Low glycemic diet does not improve risk factors for cardiovascular disease and diabetes

December, 2014

A trial in which 163 overweight adults with elevated blood pressure were given one of four complete diets that contained all their food for five weeks has found that a low glycemic diet did not improve insulin sensitivity, lipid levels or blood pressure. But it's important to note than all diets were based on a healthful DASH-type diet, varying only in their glycemic index and carbohydrate proportions.

So, the trial found that a healthy diet with low–glycemic index carbohydrate-containing foods didn't improve insulin sensitivity, HDL cholesterol levels, LDL cholesterol levels, or systolic blood pressure any more than the healthy diet with high–glycemic index foods It did reduce plasma triglyceride levels slightly more.

In fact, the low–glycemic index with high-carbohydrate diet was worse than the high–glycemic index, high-carbohydrate diet — decreasing insulin sensitivity and increasing LDL cholesterol and LDL apolipoprotein B levels. This finding was unexpected and inconsistent with other research. However, a meta-analysis of 28 trials found that lowering glycemic index did not affect HDL cholesterol or triglyceride levels and lowered LDL cholesterol level only if fiber content was also increased.

In line with the researchers' previous findings, the DASH diet had slightly better effects when its carbohydrate content was reduced. When the same calories were instead supplied by unsaturated fat and protein, triglycerides and VLDL levels were substantially lowered and diastolic blood pressure slightly lowered.

As in previous trials, all the DASH-type diets lowered blood pressure and LDL cholesterol levels.

Previous research has shown inconsistent results on whether low glycemic index helped people lose weight.

http://www.eurekalert.org/pub_releases/2014-12/bawh-lgd121614.php

Sacks FM, Carey VJ, Anderson CM, et al. Effects of High vs Low Glycemic Index of Dietary Carbohydrate on Cardiovascular Disease Risk Factors and Insulin Sensitivity: The OmniCarb Randomized Clinical Trial. JAMA. 2014;312(23):2531-2541. doi:10.1001/jama.2014.16658.

Goff  LM, Cowland  DE, Hooper  L, Frost  GS.  Low glycaemic index diets and blood lipids: a systematic review and meta-analysis of randomised controlled trials. Nutr Metab Cardiovasc Dis. 2013;23(1):1-10.

Related News

Data from 196,383 older adults (60+; mean age 64) in the UK Biobank found that a healthy lifestyle was associated with lower dementia risk regardless of genes.

Both an unhealthy lifestyle and high genetic risk were associated with higher dementia risk.

A diet containing compounds found in green tea and carrots reversed Alzheimer's-like symptoms in mice genetically programmed to develop the disease.

A study involving 116 healthy older adults (65-75) has found that higher levels of several key nutrients in the blood were associated with more efficient brain connectivity and better cognitive performance.

A long-running study involving 8225 adults found that self-reported diet during midlife (mean age 50) was not significantly associated with subsequent risk for dementia.

Dietary choline linked to reduced dementia risk & better cognition

A mouse study has found that canola oil in the diet was associated with worsened memory, worsened learning ability, and weight gain in Alzheimer's mice.

A Finnish study involving over 1000 older adults suggests that a counselling program can prevent cognitive decline even among those with the Alzheimer’s gene.

A pilot study involving 106 participants of the Rush Memory and Aging Project who had experienced a stroke followed participants for an average of 5.9 years, testing their cognitive function and monitoring their eating habits using food journals.

A small study involving 50 younger adults (18-35; average age 24) has found that those with a higher BMI performed significantly worse on a computerised memory test called the “Treasure Hunt Task”.

Another study adds to the growing evidence that a Mediterranean diet is good for the aging brain.

Pages

Subscribe to Latest newsSubscribe to Latest newsSubscribe to Latest health newsSubscribe to Latest news