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Sugar and cancer: does sugar increase cancer risk?

woman looking into candy store

contributed by Nancy Burke, R.D., Danielle Karsies, M.S., R.D., and Melissa Shannon-Hagen, R.D., CSO, U-M Comprehensive Cancer Center Symptom Management and Supportive Care Program

You may have heard that sugar feeds cancer and to avoid all foods and beverages that contain sugar, but is this really necessary? Following such a restriction can significantly reduce your intake of foods that are rich in nutrients that have been shown to fight cancer such as fruits and whole grains. In addition, eating enough calories during cancer treatment can be difficult. Adding new, restrictive dietary changes can often lead to more stress which can also compromise your immune system. The following information is what the research shows in relation to sugar and cancer and how to incorporate healthy eating based on these findings.

Not all sugars are created equal

While most fruits do have a high sugar content, they are also rich in nutrients that are known to be cancer protective. Milk is another food that sometimes gets excluded due to its sugar content, but it too, is rich in important nutrients such as protein, which is in high demand during cancer treatment, and calcium. These nutrition powerhouses should not be grouped with other high sugar foods such as candy, cookies, and cakes. These sugar rich foods are high in sugar but low in healthy nutrients and should be eaten sparingly.

The sugar and cancer connection

According to the research, increased risk of cancer is not seen with sugar intake. Instead, cancer risk may be related to how your body responds to sugar. If you eat sugar rich foods all by themselves, especially if you are insulin-resistant, there is a greater spike in your blood sugars. This spikes results in an increased release of insulin-like growth factor (IGF), which has been shown to help cancer cells grow. If blood glucose levels are better controlled, less IGF is released which likely will decrease cancer growth.

Choose wisely

To avoid these spikes in your blood sugar, you don’t have to avoid all sugar containing foods; you just have to choose more wisely. If you eat protein, fat and fiber along with even the simplest sugars, these three items help the body make less insulin in response to simple sugar. For example, instead snacking on potato chips, choose a handful of nuts or have tortilla chips with low-fat bean dip. Try not to drink sugary beverages outside of meals or save dessert for later. Instead put both with healthy meals instead. Not only could you decrease your cancer risk, you could also decrease your risk of weight gain, by being satisfied with less dessert.

The Bottom Line

  • Limit simple sugars and refined grains. These include candy, cakes, cookies, pies, baked goods, white bread, refined pasta and white rice.
  • Reduce or eliminate intake of sugary beverages including fruit juice, soda pop and sports drinks.
  • Include naturally occurring sugar, such as the sugar that is found in fruit. The numerous vitamins, minerals, antioxidants, phytochemicals, and fiber they contain will do the body good.

Remember, eating healthy is not about excluding food. It’s about focusing on including more of the healthy foods such as whole grains, lean proteins, vegetables and fruits.

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