How does glycemic index affect weight loss

The GI concept was first developed at the University of Toronto as a tool for the dietary management of type 1 diabetes. The GL was defined in at Harvard Medical School to account for serving size, as well as the fact that people do not generally eat single foods, but meals or snacks made up of at least two food components with different carbohydrate contents. The theory High-GL foods trigger a large rise in blood sugar, followed by a proportionate rise in insulin.

Some researchers have suggested that the unusually large rise in insulin caused by foods high in rapidly digested carbohydrates like table sugar or white bread results in weight gain for three reasons: 1 it increases enzymes that play a role in laying down fat; 2 it reduces the body's ability to burn fat for energy and 3 it increases appetite. Population studies. Researchers observed a group of healthy adults in central Massachusetts for one year and found that daily dietary GI was independently associated with body-mass index; the higher the GI, the greater the BMI.

No significant associations between GL and weight were observed in either sex. In a European study of almost 3, men and women with type 1 diabetes, researchers found that consumption of low-GI foods was related to lower body weights. An association between GI and weight has also been found in children. In a retrospective study, a group of 64 children who were instructed to eat a low-GI diet was compared with 43 instructed to eat a reduced-fat diet.

Clinical studies. In a randomized, controlled trial of overweight or obese young adults who were assigned to one of four diets classified as either high- or low-GI, those eating the low-GI diets, especially the women, experienced a greater loss of body fat than those on the higher-GI diets, despite calorie intakes being about the same.

In a review of 16 studies examining the effects of GI on appetite, all but one demonstrated an increase in satiety, delayed return of hunger or decreased food intake after eating low-GI foods, compared with high-GI foods. In a week randomized study of 45 healthy, overweight women, half were placed on a low-GI diet and half on a high-GI diet. The researchers found no significant difference between the low-GI group and the high-GI group with regard to appetite or body-weight regulation during the study.

Whether or not these diets are effective for weight loss may vary from person to person and may depend on whether the person is insulin-resistant having a diminished ability to respond to insulin.

Individuals who are insulin-resistant experience a much higher rise in insulin than others eating the same amount of carbohydrate. One six-month study of 32 healthy, overweight men and women found that a low-GL diet aided weight loss in those who had relatively high insulin levels after eating sugar, whereas those who had relatively low insulin levels did not have greater weight loss on the low-GL diet.

Animal studies. Rats fed a high-glycemic index diet for three weeks exhibited significant physiological changes compared with rats fed a low-glycemic index diet, including an increase in fatty acid synthase, an enzyme responsible for depositing fat. Overcooking pasta greatly increases the GI. Even the ripeness of fruit affects its GI. A food with a GI lower than 55 is considered a low-GI food; more than 70 is considered high when compared to glucose as the reference food.

The diets For any diet, the less-processed the food, the lower the GI is likely to be. However, if the diet is high in carbohydrates or serving sizes are large, the GL may be higher, even if the diet consists mainly of high-fiber fruits, vegetables and whole grains. Generally speaking, a low-GL diet should provide portion-controlled servings of whole fruits, vegetables, whole grains, beans, legumes, nuts and seeds and provide a source of lean protein at each meal or snack.

Refined carbohydrates like those in white bread, white flour, baked goods and highly processed packaged foods should be restricted or eliminated. People striving to eat a low-GL diet should aim for meals with a GL of 20 or less; each snack should have a GL of 10 or less. Adding noncarbohydrate foods and beverages such as animal protein, vegetables, fats, oils, nuts and seeds will not affect the GL.

Ornish's plan is a very-low-fat, high-carbohydrate plan. And despite the results of some negative studies, the preponderance of evidence suggests a positive benefit.

Another question yet to be answered is whether people with already elevated insulin levels might benefit the most from such diets. The first in a two-part series. Click here for part II. The GI of a high-carbohydrate food like rice changes depending on what you mix with it; the GL of a meal varies depending on what else you put on the plate. Foods with few or no carbohydrates—such as beef, chicken, fish, eggs, avocadoes, butter and oil—have no GI values.

References 1. Bell SJ, Sear B. Low-glycemic-load diets: impact on obesity and chronic diseases. Crit Rev Food Sci Nutr ;43 4 Pereira MA.

Weighing in on glycemic index and body weight. Am J Clin Nutr ;? Jenkins DJ, et al. Glycemic index of foods: a physiological basis for carbohydrate exchange. Salmeron J, et al. Dietary fiber, glycemic load, and risk of non-insulin-dependent diabetes mellitus in women.

J Am Med Assoc ;? Ludwig DS. Glycemic load comes of age. J Nutr ;? Nutrition Australia. The Glycemic Index Symbol Program. Pawlak DB, et al. As such, the glycemic load provides a more real-world perspective on how much consuming a given serving of food will impact your blood glucose. Even though the glycemic load provides additional information, there are still shortcomings of glycemic load.

For example, glycemic load is often highly reflective of an individual's fiber content, wherein lower glycemic load diets are higher in fiber. This makes it difficult to discern whether or not the glycemic load as a measure is any more valid than simply tracking fiber intake. Additionally, While both the glycemic index and glycemic load measures can provide some value, there is one glaring issue with both measures: they fail to take personal variances into account. While it was speculated that there might be slightly different responses between two people to a given food, recent research has shown that these differences are quite substantial Zeevi et al.

