The Great Diet Debate : page two :

The Eicosanoid story

Sears perceives the "almost invisible" eicosanoids as the keys to controlling disease. "Eicosanoids are the most powerful agents known to man." He sees the Zone diet as the way to control 'good' or 'bad' eicosanoids (without offering any proof). "Whether you want to move from illness to wellness or beyond wellness to optimal health, your only pathway is through the Zone. The balance of protein and carbohydrates controls the insulin-glucagon access, which in turn determines which eicosanoids your body makes are 'good' or 'bad.' Pretty simple actually". (not to say simplistic) Sears suggests that by using the Zone to control good and bad eicosanoids you can have a positive impact on almost every disease state, including heart disease, cancer, diabetes, depression, alcoholism, auto-immune diseases (including AIDS), reproductive disorders and many more. He stops short at promising eternal life but does promise "long life, increased vitality, and the greatest gift of all: good health. It's all possible in the Zone."

Alice Lichtenstein, a senior researcher at the Jean Meyer Human Nutrition Research Centre at Tufts University, summed up the Zone as "science fiction." She went on to express concern that people would take Sears' words seriously that the Zone diet can fight diseases like AIDS and cancer and that he might be taking advantage of "vulnerable people." One of many examples of this is in his section on the Zone and cancer. He provides his usual anecdotal evidence to support the role of the Zone as a cancer cure with the story of Judy Jones. "Her next MRI brain scan left the doctors shaking their heads in astonishment. The tumor was not only shrinking, it appeared to be dead - a highly unexpected if not unheard of result." Sears seems to discount the possibility that the radiation treatments and surgery could have had an impact on the tumor. His closing sentence is this, "Living in the Zone is the very best revenge against cancer."

In summary, the Zone is a reasonable low calorie weight loss diet that makes a series of preposterous and unsubstantiated claims.

I recently read that, " Unethical advertising uses falsehoods to deceive the public. Ethical advertising uses truths or bits of truth to deceive the public". Surely they can't have been writing about the diet doctors??

DR. ATKIN'S NEW DIET REVOLUTION

'Dr. Atkin's New Diet Revolution' delivers the low carbohydrate/high fat message that Dr. Atkins has been preaching for 30 years. His books have been vilified by the medical, nutritional and dietary establishment, but purchased by more than 10 million people and presumably read by many more than that. I'm reminded of movies that get panned by the critics, but have huge success at the box office. The 'Dr. Atkins New Diet Revolution' has no illustrations, a couple of bar graphs and figures and more than 500 pages, so people are not buying it for its graphics and presentation or its brevity.

My reading of Dr. Atkins is that he's not as bad as his reputation among dietary and medical professionals, and not as good as he likes to tell you in his book. His program is based on a shaky foundation, namely that the consumption of carbohydrates leads to insulin release, which in turn leads to fat storage, which ultimately leads to obesity. Atkins also believes that eating a high fat diet increases the body's tendency to burn fat as fuel. Like Gary Taubes and Barry Sears he points to the fact that despite North Americans being told for 25 years to cut back on fat, they have become fatter, ergo, carbohydrates are the problem.

This is sloppy reasoning, which would give you a failing grade in Logic 101 and can lead to some strange conclusions. It is referred to in Latin as 'post hoc, ergo propter hoc' (assuming something has caused an event merely because it preceded it).

Maybe our weight and health is just a language problem. The Japanese eat very little fat and suffer fewer heart attacks than the British or Americans. The French eat a lot of fat and also suffer fewer heart attacks than the British or Americans. The Chinese drink very little red wine and suffer fewer heart attacks than the British or Americans. The Italians drink excessive amounts of red wine and also suffer fewer heart attacks than the British or Americans. CONCLUSION: Eat and drink what you like.  Speaking English is apparently what kills you.

The above piece of humor is beginning to lose its point. With the spread of the North American fast food diet, obesity and heart disease are becoming global problems, affecting non-English speaking people of every race and colour.

I noted when writing about the Zone, carbohydrates don't make you fat, the leanest and longest living people in the industrialized world are the Japanese whose diet is dominated by complex carbohydrates and is low in fat. Atkins knows this, he knows the problem lies in simple carbohydrates and junk food, but this does not make controversial copy.

