A study published in the American Journal of Clinical Nutrition, says that high carbohydrate diets my increase the risk of some types of breast cancer after the menopause.
Our body's need carbohydrates, they're a major source of energy; however, some are better for your than others. For example, many processed foods such as pasta, rice, white bread etc, have much of their fibre and nutrients removed, and what's left is mainly easily absorbed starch and sugar.
There are two different ways to measure the effect that carbohydrate foods have on our blood sugar levels:
The first is called the Glycaemic Index (GI). This measures how much food our raises blood sugar levels, on a scale of 1 to 100. The higher the GI number, the more that food will increase the level, and this in turn, increases the risk factor of many serious diseases, including heart disease and diabetes.
The second method is called the Glycaemic Load (GL). It includes the GI of the food, as also includes as the total amount of carbohydrate in the food as well.
The GL is generally considered to be more accurate in assessing the effect that different foods have on ourblood sugar and insulin levels.
High Glycaemic Load linked to an increase risk of breast cancer for some women.
The study was large and was conducted over 12 years. It examined the risk of breast cancer in 334,849 women aged between 34 to 66. The researchers evaluated the subjects diets in terms of GI, GL, and total carbohydrate intake.
During the course of the study 11,576 women were diagnosed with breast cancer. The researchers found that postmenopausal women with a high GL and high carbohydrate diet, had a significantly higher risk of breast cancer, when compared with the rest of the group.
There was no change in risk for women who had a high GL and high carbohydrate diet who were not postmenopausal.
Commenting on the findings, the study's authors said: “Our results also suggest a potential interaction between fibre intake and glycaemic load and carbohydrates on the risk of breast cancer,”
Healthy fats, and dietary fibre can both help slow down the absorption of carbohydrate into your system, and this will help lower the overall GL of your diet. So they key to this is eating the right foods, favouring those high in dietary fibre, that'll keep your blood sugar levels steady.
So, consider swapping everything that's white for everything that's brown! For example, brown bread, brown rice, and wholemeal pasta.
(Am J Clin Nutr 2012;96:345–55)