No proof that sugar directly causes cancer, as claim suggests

There are many misconceptions about sugar consumption and cancer causes, as well as how the two relate to one another. One common myth found on social media is that sugar causes cancer.

"It’s been proven that sugar triggers and causes cancer," said Dr. Eric Berg in a 30-second video on Facebook. Berg, who describes himself as an expert on the keto diet and intermittent fasting, went on to say that sugar "in large amounts over a period of time" causes cancer.

"And the other thing that’s interesting about this is that cancer has an avid, greedy hunger for sugar. It will compete for normal cells for its glucose. So the best thing to do to prevent cancer is to avoid sugar," said Berg, who was a previously practicing chiropractor, but is no longer licensed.

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Additional research is needed to explore the relationship between sugar in a person’s diet and cancer, according to the Mayo Clinic. To date, studies have not found a direct link between sugar and cancer. However, there is some evidence that consuming large amounts of sugar can put a person at a higher risk of certain cancers.

Eating a lot of sugary foods, such as cookies, cakes and soda, can lead to weight gain and excess body fat. Being overweight or obese can increase a person’s risk for 11 different cancers, including colorectal, postmenopausal breast, ovarian and pancreatic cancer.

However, that doesn’t mean it’s necessary to completely avoid consuming sugar, the Dana-Farber Cancer Institute said.

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Simple sugar, known as glucose, is the body’s main source of energy. All cells, including cancer cells, use glucose as their fuel. Glucose can come from any food with carbohydrates, including healthy foods and foods with added sugars.

"The idea that sugar, or glucose, could fuel the growth of cancer cells can lead some people to unnecessarily avoid all carbohydrate-containing foods. This approach assumes that if cancer cells need glucose, then cutting it out of one’s diet will stop cancer from growing," the Dana-Farber Cancer Institute said.

But it’s not that simple. Since all cells need glucose to function and grow, there is no way for the body to only give glucose to healthy cells, rather than cancerous ones.

In fact, health experts warn that not consuming enough carbohydrates can lead to muscle loss and malnutrition. This can also make it more difficult for a person to undergo cancer treatment and recovery.

"It’s been proven that sugar triggers and causes cancer," a video on Facebook said. "So the best thing to do to prevent cancer is to avoid sugar."

Although consuming large amounts of sugar can put a person at higher risk of certain cancers, sugar itself is not carcinogenic. Avoiding sugar altogether will not stop cancer from growing and doing so could also lead to unhealthy weight loss.

We rate this claim Mostly False.