Atkins acknowledges a major debt to the work of British researchers Kekwick and Pawan who were conducting obesity related research in the 1950's and 60's. This is fairly obscure work which suggests that a high fat/low carb diet will promote more fat burning and weight loss than a calorically comparable diet high in carbohydrates. To Kekwick and Pawan, and by extension to Atkins, a calorie is not a calorie, because ingested fat calories lead to greater and faster losses of weight than do comparable carbohydrate calories.

I went into the archives to check the references for this work, which was published in the July 28,1956 issue of The Lancet. The first thing I noticed was that we were dealing with very low numbers of subjects monitored over a very brief time span.

Experiment 1

14 obese subjects were placed on 3 different 1000 calorie diets (high protein, high fat and high carbohydrate) for approximately one week. The high carbohydrate diet group gained 1.2 lbs. The high protein group lost 4.2 lbs. and the high fat group lost 6.3 lbs.

The authors wrote, "When calorie intake was held constant at 1000/day, the rate of weight loss varied greatly on diets of different composition. It was most rapid with high fat diets while weight could be maintained for short periods on diets of 1000 calorie value given mainly in the form of carbohydrates. As this rate of weight loss varied so markedly with the composition of the diets on a constant calorie intake, it is suggested that obese patients must alter their metabolism in response to the contents of their diet. The rate of insensible water loss has been shown to rise with high fat and high protein diets and to fall with high carbohydrate diets. This supports the suggestion that an alteration in metabolism takes place."

I was impressed with the care that the researchers took to control water intake (3000 ml) and the intake of sodium chloride, which totaled 10gms/day. This was not a classic experimental design with control and experimental groups, but rather was in the form of multiple case studies with the results of each subject averaged together. The researchers appeared to construct a rigorous protocol to control for any variables which might have affected the outcome of the results. But there were a few exceptions.

There is some vagueness about how many days each patient followed each dietary protocol. The bar graph which shows results states, "Mean of 5-9 days on each diet." Two of the results require comment. In a carefully monitored group of subjects in a residential hospital setting where they were required to do some exercise it seems surprising that people would gain weight on the 1000 calorie high carbohydrate diet. Another statement which jumped out at me, was when these two authors reported the results of this study at an obesity symposium, "A striking resistance to ketosis was seen in the obese. Even on a 1000 calorie, 90% fat diet, blood sugar was maintained within normal limits and ketosis was not observed in any of the subjects studied."

Both the above were possible and in her practice my wife has seen people on a 1000 calorie diet actually gain weight (usually associated with the menstrual cycle. She has also seen people on a very low carbohydrate diet of about 1000 calories who have not gone into ketosis. However, these are exceptions. I find it extra-ordinary that not one of the subjects was ketotic, when going into ketosis would be the norm. There was quite possibly some dietary contamination, in that one of the subjects subsequently reported that some food and alcohol were smuggled into the hospital by visiting friends. (This is hearsay and I debated whether to include the last sentence, so ignore it if you feel it's inappropriate, but it might help explain some surprising results).

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Experiment 2

Five obese subjects were placed on mixed diet of 2000 calories for 7 days. The same subjects were then placed on a high protein; high fat diet of 2600 calories for 7 days. Sure enough the mixed diet group gained 1.1 lbs. while 4 of the 5 high fat/high protein group lost an average of 2.8 lbs.

In his book, Atkins does not mention the small number of subjects nor the short duration of the studies. The most likely explanation for the rapid loss of the high fat and high protein groups is water loss. When deprived of carbohydrates the body metabolizes glycogen from the muscle and liver. For every one gram of glycogen the body stores, it must store 3 grams of water. As glycogen gets broken down water is released and excreted. In describing a case study in his book Atkins writes, "She lost 21 lbs. in the first month and I surmise that 6 or 7 lbs. of that was water weight".

However, Kekwick and Pawan felt that the weight loss could not be explained by fluid loss alone, although one wishes they had followed their subjects for a longer period. The researchers extracted a substance from the dieters' urine, which they creatively named Fat Mobilizing Substance (FMS). When they injected this into mice the experimental animals appeared to accelerate their fat burning.

