Does eating sugar really cause cancer?
You may have heard the statement, “sugar feeds cancer.” To date, research has not shown that sugar “feeds” cancer cells any more than sugar feeds all cells in our body. Cancer cells use glucose at a higher rate than normal cells because they are abnormal and divide at a much faster rate than normal cells. This is why cancer cells will light up on a PET scan and where the notion that “sugar feeds cancer” arises.
Every cell in the body needs glucose (simple sugar) for energy. Our bodies break down sugar and other carbohydrates (such as bread, cereal, pasta, fruit and starchy vegetables) into glucose. Even if you avoid all carbohydrates out of your diet, your body will make glucose for fuel from other sources such as protein and fat.
What we do know is that excessive intake of added sugar contributes to weight gain and obesity, which is a clear risk factor for many types of cancer. Excess body fat produces hormones which causes inflammation which can damage our cells. Cancer arises out of damaged cells. When we consume carbohydrates (sugar) our bodies produce insulin. Excessive intake of carbohydrates can cause chronically elevated insulin levels, increasing inflammation, and creating an environment that may promote growth of cancer.
Added sugars is any additional sugar that is not naturally occurring in a food item and is commonly found in processed and prepared food. How can we tell how much sugar is added in a processed food?
Look at the ingredient list to find added sugars. Look for the word “sugar,” which could also be listed as:
- Corn syrup
The 2015 Dietary Guidelines for Americans recommend limiting added sugar to 10% of your daily calories. That means, if you consume 2,000 calories per day, limit your added sugar intake to 10 teaspoons, which you could get in just one 12 ounce soda, leaving no room for any other added sugar items during the day. The American Heart Association has even stricter recommendations on sugar intake, because studies have shown that too much added sugar in your diet can significantly increase your risk of cardiovascular disease. They promote limiting added sugars to 9 teaspoons per day for men and 6 teaspoons per day for men.
It is important to note that naturally occurring sugars found in milk, yogurt, and fruits and are not considered “added sugars.” Fruits and other plant foods (whole grains, beans, vegetables) that our body breaks down into sugar contain fiber, vitamins, minerals and phytochemicals which play a role in preventing and fighting cancer.
So, the bottom line is that added sugar increases caloric intake without providing any of the nutrients that reduce cancer risk and eating too much of them contributes to obesity, which increases cancer risk. To reduce your cancer risk, it is wise to reduce your intake of added sugars and focus on including cancer protective plant foods such as beans, whole grains, whole fruits and vegetables as energy sources.