Do low glycemic index diets increase insulin sensitivity in overweight or obese patients?

The relationship between intramyocellular (IMCL) and extramyocellular lipid (EMCL) accumulation and skeletal muscle insulin resistance is complex and dynamic. We examined the effect of a short-term (7-day) low-glycemic index (LGI) diet and aerobic exercise training intervention (EX) on IMCL and insulin sensitivity in older, insulin-resistant humans. Participants (66 ± 1 yr, BMI 33 ± 1 kg/m2) were randomly assigned to a parallel, controlled feeding trial [either an LGI (LGI/EX, n = 7) or high GI (HGI/EX, n = 8) eucaloric diet] combined with supervised exercise (60 min/day, 85% HRmax). Insulin sensitivity was determined via 40 mU·m−2·min−1 hyperinsulinemic euglycemic clamp and soleus IMCL and EMCL content was assessed by 1H-MR spectroscopy with correction for fiber orientation. BMI decreased (kg/m2 −0.6 ± 0.2, LGI/EX; −0.7 ± 0.2, HGI/EX P < 0.0004) after both interventions with no interaction effect of diet composition. Clamp-derived insulin sensitivity increased by 0.91 ± 0.21 (LGI/EX) and 0.17 ± 0.55 mg·kg−1·min−1 (HGI/EX), P = 0.04 (effect of time). HOMA-IR was reduced by −1.1 ± 0.4 (LGI/EX) and −0.1 ± 0.2 (HGI/EX), P = 0.007 (effect of time), P = 0.02 (time × trial). Although both interventions increased IMCL content, (Δ: 2.3 ± 1.3, LGI/EX; 1.4 ± 0.9, HGI/EX, P = 0.03), diet composition did not significantly effect the increase. However, the LGI/EX group showed a robust increase in the [IMCL]/[EMCL] ratio compared with the HGI/EX group (Δ: 0.5 ± 0.2 LGI/EX vs. 0.07 ± 0.1, P = 0.03). The LGI/EX group also demonstrated greater reductions in [EMCL] than the HGI/EX group (Δ: −5.8 ± 3.4, LGI/EX; 2.3 ± 1.1, HGI/EX, P = 0.03). Changes in muscle lipids and insulin sensitivity were not correlated; however, the change in [IMCL]/[EMCL] was negatively associated with the change in FPI ( r = −0.78, P = 0.002) and HOMA-IR ( r = −0.61, P = 0.03). These data suggest that increases in the IMCL pool following a low glycemic diet and exercise intervention may represent lipid repartitioning from EMCL. The lower systemic glucose levels that prevail while eating a low glycemic diet may promote redistribution of lipid stores in the muscle.

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Consumption of Insoluble Fiber Boosts Insulin Sensitivity in Obese Patients

Family Practice News ◽

10.1016/s0300-7073(06)73191-7 ◽

2006 ◽

Vol 36 (10) ◽

pp. 24

Author(s):

SHERRY BOSCHERT

Keyword(s):

Insulin Sensitivity ◽

Obese Patients ◽

Insoluble Fiber

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THE recipe modification of sugar-free bakery goods for reducing glycemic index and enhancing the nutrition and functional features

International Conference on Technics Technologies and Education ◽

10.15547/ictte.2019.07.028 ◽

2019 ◽

pp. 463-468

Author(s):

Nataliia Sokolova

Keyword(s):

Glycemic Index ◽

Metabolic Disorders ◽

Healthy Lifestyle ◽

Optimum Ratio ◽

Medical Problems ◽

Rye Flour ◽

Lentil Flour ◽

Functional Features ◽

Baked Products ◽

Low Glycemic Index

Wheat flour-based products are the most popular and desirable of all bakery goods. In the same time, they give the heights glycemic response so this type of products are banned for people with metabolic disorders as well as consumers who have a tendency to live a healthy lifestyle. In the same time the increasing consumption of sugars has resulted in several nutritional and medical problems, such as obesity, diabetes, and cardiovascular diseases. The uses of a combination of various ingredients in range (such as rye flour – 40...60, dry gluten – 5...15, oat dietary fibre – 1...6 % and lentil flour - 5...20 %) that may modify the glycemic index of baked products, enhance the nutrition and functional features have shown in the article. Water Stevia extract demonstrated no effect on the baking quality and suggested the use of it to improve palatability and nutritional properties of developed new sugar-free bakery products. It was found the optimum ratio of these ingredients as a result of a series of studies and processing of the obtained data by multicriteria optimization. Results have shown that lentil flour can be used in the amount 12.5 % for the achieving optimum ratio "low glycemic index-high taste". It is shown that due to lentil flour it is possible to reduce the glycemic index to a greater extent than rye flour, dry gluten, but in terms of the taste characteristics, these products were less attractive with an increasing amount of flour in formula. The coefficients of the regression model were given as a result, it has helped to find out the patterns of influence of selected components and their dosage on the glycemic index, energy value and sensory characteristics of the product. The article represents the results, which can be used to create recipe compositions using selected ingredients.

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