In his book Atkins writes "They attributed hormonal properties to FMS. Unfortunately, their findings on FMS have never been investigated by scientists. I am hopeful that research will be underwritten that will seek to duplicate and investigate further this phenomenon. I intend to do my part, through the newly formed Dr. Robert C. Atkins Foundation."

The obvious question is this. Why hasn't Atkins funded this study long ago? He's a multi-millionaire and this would be easy work to replicate and improve. But instead, Atkins chooses to use small number, badly designed studies on which to build his theories. The 2nd obvious question is why haven't the groups such as AMA, and the American Dietetic Association replicated the research of Kekwick and Pawan and others that Atkins quotes to support his work? It would be easy to set up such studies and would show those organizations to be real truth seekers, and arm them with the data to either refute or, perhaps reluctantly, support Atkin's theories.

Later work by Rabast, Vornberger and Ehl (Ann, Nutr. Metab 25: 341-349 1981), showed similar results to those of Kekwick and Pawan. Twenty-one obese subjects were put on 3 different dietary protocols of 1340 calories for 28 days. The protocols included a high carbohydrate diet and a high fat diet. The high carb group lost 9.5 kg while the high fat group lost 12.5 kg. In their discussion they state that, "differences in energy metabolism could provide a likely explanation for the different weight reduction observed". They suggest further research. They also report that the high fat diet had "failed to exert an adverse effort on lipid values".Clearly, Dr Atkins is not completely without suggestive scientific studies in designing his diet.

One of the major criticisms and concerns about the Atkins diet is that, if followed as he prescribes, people will go into ketosis, which to a lot of people sounds like a problem. (Most words with the suffix 'osis' are not good news e.g. cirrhosis, scoliosis, halitosis, sarcoydosis, psychosis etc.) Without carbohydrates your body does not burn fat completely, and thus ketones are formed and released into the blood stream. One of the many unproven claims is that ketosis makes dieting easier as it depresses the appetite. Atkins refers to the ketosis associated with his diet as "benign dietary ketosis" as opposed to diabetic ketoacidosis, which is a medically dangerous condition.

The preponderance of evidence suggests Atkins is right. Millions of people have followed his diet and become ketotic with no apparent side effects. The successful Bernstein Health and Diet Clinics in Canada have a diet designed to put all their clients into ketosis. The major concerns usually expressed are that ketosis puts a burden on the kidneys (Atkins counsels people with kidney problems not to do his diet) and might cause leaching of calcium from the bones leading to osteoporosis. Ketosis is actually used as a form of treatment for serious epileptics as it often eliminates, or greatly reduces, seizures. These epileptic patients are kept in a state of chronic ketosis with no apparent serious side effects.

In preparation for this article I experimented with a 6 day diet of about 1000 calories which was very low in carbohydrates with caloric intake coming from very lean meat, and low glycemic index vegetables and fruits. I lost 5 lbs. When I repeated this the following week my weight loss was 2 lbs. No conclusions; this is just a personal aside, but one can see the psychological attraction of stepping on the scales after one week and being 5 lbs. lighter. In the interests of honest reporting I should also note that I was in ketosis and that I felt excellent. I should also note that I urinated a lot in the early days of the diet.

The Atkins diet is psychologically very astute. The vision of someone on an Atkins diet is of a person stopping off at Burger King™ or McDonalds™ and tucking into a double cheeseburger but this is not the reality.

The most rigorous restrictions come in the first 2-4 weeks of the Atkins regimen, the Induction Phase. This Phase is designed to put you into ketosis and to provoke rapid weight loss. During Induction you get 20 grams of carbohydrate, which comes in the form of salad and vegetables and no fruit, bread, pasta, grains, starchy vegetables, alcohol, sugar or junk. Atkins specifies no caffeine, no aspartamine and plenty of water. He also recommends wheat bran or psyllium, as constipation is a common problem of the Induction phase of his diet.

