A low glycemic index diet does not affect postprandial energy metabolism but decreases postprandial insulinemia and increases fullness ratings in healthy women.
Study Goal
The researchers aimed to compare the effects of low-glycemic-index (LGI) and high-glycemic-index (HGI) diets on postprandial blood profiles, appetite sensations, energy expenditure, and energy intake in overweight women.
Results Summary
The LGI diet resulted in lower plasma glucose, serum insulin, and GLP-1 levels, higher fullness ratings, and reduced desire for fatty foods compared to the HGI diet, but no differences were observed in energy expenditure, substrate oxidation, or ad libitum energy intake.
Population
29 healthy, overweight women (age 30.5 ± 6.6 years; BMI 27.6 ± 1.5 kg/m²).
Effective Dosage
Not specified (diets matched in macronutrient composition, fiber content, energy content, and energy density).
Duration
10 weeks.
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
low glycemic index (LGI) diet | decrease | plasma glucose | healthy, overweight women | - | resulted in lower | #1 |
low glycemic index (LGI) diet | decrease | serum insulin | healthy, overweight women | - | resulted in lower | #2 |
low glycemic index (LGI) diet | decrease | plasma glucagon-like peptide (GLP)-1 | healthy, overweight women | - | resulted in lower | #3 |
low glycemic index (LGI) diet | increase | plasma glucose-dependent insulinotropic polypeptide concentrations | healthy, overweight women | - | resulted in higher | #4 |
low glycemic index (LGI) diet | increase | ratings of fullness | healthy, overweight women | slightly | were slightly higher | #5 |
low glycemic index (LGI) diet | decrease | desire to eat something fatty | healthy, overweight women | - | was lower | #6 |
low glycemic index (LGI) diet | no change | postprandial plasma GLP-2 | healthy, overweight women | - | did not differ | #7 |
low glycemic index (LGI) diet | no change | plasma glucagon | healthy, overweight women | - | did not differ | #8 |
low glycemic index (LGI) diet | no change | serum leptin | healthy, overweight women | - | did not differ | #9 |
low glycemic index (LGI) diet | no change | plasma ghrelin | healthy, overweight women | - | did not differ | #10 |
low glycemic index (LGI) diet | no change | energy expenditure (EE) | healthy, overweight women | - | did not differ | #11 |
low glycemic index (LGI) diet | no change | substrate oxidation rates | healthy, overweight women | - | did not differ | #12 |
low glycemic index (LGI) diet | no change | ad libitum energy intake (EI) at lunch | healthy, overweight women | - | did not differ | #13 |
low glycemic index (LGI) diet | decrease | postprandial glycemia | healthy, overweight women | - | were better | #14 |
low glycemic index (LGI) diet | decrease | insulinemia | healthy, overweight women | - | were better | #15 |
low glycemic index (LGI) diet | decrease | subjective appetite ratings | healthy, overweight women | - | were better | #16 |
low glycemic index (LGI) diet | no change | energy expenditure (EE) | healthy, overweight women | - | were not affected | #17 |
low glycemic index (LGI) diet | no change | substrate oxidation rates | healthy, overweight women | - | were not affected | #18 |
At present, it is difficult to determine whether glycemic index (GI) is an important tool in the prevention of lifestyle diseases, and long-term studies investigating GI with diets matched in macronutrient composition, fiber content, energy content, and energy density are still scarce. We investigated the effects of 2 high-carbohydrate (55%) diets with low GI (LGI; 79) or high GI (HGI; 103) on postprandial blood profile, subjective appetite sensations, energy expenditure (EE), substrate oxidation rates, and ad libitum energy intake (EI) from a corresponding test meal (LGI or HGI) after consuming the diets ad libitum for 10 wk. Two groups of a total of 29 healthy, overweight women (age: 30.5 ± 6.6 y; BMI: 27.6 ± 1.5 kg/m(2)) participated in the 10-wk intervention and a subsequent 4-h meal test. The breakfast test meals differed in GI but were equal in total energy, macronutrient composition, fiber content, and energy density. The LGI meal resulted in lower plasma glucose, serum insulin, and plasma glucagon-like peptide (GLP)-1 and higher plasma glucose-dependent insulinotropic polypeptide concentrations than the HGI meal (P ≤ 0.05). Ratings of fullness were slightly higher and the desire to eat something fatty was lower after the test meal in the LGI group (P < 0.05). Postprandial plasma GLP-2, plasma glucagon, serum leptin, plasma ghrelin, EE, substrate oxidation rates, and ad libitum EI at lunch did not differ between groups. In conclusion, postprandial glycemia, insulinemia, and subjective appetite ratings after a test meal were better after 10-wk ad libitum intake of a LGI compared to a HGI diet. EE and substrate oxidation rates were, however, not affected. These findings give some support to recommendations to consume a LGI diet.