorie-dense fat is what makes people fat, and eating saturated fat is what kills them.

Despite this, Atkins books have sold 15 million copies, uncounted millions have tried the diet, and practically everybody has heard of someone who dropped a ton of weight on the Atkins plan.

Finally, several research teams around the country have put Atkins to the test, driven largely by weariness at having nothing solid to tell patients and, in some cases, a desire to prove Atkins wrong. One study was even sponsored by the American Heart Association, long an Atkins skeptic.

None has been published yet, but summaries have been given at medical conferences. They all show pretty convincingly that people will lose more weight on an Atkins diet, and their cardiovascular risk factors, if anything, get better, says Dr. Kevin OBrien, a University of Washington cardiologist involved with one of the studies.

This is not the end of the story. The studies say nothing about how much people lose when they stay on Atkins more than a few months, whether they keep the weight off for good and whether their cholesterol rebounds when they stop losing weight.

Nevertheless, three decades of dietary gospel are in doubt, and those questioning it include some of the most prominent names in obesity research. For instance, one of the new studies was conducted by Foster with Drs. Samuel Klein and James Hill, the current and past presidents of the North American Association for the Study of Obesity, the premier professional group.

Im part of the obesity establishment, says Foster, who has published more than 50 scientific papers on the subject. Ive spent my life researching ways to treat obesity, and 100 percent of them have been low-fat and high-carb. Now Im beginning to think, it isnt as it has appeared.

His Atkins study was intended to show it doesnt work, yet after three months, the overweight men and women had lost an average of 19 pounds, 10 more than people on the standard high-carb approach.

The big surprise was cholesterol. The Atkins dieters overall profile changed for the better. Although their bad cholesterol went up seven points, their good cholesterol rose almost 12. (Changes in the high-carb dieters were less dramatic. Their bad cholesterol went down slightly while their good cholesterol remained unchanged.)

The largest difference was in triglycerides. The Atkins dieters dropped 22 points. The low-carb dieters didnt budge.

It was unexpected, to put it mildly, Foster said. It made us think maybe there is something to this.

Despite these data, the Atkins diet still gives many health professionals the willies. It encourages people to eat bacon, butter, prime rib and lots of other things loaded with saturated fat. And it lectures against such mainstay carbohydrates as grains, pasta and starchy vegetables, especially in the diets first cold-turkey stage; plenty of other healthy things, including many low-carb green vegetables and olive oil are allowed.

There are many principles in the Atkins diet that go against what we know, says Dr. Robert Eckel of the University of Colorado, senior author of the heart associations policy on high-protein diets. It keeps people away from staples of the diet that we know are associated with less heart disease.

Volumes of research suggest that people have the best chance of avoiding heart disease, high blood pressure and cancer if they eat a varied diet with plenty of fruits, vegetables and grains.

Its scary if people leave out these very important food groups and just depend on high-fat, high-protein foods, says Wahida Karmally, nutrition director at Columbia Universitys clinical research center.

Furthermore, people on the Atkins plan may get a quarter of their daily calories from saturated fat, more than double the heart associations recommendation. Animal experiments and studies of large groups of people long ago convinced many experts that too much saturated fat clogs the arteries and leads to heart attacks.

Mainstream scientists wave off the Atkins camps answer to thisthat saturated fat is bad only if eaten with large amounts of carbohydrates. Otherwise, its harmlessly burned off.

When carbs are the primary fuel source, there are certain risks in excessive fat consumption, says Colette Heimowitz, the Atkins organizations research director. But in a controlled-carb setting, when fat is the primary fuel source, the rules change. Those risk factors do not show up.

So how do the traditionalists explain the cholesterol improvement seen in the Atkins dieters Weight loss. Slimming down reliably improves cholesterol levels, and they say its benefits probably overshadowed any damage done by all the unhealthy fat that people ate.

Why people lose more weight on the diet is also not clear, although some researchers say they buy one of Atkins arguments: People stick with it because they are not constantly hungry. Fat and protein satisfy the appetite, the theory goes. But eating lots of carbohydrates raises insulin levels, lowers blood sugar, and eventually makes people ravenous.

But another of Atkins ideas on the subject is far more contentious. He argues that people lose more weight on his plan even if they actually eat more calories. Thats a violation of the laws of thermodynamics, skeptics say.

A calorie is a calorie as far as weight reduction is concerned, says Dr. Michael Davidson, director of preventive cardiology at the Rush Heart Institute in Chicago.

Or is it Some of the new studies suggest otherwise.

Dr. Stephen Sondike of Mount Sinai Medical Center in New York City put overweight teenagers on comparison diets for two months. The ones on Atkins lost twice as much as those on the low-fat diet. Yet they appeared to eat about 700 more calories a day than the others.

Less dramatic but still startling results came from another study at the University of Cincinnati. Women on Atkins lost twice as much while eating the same number of calories as the low-fat dieters.

Surprised Definitely, says Bonnie Brehm, a registered dietitian. We really dont know what the answer is.

And the Atkins weight loss was not simply dehydration, as Atkins critics often contend, since the Cincinnati dieters also lost twice as much body fat.

But even if the diet is reasonable for a few months of slimming down, what happens when people level off during the maintenance phase of the program Does their cholesterol soar if they eat all that fat without losing weight

He put fit men on an Atkins regimen for six weeks with orders not to lose weight, and nothing bad seemed to happen. Their good and bad cholesterol went up proportionately, and their triglycerides fell. Id like to see more data, Volek said, but ours provides evidence it doesnt have a negative effect on your heart.

This federally sponsored project will randomly put 360 overweight men and women on the Atkins plan or the U.S. Department of Agricultures standard high-carb, low-fat diet, then watch them in painstaking detail for at least two years.

The study will try to answer three questions about Atkins, says Hill, who directs the University of Colorados Center for Human Nutrition. Does it produce weight loss Is it a safe weight loss And is it any better in the long run than anything else that has come along

Scientists will analyze the volunteers blood and cholesterol in every way they can think of, as well as check their bone density, kidney function, body composition, exercise tolerance and more.

Despite the professions unease at the findings so far, some of the researchers involved expect that if the Atkins approach proves safe and effective in larger, longer studies, those opinions will eventually change.