Syndrome X - Overcoming the Silent Killer That Can Give You a Heart Attack
by Gerald Reaven 2000
Dr. Gerald Reaven made his reputation in researching carb sensitivity experienced by 25-30% of the population. According to Dr. Reaven, excess insulin in the bloodstream acts like an abrasive, leading to cholesterol deposits on the arteries. He attributes as much as 50% of all heart attacks to Syndrome X.
Dr. Reaven started looking into "insulin resistance" long before gaining popular support, and seems to guard his territory zealously. In 1988 he named Syndrome X and described an elusive cluster of symptoms: slightly elevated glucose levels, compensatory hyperinsulinemia, elevated blood triglycerides, low HDL cholesterol, and/or high blood pressure. Since then, he added dense LDL particles, slow clearing of blood fats after meals, and poor ability to break up blood clots.
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Dr. Reaven provides a useful benchmark for elevated glucose. He says that blood glucose will go up to 140 mg/dl after a meal and drop to back down within 2 hours for a normal person. "But in an insulin-resistant person with glucose intolerance, blood sugar might go as high as 160 mg/dl after a meal, and perhaps take 30 minutes longer to return to the pre-meal level."
The self-assessment scorecard on page 68 includes the following information. If your fasting glucose level is greater than 110 mg/dl, or your glucose tolerance test (75 gm glucose) is greater than 140 mg/dl after two hours, you have Syndrome X tendencies. Likewise, if your fasting triglyceride level is greater than 200, if your HDL is lower than 35, if your blood pressure is greater than 145/90, and/or if you're more than 15 pounds overweight, then you have Syndrome X tendencies.
Page 96 has a clever formula for establishing your daily calorie requirements. If you are inactive, you multiply your weight by 14. For moderately active, multiply by 15, and for fairly active, multiply by 16. Therefore a 150-lb. person would need 2100, 2250, or 2400 calories per day according to this formula. Not an ideal formula, because it ignores lean body mass, but quick.
Reaven adheres to the "calories in, calories out" school of thought on weight gain and loss. He insists that excess insulin production does not automatically produce weight gain if one exerts will-power over "calories in." The relatively high fat intake of his diet could quell the appetite, so perhaps the carb-sensitive person can adhere to his dietary program. (However, does Dr. Reaven's rationale take into account the weight of calorie-free water?)
Dr. Reaven recommends a Protein 15%, Carbohydrate 45%, Fat 40% balance of macronutrients, with the greater proportion of fats consisting of unsaturated fats. He argues that people who normally eat more carbohydrates can shift consumption over to increased "healthy" fats. This shift of calories to fat reduces insulin production and makes for healthier arteries.
He points out that a high carb-low fat diet can actually worsen health for Syndrome X'ers and contribute to a heart attack. On the other hand, he advises against the Protein 30% recommended by the Zone diet because "protein also increases insulin secretion." He claims that it is "difficult to eat all the suggested protein without taking in a lot of saturated fat in the process," and that the excess fat will elevate LDL cholesterol. He considers his own recommendation of Protein 15% "safer."
On page 77 Dr. Reaven displays a table showing that only his Syndrome X Diet decreases both insulin and LDL cholesterol. The American Heart Association, The Zone Diet, and Atkins Diet are included.
The table makes a flat-out error in stating that the Zone diet does not decrease both insulin and LDL cholesterol. Apparently Dr. Reaven has not read the Zone books which recommend monitoring TG/HDL ratio, an indirect marker of insulin production. Nor is he aware of testimonials citing reduction of LDL cholesterol on the Zone diet.
On page 91 Dr. Reaven writes, "Unfortunately Protein Power, The Zone and other pop diet and weight loss books have hijacked and badly mangled the research we've conducted at Stanford University. Their interpretation of our research findings is more fiction than fact."
Dr. Reaven may be the reigning authority on the precise definition of insulin resistance, but he himself has difficulty presenting the facts of balanced nutrition. While his general prescription is generally healthy, his presentation contains some blatant oversights.
Apparently Dr. Reaven has never heard of the glycemic index, pioneered in the early 1980's. No such item or similar item can be found in the index of his book. His text makes no distinction whatever between different carbohydrates. Apparently the 81 calories in two teaspoons of sugar are equivalent to the 81 calories in four cups of raw broccoli. His recipes look healthy, but his text doesn't examine the way highly refined carbs differ from whole vegetables and fruit.
A book called "The Glucose Revolution," published in 1996, describes how the quality of carbohydrate affects the total increase of blood sugar after a meal. By consulting this book, the reader can estimate the glucose load of a given meal, whether it be made of low-glycemic natural food or high-glycemic pastry.
Apparently Dr. Reaven has not read "Dr. Bernstein's Diabetes Solution, A Complete Guide to Achieving Normal Blood Sugars," published in 1997. Dr. Bernstein pioneered the use of the first portable glucometers (also in the early 1980's), thus enabling Type 1 diabetics to live full lives. He describes the trial and error process he went through in selecting vegetables as his carbohydrates of choice in maintaining predictably healthy levels of blood sugar.
Both "The Glucose Revolution," and "Dr. Bernstein's Diabetes Solution, A Complete Guide to Achieving Normal Blood Sugars," clearly describe dietary prescriptions for eliminating Syndrome X symptoms: high-quality, low-glycemic carbohydrates.
Dr. Reaven should have mentioned that oatmeal, legumes, and fiber reduce LDL cholesterol, one of the markers of Syndrome X. He did not include warnings about artificial sweeteners or recommend the herb Stevia in their place. His dietary plan ought to point out the dangers of carbohydrate-dense convenience foods and their additives.
Besides the oversights in the text about carbohydrates, Dr. Reaven makes a curious presentation about fats. He separates out the "bad" saturated fats like butter and says they should be limited to 5% or 10% of the total diet. Then he examines hydrogenated vegetable oils and advises that some margarines with small quantities of trans-fats may be better than butter, since vegetable oil represents the major part.
Additionally, Dr. Reaven regards both safflower oil and olive oil as "good" fat, making no real distinction between them. By lumping polyunsaturated fats (vegetable oils) and monounsaturated fats (olive oil) together, he overlooks research showing the importance of balancing Omega 6 and Omega 3 fatty acids. Dr. Reaven should have stressed the importance of limiting (not eliminating) the consumption of vegetable oil, for optimal metabolism.
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Dr. Reaven takes his turn to set the record straight and explain the "insulin resistance" affecting 25%-30% of the population on his own terms. But has he converted his research into a practical health manual, given the oversights of his text? The P15, C45, F40 diet makes sense, but the presentation on carbohydrates and fats needs some tweaking. After additional revision of the presentation, would his diet contain the same macronutrient ratios?
Dr. Reaven also has some difficulty describing his concept consistently. He refers to Syndrome X as a "complicated disorder," and "more than a disease with a single cause." Yet he reassures the reader, "...you can defeat the disease by making lifestyle changes ."
Dr. Reaven's point can be stated simply. Carb-sensitive people compromise their health and risk heart trouble when they eat the wrong foods. To avoid these problems, they should eat a properly balanced diet and stay physically active. |