Many people have heard the statement that “sugar feeds cancer”. I
have had patients whose friends, family or other source told them to
completely avoid sugar. I’ve even heard some well-intentioned, but somewhat misguided health professionals tell this to patients!
This series of posts will hopefully set the
record straight regarding what we know about sugar and cancer.
Our bodies need sugar, specifically glucose, for energy. Every cell
of our body, especially the brain, needs glucose to live. The sugar that
we need comes from 2 places. One is from the carbohydrate that we eat.
When we eat carbohydrates (either complex carbs, like whole grains or simple carbs like syrups), our body digests them and breaks them down into glucose for the body to use.
The second source of glucose is actually from our body. Our body will make the sugar we need if we
don’t get enough from our food.
Therefore, even if you cut out all intake of sugar or other form of
carbohydrate, your body will make the sugar you need from fat and
protein. This is not the ideal situation for your body, as it can cause
your body to go into a stressful state. There is a certain amount of
carbohydrate that is important for healthy cell function.
Cancer cells use sugar for energy just like the rest of our body. Cancer does have a higher metabolism than other cancer cells, which is why it takes up sugar at a faster rate and therefore causes the “glow” or “light up” on a PET scan. But
there’s nothing about the cancer that “feeds” on sugar more than any
other cell in our body.
At this point, it has not been shown that eliminating dietary sources of sugar and carbohydrate actually results in slower growth of tumors. It does result in your body having to work extra hard to make the glucose that it needs to function.
Sugar and Insulin
When we digest and absorb sugar from different types of foods, our
bodies produce insulin to process the sugar. This is a normal and
essential part of metabolizing food. However, if you eat too much sugar
or carbohydrate, it results in a large amount of insulin being produced.
Insulin tells our cells to grow. Too much insulin can tell our cells
to grow too much. Some people think that too much insulin could cause
cancer cells to grow more. There’s not enough research right now to
fully understand how insulin and cancer are related, but we know that
too much sugar, and too much insulin is not good for our health.
Simply put, sugar does feed cancer. BUT, sugar (glucose) also feeds the rest of your body.
For those who are going through treatment, remember that your healthy
cells need energy especially during this time. Avoiding sugar completely
will not help treatment, but it could leave your healthy cells low on
My next post will address the various sources of sugar and
how you can make the healthiest choices when it comes to your risk for
disease. More from me later!