Processed Carbohydrates, Dr. Atkins, and the Fallacy of Merely Measuring Food on the Glycemic Index

In Atkins for Life Dr. Atkins addresses the dangers of processed carbohydrates:
When you eat a highly refined carbohydrate food like a sugary cereal, it is quickly converted to glucose so it rushes into your bloodstream almost at once. The result is a glucose spike, followed by a glucose drop—it's called unstable blood sugar. Eat an unprocessed carbohydrate food that is lower in sugar and contains a lot of fiber, like berries, and what happens? The amount of glucose from the food enters your bloodstream slowly and steadily. No glucose spike, and no sudden glucose drop—your energy stays on an even keel. That's because the sugar in the berries is in the form of fructose, which must be converted to glucose in your liver. That takes some time, and the process is slowed down even more by the fiber in the berries. And when your glucose levels stay constant, there is no need to send in the heavy artillery in the form of additional insulin to deal with transporting excess glucose to your cells.
Now, Dr. Fuhrman does agrees that processed carbohydrates are detrimental to human health, but he takes issue with the Atkins rationale. He explains:
Atkins’ explanation of the quick rise and fall of glucose is not the reason that accounts for the problem with refined foods. There are reasons why high glycemic foods may be harmful but just explaining they are high glycemic is not one of them. It is true that a high glycemic response is one of the many features that is present in unhealthy processed foods, but that response is not a significant reason that explains the problem with those foods. There is no reason the glucose and insulin curve must stay blunted for good health. In diabetes research the glycemic index (GI) of carbohydrates has long been recognized as a favorable aid for diabetics to control blood sugar. The same is now often the case in lipid research as it has been demonstrated that high glycemic diets, rich in white flour, refined sweets and processed foods are unfavorable to both glucose levels and lipid parameters. The glycemic index of these foods is not the main reason they are dangerous foods, the main reason is because they are missing nutritional value.

Authors and writers who advocate a high protein (meat-based) diet, hang their hat on the low glycemic index of animal products to explain the advantages of a diet rich in animal products and lower in vegetation. This view oversimplifies the multi-factorial nuances of human nutrition and this results in a distorted understanding of nutritional science. Ranking food on the glycemic index alone ignores many other factors that may make that food favorable or unfavorable. Because a carrot has a higher glycemic index than a slice of bacon does not make the bacon a better food for a diabetic or heart patient. There are other more important nutritional considerations besides the glycemic index, including the toxicity, micronutient density, and fiber in the food. .

A good example of such nutritional nonsense is when Barry Sears (of the Zone diet), warns against the consumption of lima beans, papayas, and carrots because of their glycemic index and Atkin’s excludes or limits those carbohydrate containing fruits and vegetables with proven powerful anti-cancer benefits. The studies that have looked at the negative effects of a higher glycemic diet are always diets with low-nutrient, low fiber, processed grains, and sweets whose negative aspects are not limited to their glycemic response. Processed foods are also low in fiber, phytonutrients, and anti-oxidants and rich in those toxic acrlyamides; they are disease-promoting foods and one of their features is that they also have a high glycemic index.

When a diet is rich in high nutrient containing, vegetables, beans, nuts, seeds, and fresh fruits the disease-protective qualities of these foods and the weight-loss benefits overwhelm any insignificant drawback from the high glycemic index of the carrot. Recently, systematic review was performed of published human intervention studies comparing the effects of high- and low-GI foods or diets on appetite, food intake, energy expenditure and body weight; in a total of 31 short-term studies. The conclusion was that there is no evidence that low-GI foods are superior to high-GI foods in regard to long-term body weight control. More carefully performed research done recently compared the exact same caloric diets one with a lower and one with a higher glycemic index and demonstrated that lowering the glycemic load and glycemic index of weight reduction diets does not provide any added benefit to energy restriction in promoting weight loss in obese subjects.

The bottom line, is H = N/C. A diet-style rich in phytonutrients and low in animal protein will resolve your cravings, and hypoglycemic signals. Almost all authors make some worthwhile points, but when the application of their recommendations allows people to die prematurely of heart disease or cancer, I do not condone positioning them as a nutritional authority. Atkin’s has a history of dangerous and fraudulent statements that has injured the health and likely shortened the lives of thousands of people.


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NY Times On Negative Calorie Diets

Most people probably haven’t heard of “negative calorie” diets, the claim that certain foods (like celery and lettuce) contain so few calories that you expend more energy chewing and digesting them than they actually provide. Anahad O’Connor of The New York Times contends this claim is based on inexact science:
Topping the list of “negative calorie” foods are vegetables like cabbage, lettuce, cucumbers and celery. Celery, for example, contains 8 to 10 calories a stalk and is 95 percent water.

Chewing most foods typically only burns about five calories an hour, but the act of digesting may require slightly more. That is particularly the case with celery because it is mostly cellulose, a type of fiber that humans do not have the enzymes necessary to properly break down and use.

Cathy Nonas, director of obesity and diabetes programs at North General Hospital in Harlem, said that while no hard studies exist, it is possible that snacking on celery might cause a very slight calorie deficit. But the difference would be so minuscule that at the end of the day it would have no real impact unless the celery was replacing other fattening or high calorie foods. The other problem is that celery is not only low in calories, but also low in vitamins and minerals.
Check out the video that accompanies the report: Are Negative Calories for Real?

Healthy Eating, Diet and Fitness Blog Carnival #3

Healthy Eating, Diet and Fitness Blog Carnival #2