High sugar content in western diet increases risk of breast cancer tumours and metastasis

The high sugar content in a typical western diet has a significant impact on the development of breast cancer and metastasis (spread of cancer from one organ to another) to the lungs, according to a new study conducted by researchers from the University of Texas. Although the negative effects of sugar on health have been covered by various studies, this is the first time the direct effect of sugar consumption on the development of breast cancer has been linked, said the study.

The report focuses on the effects of sugar on 12-lipoxygenase (12-LOX), an enzyme catalyst, during chemical reactions and its impact on mammary gland tumour development in mice. The study found that mice that were fed western diets with high sugar content had increased tumour growth and metastasis, when compared to mice that were fed a non-sugar starch diet. This was because of an increased expression of 12-LOX and a related fatty acid called 12-HETE.

"We determined from our experiments that specifically fructose, in table sugar and high-fructose corn syrup, ubiquitous within our food system, is responsible for facilitating lung metastasis and 12-HETE production in breast tumours," said co-author of the study Lorenzo Cohen, professor of Palliative, Rehabilitation, and Integrative Medicine.

Further, in the lab mice fed with high sugar western diets, excessive fructose resulted in damage to brain synaptic activity. When the animals turned six months old, 30% of mice on a starch-control diet had measurable tumours, whereas 50 to 58% of the mice on sucrose-enriched diets had developed mammary tumours. This second batch of mice also developed resistance to insulin, a vital hormone that keeps your blood sugar level from getting too high.

High sugar consumption has often been cited as the main villain behind the epidemic of obesity, heart disease, diabetes and cancer worldwide. With this study indicating even more negative effects of sugar on health, researchers say moderate sugar consumption is critical to avoid any of these health hazards.