Furthermore, in the same study, they found that the participants all had very different responses to a single serving of bread. One participant showed virtually no glycemic response, and others showed a very high glycemic response Zeevi et al. Low-glycemic diets have been promoted as promising tools for weight loss. There is some evidence to suggest that following a low-glycemic diet may indeed help with weight loss Juanola-Falgarona et al.

However, it appears as though it is not necessarily the fact it is low-glycemic, but the other properties of the diet e. As such, do not lean heavily on the glycemic index as driving when selecting a diet. The glycemic index provides a rough estimation of how much an individual food may increase blood glucose after consumption.

This index may provide some utility as a rough guideline for individuals to understand how their bodies respond to a given food. However, it is essential to understand the total amount of carbohydrates consumed as well, which is more reflected in the glycemic load measure. However, both measures are crude estimates and fail to take individual variation into account, which recent evidence has shown to be relatively high.

It is best to think of the glycemic index as a rough tool to help guide some decisions but is not a highly accurate tool that should drive all nutrition decisions. He received his B. Is there a dose-response relation of dietary glycemic load to risk of type 2 diabetes? Meta-analysis of prospective cohort studies. Am J Clin Nutr ; 97 : — Arch Intern Med ; : — 7. Glycemic index, glycemic load and cancer risk. Ann Oncol ; 24 : — European Food Safety Authority. EFSA J ; 8 : Glycaemic index effects on fuel partitioning in humans.

Obes Rev ; 7 : — Livesey G. Low-glycaemic diets and health: implications for obesity. Proc Nutr Soc ; 64 : — Glycaemic response to foods: impact on satiety and long-term weight regulation. Appetite ; 49 : — Dietary strategies to increase satiety. Adv Food Nutr Res ; 69 : — Metabolism ; 58 : — Consumption of a legume-enriched, low-glycemic index diet is associated with biomarkers of insulin resistance and inflammation among men at risk for colorectal cancer.

A low-glycemic load diet reduces serum C-reactive protein and modestly increases adiponectin in overweight and obese adults. J Nutr ; : — A low-glycemic index diet and exercise intervention reduces TNF alpha in isolated mononuclear cells of older, obese adults. Effects of weight loss and long-term weight maintenance with diets varying in protein and glycemic index on cardiovascular risk factors: the diet, obesity, and genes DiOGenes study: a randomized, controlled trial.

Circulation ; : — Nutr Hosp ; 28 : — Stages of change across ten health risk behaviors for older adults.

Gerontologist ; 39 : — International tables of glycemic index and glycemic load values: Diabetes Care ; 31 : — 3. Diet and lifestyle recommendations revision a scientific statement from the american heart association nutrition committee.

Circulation ; : 82 — Validation of the minnesota leisure time physical activity questionnaire in spanish women. Med Sci Sports Exerc ; 32 : — 7.

Homeostasis model assessment: insulin resistance and beta-cell function from fasting plasma glucose and insulin concentrations in man. Diabetologia ; 28 : — 9. Paris, France : Lavoisier , in French. Google Preview. Adjustment for total energy intake in epidemiologic studies. A randomized trial comparing a very low carbohydrate diet and a calorie-restricted low fat diet on body weight and cardiovascular risk factors in healthy women.

J Clin Endocrinol Metab ; 88 : — Energy-restricted diets based on a distinct food selection affecting the glycemic index induce different weight loss and oxidative response. Clin Nutr ; 27 : — Low glycaemic index or low glycaemic load diets for overweight and obesity.

Schwingshackl L , Hoffmann G. Nutr Metab Cardiovasc Dis ; 23 : — Dietary composition and weight loss: can we individualize dietary prescriptions according to insulin sensitivity or secretion status?

Nutr Rev ; 64 : — Effect of low- and high-glycemic load on circulating incretins in a randomized clinical trial. Metabolism ; 62 : — Total and undercarboxylated osteocalcin predict changes in insulin sensitivity and beta cell function in elderly men at high cardiovascular risk. Am J Clin Nutr ; 95 : — Effect of a low-fat versus a low-gycemic-load diet on inflammatory biomarker and adipokine concentrations. Metab Syndr Relat Disord ; 10 : — Oxford University Press is a department of the University of Oxford.

It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide. Sign In or Create an Account. Sign In. Advanced Search. Search Menu. Article Navigation. Close mobile search navigation Article Navigation. Volume Effect of the glycemic index of the diet on weight loss, modulation of satiety, inflammation, and other metabolic risk factors: a randomized controlled trial. Oxford Academic. Antoni Rabassa-Soler. Rafael Balanza. E-mail: monica.

Select Format Select format. Permissions Icon Permissions. ABSTRACT Background: Low—glycemic index GI diets have been proven to have beneficial effects in such chronic conditions as type 2 diabetes, ischemic heart disease, and some types of cancer, but the effect of low-GI diets on weight loss, satiety, and inflammation is still controversial.

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