A wide range of meats, fish and eggs are allowed. Although part of the hype about the diet is that one can have bacon cheeseburgers. Atkins is careful to tell people to avoid cured and processed meats, which often add sugar and nitrates. The cheese should not be processed, and if weight loss is slow Atkins suggests no cheese at all. He also specifies no bread and to take care with the special sauce, so you could be having a bacon cheeseburger with no bun, no sauce, possibly no cheese and, if the bacon is cured with nitrates, no bacon.

Weight loss is designed to be rapid in the Induction Phase which is psychologically very important for someone who has restricted their diet and made major lifestyle changes. Atkins does not pretend the weight lost here is all fat and acknowledges that a percentage of lost weight will be water.

Phase II of the diet is OWL (ongoing weight loss). This part of the diet is still very proscribed and specific, but there is a gradual increase in carbohydrates and a reintroduction of fruit and nuts. Your reward for staying on the diet (aside from the weight loss) is increased accessibility to a wider range of foods. If weight loss continues you move on to the Pre-Maintenance Phase in which you are allowed more starchy vegetables, a wider range of fruit, plus legumes and grains. If you graduate to Lifetime Maintenance you are able to have most things in moderation. Junk food and soft drinks are still off the list and your intake of carbohydrates depends on your exercise regularity and intensity.

People envisage Atkins dieters engorging themselves on bacon, burgers and eggs benedict. He cleverly allows these on occasions so that dieters don't feel cut-off from some personal favorite, but most of his dietary recommendations for protein are for lean meat, fish and eggs. In order to lose weight you have to cut calories, which Atkins does by cutting out large amounts of carbohydrate. His entrée recipes are modest and the fifty recipes in his book average only 413 calories.

Atkins is very clear about physical activity. "Exercise is non-negotiable. If you're not getting regular exercise, you aren't following the Atkins' Nutritional Approach. It's that simple. You must make a commitment to physical activity as well as change the way you eat". Somewhat surprisingly, the September 2002 issue of Active Living criticizes the Atkins diet for "its failure to advocate physical activity." The same sentiments are stated in Nutrition News Focus, "Also, Atkins does not recommend exercise...." If we are going to be critical of Dr. Atkins, let's make sure we have our facts right. He is likewise very clear about the value of vegetables. "Let us sing the song of veggies, such beautiful, health enhancing, varied foods. They are acceptable to every cuisine worldwide and nothing in the world of cooking has more variety of taste and texture. You can get high fiber and phytochemicals with relatively low numbers of calories". (This could be Dean Ornish writing.)

I am always suspicious of people who sell their own line of vitamins and Dr. Atkins does. However, he lists what vitamins and minerals he considers important, "so you won't necessarily have to get them from Atkins Nutritionals".

In Atkins' segment on 'Disease Prevention', he writes persuasively about the value of his diet in preventing diabetes, and in the prevention of cardiovascular disease, which is contentious, as many professionals believe his diet might increase cardiovascular disease risk factors. Dean Ornish believes that people on an Atkins type diet are "mortgaging their future".

When I read the 'New Diet Revolution' I was prepared for some sensational and implausible writing. But in the context of a society struggling with obesity, the book might well have a place. Given a choice of someone staying 50 to 100 lbs. overweight or being on an Atkins diet, I'd probably go for the latter. This might not be the ideal diet in an ideal world, but it is one that seems to have appeal to many people and that works, if you stay with it. In a recent small scale Consumer Union Report, the Atkins diet was the most successful in achieving weight loss over a 6 month period.

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In its favor, the Atkins diet does provide structure which is absent from so much of the population's eating habits. After the Induction Phase, you are encouraged to eat a wide range of fruits and vegetables. Exercise is mandated throughout, as is supplementation. The diet is unbalanced and challenging to sustain, but is probably a great deal healthier than the high starch, high sugar, high fructose, high saturated and hydrogenated fat, high soft drinks, high caffeine, high preservative, high additive and high alcohol calorie intake typical of so many North Americans. Before I could confidently recommend the diet I would like answers to some of the following questions:

1. What is the success rate of the Atkins diet in promoting sustained weight loss in a large sample of people over a period of five years? (The same question should be asked of any diet.)

