Eating By The Book
by Monika Klein, C.N.
Despite the shifting focus from thinness to fitness, we are still a society obsessed with weight. Here, clinical nutritionist Monika Klein summarizes the health-and-fitness sense of some of the most popular diet plans.
Weight loss is not the only reason people diet, but it is the most common. While people also diet for freedom from chronic disease, to sustain energy and to encourage a positive attitude, Hollywood has created the most toxic reason to diet — false image. Unrealistic expectations can lead to serious conditions such as anorexia nervosa or bulimia.
Added to the mix is a multibillion-dollar diet industry that has many of us feeling conned and confused. Pills, packaged foods and eating programs are alluring to our fast-food, instant-gratification culture. Sure, you want quick and easy ways to lose weight. Unfortunately, too often people attach so much importance to dieting that it leaves them in emotional, physical and spiritual pain. All of my clients have stories about a diet that worked for a friend. And they think maybe it will work for them, too.
The truth is many diets work for many people, but the ideal diet must be tailor-made for each individual. Sensible diets contain fruits and vegetables, less saturated fats and fewer total calories. What differentiates most diets from each other are the proportions of carbohydrates, protein and fat they contain.
The following diets are among the more popular plans being sold in bookstores today. If you're looking for a diet to accommodate your health needs, these summaries will give you a starting place.
The "Balanced" Theories
Both the Blood-Type and the Zone diets advocate maintaining health by eating a balanced ratio of carbohydrates, proteins and fats. Overall, foods contained in the Blood-Type diet represent a balanced ratio but vary widely depending on one's blood type. The Zone popularized the 40/30/30 ratio of carbohydrates, protein and fat and is a good maintenance diet because it contains a variety of essential vitamins and minerals, with a nutrient balance to stabilize blood sugar.
Blood-Type Diet
The diet popularized by naturopathic doctor Peter D'Adamo's book Eat Right 4 Your Type (G.P. Putnam's Sons) bases food choices on the blood types O, A, B and AB.
Type O blood is regarded by anthropologists as the oldest human blood type. People with type O blood, according to D'Adamo, had hunter-gatherer ancestors and do well eating meat. They have enough hydrochloric acid (HCl) in their stomachs to digest meat proteins.1 Because neither dairy products nor grains such as wheat and corn became staples until later in human evolution, D'Adamo theorizes the digestive systems of those with type O blood never adapted to them.
D'Adamo believes people with type A blood descended from those who developed agriculture and grain cultivation, and therefore are fine candidates for diets based on grains and vegetables. Unlike people with type O blood, D'Adamo says they do not have enough HCl to digest meats and are more suited to fish and tofu.
People with type B blood are descended from herdsmen, explains D'Adamo, and they do well eating dairy — unlike both O and A types. The rarest type is AB, which he believes the human species will eventually evolve into. People with type AB blood can eat a bit of everything.2
D'Adamo also says certain health conditions are blood-type specific — although blood type is more of a guideline than the sole determining factor.
I have seen success with this diet in my practice: People have lost weight, cleared sinus conditions, improved bowel function, balanced blood sugar and, perhaps most importantly, they feel better.
As with any diet, however, compliance is always a problem. This diet can be difficult to adhere to and can get quite specific — for example, D'Adamo recommends staying away from certain types of onions and cabbage. Although some people lose weight on this diet, it is better suited to people interested in clearing up existing health conditions such as arthritis or allergies, and maintaining their health.
The Zone
Barry Sears, Ph.D., first introduced the balance concept several years ago when he published his book The Zone (ReganBooks).
Sears proposes that excessive carbohydrates are to blame for the fattening of America, a theory unheard of at the time by most diet and nutrition experts and certainly the general population. It is commonly held that pasta, rice cakes and bagels are health foods, not high-glycemic foods that adversely affect health. Sears says otherwise, and studies have confirmed this.3
He advises people who wish to lose weight to balance carbohydrates, protein and fat intake to a 40/30/30 ratio. This is a significant change from the previous conventional wisdom of a 60/20/20 ratio, which minimized protein and fats because they are associated with some of the most debilitating diseases such as cancer and heart disease. As Sears points out, concurrent with the 20-year-old war on fat is a rise in diabetes and insulin resistance. He says this is primarily due to high-carbohydrate, low-fat diets that increase insulin.4,5 Unlike diets that restrict calories, the Zone balances hormones.6
Most of Sears' studies have been done with a large HMO patient base and results show the Zone's effectiveness. Sears claims the Zone is an anti-aging, calorie-restricted program. Countless animal studies show that calorie restriction — but not malnutrition — results in longer and healthier lives.7
One drawback is that, even though most people lose weight on this diet, its calorie restrictions leave people hungry, especially those who are physically active. This is a sound diet because it promotes balance, but some may find following the exact portions difficult. Also, since it advocates eating meat, it is problematic for vegetarians.
High Carbohydrate/Low Fat
Both the Life Choice program and the McDougall program qualify as low-fat, vegetarian diets. One small but potentially meaningful difference is that the Life Choice program recommends fish-oil supplements, while the McDougall program is strictly vegan — no animal products whatsoever.
The Life Choice Program
Developed by Dean Ornish, M.D., and explained in his book Eat More, Weigh Less (Harper Paperbacks), this plan could be classified as the fat-phobic diet. Many have lost weight with this diet,8 but it won't work for everyone.
It is low in protein and fat, including essential fatty acids, as well as low in several micronutrients such as vitamin B12 and zinc, which tend to come from animal products. Although the book does not specify ratios per se, I would estimate it as 75 to 85 percent carbohydrates from grains, legumes, fruits and vegetables; 5 to 10 percent fat; and 10 to 15 percent protein from grains, legumes, nuts and seeds.
Anyone following this diet long term should increase the fat amount, especially women because inadequate fat consumption can affect a woman's hormone levels.9 Ornish contends that the biggest nemesis in our diets is saturated fats.10 He does support the use of 2 grams a day of fish oil — the exception to the vegetarian rule — and 2 grams a day of flaxseed oil (a polyunsaturated fat) to provide essential omega-3 fatty aids.
This fiber-rich diet restores proper elimination and is a good cleansing diet. Many of Ornish's results have been published in the Journal of the American Medical Association, and his program has become the accepted way to treat weight loss and even serious illnesses such as heart disease, hypertension and cancer.
The mind/body aspect of this diet is quite valuable. Much of Ornish's program is lifestyle-enhancing, whereby participants are encouraged not only to change eating habits but also to exercise, meditate, and become involved with group therapy and stress management. In my clinical experience, emotional support is often the most important aspect of dieting, yet it is commonly overlooked.
McDougall Program
This short-term plan, popularized in the book McDougall Program for Maximum Weight Loss (NAL/Dutton) by John A. McDougall, M.D., is high in some fruits as well as starches such as beans, corn, potatoes and rice.
The carbohydrate/protein/fat ratio is not itemized, but I would classify it as 80 to 90 percent carbohydrates and only 10 to 20 percent protein and fat. There is no doubt that anyone following this program will quickly lose weight. For most, this diet is a way to get off junk food and highly processed foods. Like Ornish, McDougall also focuses on perceived toxic effects of animal products. Without these foods the diet becomes a cleansing diet as well.
I would call this extreme plan a food-phobic diet. Although most diets tout the benefits of calorie restriction, this program is severe and could lead to lean wasting and other complications. Endocrine-system dysfunction, for example, may occur because of the low amounts of essential fatty acids, which can create hormonal imbalances.11 Lean wasting occurs when lean muscle mass is lost rather than fat.
In addition, many people in my clinic who have tried the McDougall program became bored with the food restrictions, and gained the weight back shortly after discontinuing the program. This eating plan also lacks some essential amino acids and essential fatty acids.
However, this diet could be appropriate for five to seven days. It would help a person make smarter food choices and eliminate highly processed foods.
High Fat, High Protein, Low Carbs
A low-fat diet will shed body fat, right? Not so, according to the Atkins diet, which says obesity exists for metabolic reasons, and bypassing carbohydrates is the proper path to weight loss.
The Atkins Diet
Developed by Robert Atkins, M.D., and detailed in the book Dr. Atkins' New Diet Revolution (Avon Books), this program encourages weight loss and health gain through a process called ketosis, which basically forces the body to use stored body fat as fuel rather than metabolized carbohydrates from the daily diet.
The premise of this diet is to eat a lot of fat and protein and very few carbohydrates, which puts the body in a state of ketosis and thereby increases metabolism, decreases hunger and balances blood sugar.
