Does Sugar Feed Cancer?

Wednesday, October 25, 2006 - 10:33am

By Erin Dummert RD, CD

If you search the Internet for sugar and cancer, you will find a barrage of warnings that sugar causes cancer. You might also be warned that since your doctor is not a nutritionist, he or she does not know the dangers of eating sugar, and is not providing you with the tools to prevent or fight the disease. For a cancer patient, this is extremely frightening information! Here is the truth about sugar and cancer from a registered dietitian and cancer nutrition specialist.

Sugar and hormones

It is true that sugar feeds cancer. But it is not as simple as some would have you believe. And it is certainly not as simple as curing cancer by cutting out all sugar. Sugar feeds every cell in the body, including cancer cells. The rest of the story is more complex, involving hormones such as insulin and insulin-like growth factor. The body releases these and other hormones that promote cell growth in response to a rise in blood sugar. These growth-promoting hormones are the real problem for people living with cancer.

Good sugars and bad sugars

Why does sugar take the rap when hormones are really the problem? Sugar does cause the body to release growth-promoting hormones, but that is not the whole story. Sugar is very important to life. However, just as there are good fats and bad fats, there are good sugars and bad sugars.

Bad sugars, often referred to as simple sugars, are those in foods that do not offer any other nutritional benefit. Examples of simple sugars include foods like soda, sweets, sugar cereals, juice drinks, and refined grains.

Good sugars, or complex carbohydrates, are present in foods that provide nutrients such as vitamins, minerals, protein, and fiber. Examples of complex carbohydrates include foods like fruit, vegetables, beans, and whole grains.

Reduce simple sugar intake

Simple sugars enter the bloodstream quickly and cause a rise in insulin and other growth-promoting hormones. Research shows that high levels of these hormones may increase the growth of cancer cells. The key to reducing these hormones is reducing your intake of simple sugars. Complex carbohydrates do not affect insulin the same as simple sugars, and thousands of research studies have shown that they actually reduce the risk of cancer.

Increase consumption of complex carbohydrates

By substituting complex carbohydrates for simple sugars in your diet, you can reduce your risk of cancer and other chronic diseases, such as heart disease and diabetes.

To reduce the amount of simple sugars in your diet make the following substitutions:

Instead of…


Orange juice

A whole orange

Strawberry flavored yogurt

Plain yogurt with fresh strawberries

White bread

Whole grain bread

White rice

Brown rice

Sugar cereal

Whole grain cereal

Fruit snacks

Fruit leather

Prepared salad dressing

Homemade vinegar and oil dressing