This study involved 67,000 post-menopausal women over 13 years and those in the obese category, with a BMI above 35 had a 58% increased risk of breast cancer. However, in this study the greater the BMI above 25, the greater was the risk. This increased risk related specifically to oestrogen positive cancers. Oestrogen, the hormone that encourages growth of hormonally sensitive tissue such as the womb and the breasts, is made in fat cells so adding the to oestrogen burden.
This link between weight and breast cancer is far from new. According to Dr Walter Willett of the Harvard School of Public Health “Being obese is associated with 14% of cancer deaths in men and 20% in women, compared with about 30% each for smoking.”
Other studies have shown that gaining weight in every decade from age 18 doubles risk of cancer.
All the evidence points to sugar metabolism being at the centre of the cancer process. By-products of sugar metabolism, called Advanced Glycation End-products (AGEs) lead to protein damage, aberrant cell signalling, increased stress responses, and decreased genetic integrity leading to normal cells switching over to cancer cells.
Far from breast cancer being ‘caused’ by genes it may be how a cell, and probably the energy factory called the mitochrondria within a cell, adapts and survives when sugar-damaged. Eating foods with a high GL is linked to a higher risk of breast cancer as well as other types of cancer including colorectal, pancreatic, ovarian, thyroid, endometrial and gastric cancer. Conversely, low-GL diets are associated with a reduced risk of breast, colorectal, ovarian, and endometrial cancers.
The more sugar you eat the more insulin is produced and postmenopausal women with high insulin levels have twice the risk of developing breast cancer. Diabetics also have increased cancer risk.
‘The primary function of insulin is viewed as a hormone that controls blood glucose level. However, there is growing evidence that aberrant insulin levels and insulin-mediated signalling can lead to cancer development and progression,’ say cancer researchers from India
A study from Italy reports that regularly eating sweet foods, including biscuits, ice cream, honey, and chocolate, may increase the risk of breast cancer. Results from a large case control study of more than 5000 Italian women have shown that the effects may be significant: “If real, the excess risk for frequent sweet consumption may account for 12% of breast cancer cases in this Italian population and, therefore, is far from negligible on a public health level,” say the researchers.
Also, as I discussed in my May newsletter (available to 100% Health Club Members) cancer is not ‘in the genes’ but a function of the environment of a cell, causing it to go into a survival mode. This Metabolic Theory of Cancer was first proposed by Dr Otto Warburg in the 1930s but is now right back in fashion as so few positive treatment results have occurred following the idea that cancer is primarily driven by mutant genes.
Very low sugar, low GL diets are proving highly effective in cancer treatment by, effectively, starving cancer cells of the only fuel they can burn – glucose.
We need to understand that cutting sugar, following a low GL diet and controlling weight are probably the most important positive actions you can take to reduce cancer risk, and especially breast cancer.