How Sugar Fuels Cancer In The Body

Authored by Flora Zhao via The Epoch Times (emphasis ours),

You may have heard that sugar can feed cancer cells. Is that true?

This is supported by strong epidemiological evidence, he said.

A study published in PLoS One involving 1,011 colon cancer patients with a follow-up period of over seven years found that compared to patients consuming less than two servings of sugar-sweetened beverages per month, those who consumed two or more servings per day experienced a 67 percent increased risk of colon cancer recurrence or mortality.

Another Spanish study published in Clinical Nutrition in 2021 involving over 7,000 participants found that for every additional 5 grams of sugar consumed in liquid form per day, cancer incidence increased by 8 percent. People with the highest intake experienced a 46 percent increase.

A can of soda usually contains 30 to 45 grams of sugar.

A shift in a population’s sugar consumption can significantly affect cancer rates. Lewis Cantley, a well-known biologist and professor of cell biology at Harvard Medical School, used Taiwan as an example in an email to The Epoch Times. He wrote that before World War II, Taiwan had relatively low rates of cancers, including colon, endometrial, and breast. That was when sugar-sweetened beverages were scarce. Then, in the 1960s and 1970s, with the introduction of Western diets—particularly sugary drinks—cancer rates there steadily began to rise. They’ve now reached a level comparable to those in the United States.

Cancer cells require a substantial amount of glucose to survive. In the 1930s, Otto Warburg, a German biochemist, discovered that both cancer cells and normal cells require sugar, but their metabolic pathways differ: Normal cells primarily convert glucose into energy through aerobic respiration, while cancer cells obtain energy through glycolysis instead of using oxygen.

Cancer cells produce very little and inefficient energy due to their unique method of metabolizing sugar, which is why they voraciously consume sugar—at a rate 200 times faster than normal cells. That appetite can have wide-ranging effects.

The prevailing theory is that sugar doesn’t directly cause cancer but rather indirectly contributes to it through obesity.

High energy intake, or too many calories, and low energy expenditure are primary risk factors for many types of cancer, Ellen Kampman, a nutritional epidemiologist and chair in nutrition and disease at Wageningen University in the Netherlands, told The Epoch Times. A high sugar intake in the diet increases energy intake.

“Keeping a healthy weight is the most important thing you can do to prevent cancer,” she said.

A prospective study with over 35,000 participants revealed that people who consumed sugar-sweetened soft drinks more than once per day had an 18 percent increased risk of developing obesity-related cancers than those who rarely consumed such drinks.

A comprehensive review published in Cancers in 2023 indicated that about 48 percent of cancer cases are attributed to obesity. Obesity is linked to 13 types of cancer, including breast, colorectal, endometrial, liver, stomach, and thyroid.

A high-sugar diet can lead to the accumulation of body fat, especially visceral fat. Scientists recognize that the role of fat goes beyond energy storage; it acts as a highly active endocrine organ capable of secreting various substances, including hormones. Excessive fat can lead to an imbalance of these substances, contributing to cancer development.

“I certainly would not want my children to be in such a trial,” said Mr. Cantley, whose work has significantly impacted cancer cell biology.

Nevertheless, prospective cohort studies—a type of observational study focused on following a particular group of people over a period of time without interfering with their eating habits—can provide valuable insights into the relationship between sugar intake and cancer risk.

One such study, published in The American Journal of Clinical Nutrition in 2020, tracked over 100,000 French adults for several years. Those who consumed the most sugar had a 17 percent increased cancer risk compared to those with the lowest sugar intake. This elevated risk was particularly notable for breast cancer, with a 51 percent increase.

This association remained significant even after adjusting for factors such as weight gain and body mass index. The study suggested that sugar may increase cancer risk through mechanisms other than just weight gain.

High sugar intake can alter the metabolic profile, triggering inflammation and insulin resistance, both risk factors for tumor development.

This is a major mechanism that causes cancer, independently of obesity, he said. Obese people are more prone to inflammation and insulin resistance, but these can also occur in lean individuals.

Sucrose, fructose, and refined carbohydrates cause a significant spike in blood sugar levels. To maintain sugar balance, the body must increase insulin accordingly, and “excess amounts of increased insulin are inflammatory,” according to Mr. Cohen.

Thomas Seyfried, a professor of biology at Boston College, told The Epoch Times that high blood sugar is linked to systemic inflammation, which can lead to mitochondrial damage and, ultimately, cancer.