Clinical question
How effective are low glycaemic index (GI) diets on total mortality, cardiovascular (CV) events, and CV risk factors (blood lipids, blood pressure) in healthy people or people who have established CV disease or related risk factors?
Bottom line
There was no evidence available regarding the effect of low GI diets on CV disease events. Moreover, there was no convincing evidence that low GI diets had a clear beneficial effect on blood lipids or blood pressure parameters. Minimum study duration was 12 weeks.
Caveat
None of the studies reported on mortality (total or CV) or CV events. Most of the studies did not have intervention durations of longer than 6 months. It should be noted that the GI of the low and high GI diets was measured in most of the studies by food diaries and showed considerable variation.
Context
The GI is a measure of the ability of a carbohydrate (for example sugar or starch) to affect blood sugar levels. Interest is growing in this area for the clinical management of people at risk of, or with, established CV disease.
Cochrane Systematic Review
Clar C et al. Low glycaemic index diets for the prevention of cardiovascular disease. Cochrane Reviews, 2017, Issue 7. Art. No.: CD004467.DOI: 10.1002/14651858. CD004467.pub3. This review contains 21 studies involving 2538 participants.
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