During the past couple of decades, following a diet that focuses on low-glycemic-index (GI) foods has become increasingly popular, especially in the treatment and prevention of diabetes. It’s so helpful for diabetes in particular because the glycemic index is a measure that helps assess the blood sugar-raising effects of various foods. The lower the GI, the less of an effect it will have on your blood sugar, which is the ultimate goal in treating diabetes.
People with diabetes also tend to have cardiovascular complications, which usually involve problems with cholesterol and high blood pressure. Many studies have been conducted on the effects of a low-GI diet and blood lipids (the main ones being HDL and LDL cholesterol and triglycerides), so researchers in London decided to analyze all of these studies to determine the consensus on low-GI diets and their effect on these blood lipids.
They examined 28 studies with the number of participants totaling 1,441. Analysis revealed that low-GI diets significantly reduced total cholesterol by 0.13 mmol/l and LDL (“bad”) cholesterol by 0.16 mmol/l, compared with higher-GI diets. No correlation was found between HDL (“good”) cholesterol and triglycerides and low-GI diets.
The reductions in LDL and total cholesterol appear to be greater in the studies with shorter duration time. Researchers suggest this is because participants’ compliance to the low-GI diet is better when the study isn’t as long.
Should You Go Low GI?
If you have diabetes or high cholesterol (or both), eating a low-GI diet is definitely the way to go. In fact, eating foods low on the glycemic index makes sense for everyone, even those who don’t have diabetes or heart or cholesterol problems.
To understand why, just look at a short list of foods that are high on the glycemic index scale:
- White bread and other white flour products
- Candy and other foods high in sugar
- Some very high-sugar fruits like watermelon
Basically, eating low-GI means eliminating unhealthy processed foods and white-flour products, as well as foods high in sugar, and instead focusing on filling your plate with lean protein, vegetables, whole grains, and certain fruits like berries.
For a good comprehensive list of the GI values of various foods, visit glycemicindex.com. Here, you can enter any food you want and find out its GI value. A higher number indicates a higher GI value. A value of 55 or over is considered high. White bread, for example, has a GI of 71. Raw carrots, on the other hand, have a GI of 35. Ideally, you want to keep the value of the foods you’re eating significantly below 55. Doing so can have a positive impact on your heart, cholesterol, weight and overall health.
 Goff LM et al. Low glycaemic index diet and blood lipids: a systemic review and meta-analysis of randomized controlled trials. Nutrition, Metabolism & Cardiovascular Disease. 2012. DOI: http://dx.doi.org/10.1016/j.numecd.2012.06.002.