   This is a tall order as it is hard to find controlled studies of the Atkins diet at all, and in his 30 years Atkins himself hasn't got around to doing one. A clue to whether or not the Atkins Diet leads to long term weight loss might be found in the ongoing National Weight Control Registry Survey that is following over 3000 people who have lost an average of 65 lbs and kept if off for an average of 6 years. Their fat intake is a little over 20% of their total caloric intake on average and they consume lots of fruits and vegetables. Less than 1% of the 3000 used a high protein/high fat diet.

2. Does a high fat diet promote more fat burning than a high carb diet?

   This is the billion-dollar question and one that needs to be clarified. I doubt that this is so, especially after reading Dr. Fleming's research, which is presented later in this article.

3. Are there any measurable positive or negative changes in risk factors associated with cardiovascular disease and diabetes for people who follow the Atkins diet for an extended period?

   Atkins says there are a number of positive changes and provides some recent references. However, the references provided are not for people on Atkins' diet but for other high fat protocols. Richard Fleming's research found that the high fat diet followed by subjects in his one year study led to undesirable changes in a number of coronary risk factors. However, it must be noted that his subjects also did not specifically follow Dr. Atkins' diet.

Dr. Atkins doesn't waver in his belief. As he notes in Time 2 Sept. 2002, "For over 30 years I've been a lone voice in the wilderness. I am grateful that the National Institute of Health is now examining controlled carbohydrate and low fat nutrition. These studies may end up showing that excessive carbohydrates are the true culprits, not fat. At what point am I allowed to say, " I told you so"?

THE EFFECT OF HIGH, MODERATE AND LOW FAT DIETS ON WEIGHT LOSS AND CARDIOVASCULAR DISEASE RISK FACTORS. RICHARD FLEMING, M.D.

The most interesting recent research I could find relating to the high fat/low fat debate was Dr. Richard Fleming's publication in Preventative Cardiology Summer 2002. While the study left some questions unanswered it is worth reporting in some detail.

A total of 100 people (53 women and 47 men) were divided into 4 groups, each of which followed a different dietary protocol for one year.

The 4 dietary regimens were as follows:

1. High Fat (18 subjects) - 55-65% of caloric intake was in the form of fat calories, 25-30% of intake from protein and less than 100 g's of carbohydrates. Subjects ate until satiated. (The type and sources of fat are not specified) Of the 4 groups this would most closely resemble an Atkins diet.

2. Moderate Fat (28 subjects) - This is most similar to the diet recommended by the Surgeon General and the American Heart Association. Subjects consumed between 2000-2200 calories a day about 20-30% of which was fat.

3. Moderate Fat - Calorie Controlled (38 subjects) - Approximately 1500 calories a day. 70% carbohydrates (with an emphasis on complex carbohydrates) 15% protein and 15% fat, with no more than 5 g of saturated fat per day.

4. Low Fat (16 subjects) - 75% carbohydrates (emphasis on complex carbs), 15% protein and 10% fat. Subjects ate until satiated.

In my analysis I have focussed on the High Fat and the Low Fat groups with the Moderate Fat (Surgeon General type of diet) serving almost as a control or yardstick against which we can measure the more extreme protocols.

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	High Fat/Low Carb Caloric Restriction Diet	Low Fat/High Carb Caloric Restriction Diet	Medium Fat/Modest Nutritional Restrictions
Number of subjects	18	16	28
Average starting weight of subjects	226 lbs.	283 lbs.	243 lbs.
Caloric intake	1400-1500 cals.	1300-1400 cals.	2000-2200 cals.
Average 1 year weight loss	31.2 lbs.	52 lbs.	6 lbs.
Average weekly weight loss	0.6 lbs.	1.0 lbs.	1.9 oz.
% of weight loss	13.7%	18.6%	2.6%

% Change in Possible Coronary Risk Factors

% change in total cholesterol	4.3% increase	39.1% decrease	5% decrease
% change in LDL (bad) cholesterol	6.0% increase	52.0% decrease	6.1% decrease
% change in triglycerides	9.8% increase	45.8% decrease	5.3% decrease
% change in homocysteine	12.4% increase	11.1% decrease	9.7% decrease
% change in fibrinogen	11.9% increase	11.0% decrease	.06% decrease
Total cholesterol HDL (good) ratio	.06 increase	3.31 decrease	0.48 decrease

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