Initially, protein and fat ratios are approximately 95 percent and carbohydrates are only 5 percent. This is called the induction phase, and it lasts about two to four weeks. Once adequate weight loss is achieved, a maintenance level is begun and ratios change to 75 to 85 percent protein and fat and 15 to 25 percent carbohydrates.
Studies show a "significant" energy-level increase and weight decrease among people following the Atkins diet.12 It also seems to balance blood sugar in diabetics and hypoglycemics.13 The plan shows beneficial results with insulin and glucose balance by reducing carbohydrate consumption and increasing protein and fat consumption.
Some experts and practitioners, however, question the excessive amounts of fat and protein recommended. Most people, though, could benefit by eating fewer refined carbohydrates.14 Even so, high protein can cause its own set of problems such as impaired kidney function.15 Atkins believes the diet is safe as long as a person's creatinine blood levels (a measure of kidney disease) stay below 3.0 (1.2 is considered normal), but he recommends anyone following the diet be monitored by a physician. Constipation often results from insufficient plant fiber from grains, fruits and vegetables, so a fiber supplement is suggested.
I disagree with Atkins' theory that "almost any fat will do," because healthier fats and oils do not increase the risk of chronic illnesses such as heart disease and arthritis. This diet does, notably, steer away from more artificial fats such as margarine. Finally, because the diet calls for large quantities of protein from meat, this is clearly not a plan for vegetarians.
The Diet For You
Especially in the next 20 years, baby boomers concerned about degenerative diseases and aging may start thinking about eating well and taking better care of themselves.
Remember that each person is unique. Bioindividuality is key in any diet plan and not all techniques work for everyone. Every diet has its success stories as well as its critics. Ultimately, the only thing that counts for each person is results. Perhaps the best advice for those who wish to eat well, especially those with specific health concerns, is to work with a qualified health care practitioner.
Regardless, the basics still apply: Eat a balanced diet of fresh, wholesome foods including carbohydrates, protein and proper fats; supplement appropriately; and get plenty of daily exercise — something you like and even love to do, so you'll stick with it. In the end, we need to eat and do what makes us feel good.
Monika Klein, C.N., runs a nutritional counseling practice in Malibu, Calif., and is the television host of Total Health Talk.
References
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2. Sheppard PM. Blood groups and natural selection. Brit Med Bull 1959;15:132-9.
3. Lane MA, et al. Dehydroepiandrosterone sulfate: biomarker of primate aging slowed by calorie restriction. J Clin Endrocrinol Metab 1997;82:2093-6.
4. Slabber M, et al. Effects of a low-insulin-response, energy-restricted diet on weight loss and plasma insulin concentrations in hyperinsulinemic obese females. Am J Clin Nutr 1994;60:48-53.
5. Scheen AJ, et al. Effects of metformin in obese patients with impaired glucose tolerance. Diabetes Metab Rev 1995;11:69S-80S.
6. Zavaroni I, et al. Hyperinsulinaemia, obesity and syndrome X. J Int Med 1994;235:51-6.
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8. Kendall A, et al. Weight loss on a low-fat diet: consequences of the imprecision of the control of food intake in humans. Am J Clin Nutr 1991;53:1124-9.
9. Brush MG, et al. Abnormal essential fatty acid levels in plasma of women with premenstrual syndrome. Am J Obstet Gynecol 1984 Oct 15;150(4):363-6.
10. Ornish D. Dietary treatment of hyperlipidemia. J Cardiovasc Risk 1994;1:283-6.
11. Kretsch MJ, et al. Vitamin B-6 requirement and status assessment: young women fed a depletion diet followed by a plant- or animal-protein diet with graded amounts of vitamin B-6. J Am Clin Nutr 1995;61:1091-1101.
12. Tremblay N, et al. Nutritional determinants of the increase in energy intake associated with a high fat diet. Am J Clin Nutr 1991;53:1134-7.
13. Lovejoy JC, et al. Effect of a controlled high-fat diet on insulin sensitivity and leptin levels in African-American and Caucasian women. Metabolism 1998 Dec;47(12):1520-4.
14. Laino, C. Transfatty acids in margarine can increase MI risk. Circulation 1994;89:94-101.
15. Klarhr S, Levey G. The effects of dietary protein restriction and blood pressure control on the progression of chronic renal disease. New Eng J Med 1994;330:877-84.
