Sugar, Cancer and the Link


Cookies from the CancerCare Manitoba treat trolley

There are a few simple pleasures in life that we all take for granted. For example, a sweet treat like a cookie or a piece of pie can make us feel happy due to the sugar high (dopamine) we get when that sweet goodness hits our taste buds. Some people say sugar is much like an addictive drug.

However these sweet treats are not good for some of us. Especially if we indulge. Especially if we have an illness or condition that requires us to restrict the consumption of simple carbohydrates and too much sugar. For example, those who are diabetic are required to reduce the consumption of sweets and simple carbohydrates in order to keep their bodies running optimally.

One area that has caused a lot of debate is the consumption of sugar and how it relates to causing or feeding cancer. Some people believe that a diet including too much sugar causes cancer. Just do a Google search on “sugar feeds cancer” and you will find sensational articles such as this or this which don’t necessarily have all the correct information.  There have been many reliable scientific studies on this subject, and so far there is no conclusive evidence that eating more sugar leads to more cancer. However, according to the Canadian Cancer Society, we do know that being overweight or obese can cause an increased risk for developing cancer.

News agencies are always reporting on this topic, as people are desperately wanting to know how to prevent and treat cancer. CNN reported on “Sugar and cancer: Is there a link?” and it provides an overview of some of the research that has been done on the subject. The bottom line is that Thevelein, the researcher, does not believe that eating more sugar leads to more cancer. He goes on to say that eating a lot of sugar can cause one to become obese, and obesity is linked to a higher risk of cancer.

If anything, Thevelein suggests cancer patients eat less simple sugars and more complex sugars as those found in starch and whole grains. He recommends looking for alternative ways of providing sugar and energy to cancer patients rather than rapidly metabolized simple sugars.

My experience with cancer and sugar

This brings me to my own experience with cancer and my relationship to sugar. When I was diagnosed with anal cancer, my body and perhaps my mind, started to reject simple sugars. I avoided eating sweets, and I think my body was somehow rejecting the simple sugars. Intuitively my body and mind decided what my body needed was protein and complex sugars. I had read or heard over the years that sugar can cause cancer (true or not), so I guess this message was internalized.

I remember I used to love “Fibre One” bars. These are snack bars made with granola and chocolate chips. When I found out I had cancer, I couldn’t enjoy them anymore due to the extreme sweetness that I didn’t notice before. Other sweet treats I used to enjoy like chocolate were off my shopping list (for the time being).

To my surprise, as I was going through cancer treatment (chemotherapy and radiation), the volunteers would come around with cookies and drinks like coffee, tea and juice. It was a nice little treat to have while us cancer patients and sometimes our family or friends were with us. But it made me wonder, why, with all the fear of the link between sugar and cancer, would this be a refreshment of choice? I guess this was NOT an issue with the CancerCare Manitoba dieticians, doctors and other health care professionals. So at that point, I thought it must be okay to eat sweets like cookies during cancer treatment. Maybe everything I’d heard was hogwash.

Cancer risks include obesity and aging

As research progresses regarding the link between simple sugars and cancer, I will be curious to see what recommendations come out from leading cancer treatment centres. Will they still be serving cookies? Is this in the best interests of their patients? Are they encouraging the obesity epidemic, therefore increasing the risks for cancer? Perhaps there is a healthier alternative, such as some naturally sweet options or those made with natural sugars (i.e. fruit or applesauce)? For now, I will cut back on sugary sweets and have them in moderation.

“Getting older” is on the top of most lists regarding who is at risk for developing cancer. The American Cancer Society reports that nearly 9/10 cancers are diagnosed in people aged 50 and older. About half of men will be diagnosed and a third of women will be diagnosed with some form of cancer in their lifetime.

If you have cancer and you are concerned about your diet and how sugar affects your treatment and recovery, I would suggest you talk to a dietician who specializes in oncology. Your medical team can help direct you. If you don’t have cancer and you’d like to reduce your risk, please talk to your healthcare professional.

Be well.

Angela G. Gentile


Additional info:

University of Texas MD Anderson Cancer Centre (top-ranked cancer hospital in the USA in 2016) – Does sugar cause cancer?

Dana-Farber Cancer Institute – Does sugar feed cancer?

Mayo Clinic – Cancer causes: Popular myths about the causes of cancer

Oncology Nutrition – Sugar and Cancer


Angela G. Gentile  MSW, RSW is a clinical social worker and author of the book, “Caring for a Husband with Dementia: The Ultimate Survival Guide”, “A Book About Burnout: One Social Worker’s Tale of Survival” and the “Dementia Caregiver Solutions” app for iPhone and iPad. She lives in Winnipeg, Manitoba with her husband and has two adult children. She is creator of the Facebook communities – “Aging Well for Women” as well as “God, Cancer and Me.” For more information, visit: