The fact that sugar and obesity are linked to an increased risk of cancer is now becoming well-recognized. According to a report on the global cancer burden, published in 2014, obesity is responsible for an estimated 500,000 cancer cases worldwide each year.
How Excess Sugar and Obesity Promotes Cancer
One of the key mechanisms by which sugar promotes cancer and other chronic disease is through mitochondrial dysfunction.
Since sugar is not our ideal fuel, it burns dirty with far more reactive oxygen species than fat, which generates far more free radicals which in turn causes mitochondrial and nuclear DNA damage along with cell membrane and protein impairment.
Research6 has also shown that chronic overeating in general has a similar effect. Most people who overeat also tend to eat a lot of sugar-laden foods — a double-whammy in terms of cancer risk.
Chronic overeating places stress on the endoplasmic reticulum (ER), the membranous network found inside the mitochondria of your cells. When the ER receives more nutrients than it can process, it signals the cell to dampen the sensitivity of the insulin receptors on the surface of the cell.
Thus continuously eating more than your body really needs promotes insulin resistance by the mere fact that your cells are stressed by the work placed on them by the excess nutrients. Insulin resistance in turn is at the heart of most chronic disease, including cancer.
High-Fructose Corn Syrup Primary Culprit in CancerThis also helps explain why intermittent fasting (as well as other forms of calorie restriction) is so effective for reversing insulin resistance, reducing your risk of cancer, and increasing longevity.
Obesity, caused by a combination of eating too much refined fructose/sugar and rarely if ever fasting, may also promote cancer via other mechanisms, including chronic inflammation and elevated production of certain hormones, such as estrogen, which is associated with an increased risk for breast cancer.
According to recent research,7,8 from the University of Texas MD Anderson Cancer Center, refined sugar not only significantly increases your risk of breast cancer, it also raises your risk of tumors spreading to other organs.
Moreover, this study found that it was primarily the refined fructose in high-fructose corn syrup, found in most processed foods and beverages that was responsible for the breast tumors and the metastasis.
Without Sugar, Cancer Cannot Thrive
One of the most powerful strategies I know of to avoid and/or treat cancer is to starve the cancer cells by depriving them of their food source, which is primarily sugar and excessive protein.
Unlike all the other cells in your body, which can burn carbs or fat for fuel, cancer cells have lost that metabolic flexibility and can only thrive if there enough sugar present.
German cancer researcher Dr. Otto Warburg was actually given a Nobel Prize in 1931 for discovering this. Sadly very few experts have embraced his metabolic theory of cancer, but have embraced the nuclear genetic theory that is a downstream side effect of mitochondrial dysfunction.
Make no mistake about it, the FIRST thing you want to do if you want to avoid or treat cancer if you have insulin or leptin resistance (which 85 percent of people do) is to cut out all forms of sugar/fructose and grain carbs from your diet, in order to optimize the signaling pathways that contribute to malignant transformation.
Reduce Your Fructose and Non-Fiber Carb Intake
I recommend reducing your total fructose intake to a maximum of 25 grams/day, from all sources, including fruit. If you are insulin resistant, you’d do well to make your upper limit 15 grams/day.
Cancer patients would likely be best served by even stricter limits. For a more detailed discussion please review my interview with Professor Thomas Seyfried, who is one of the leading cancer pioneer researchers in promoting how to treat cancer nutritionally. I personally believe that most would benefit from reducing all non-fiber carbs (total carbs minus fiber), not just fructose, to less than 100 grams per day.
I typically keep mine around 50 to 60 grams every day.
The easiest way to dramatically cut down on your sugar and fructose consumption is to switch to REAL foods, as most of the added sugar you end up with comes from processed fare, not from adding a teaspoon of sugar to your tea or coffee. But there are other ways to cut down well. This includes:
- Cutting back on the amount of sugar you personally add to your food and drink
- Using stevia or luo han instead of sugar and/or artificial sweeteners. You can learn more about the best and worst of sugar substitutes in my previous article, “Sugar Substitutes — What’s Safe and What’s Not”
- Using fresh fruit in lieu of canned fruit or sugar for meals or recipes calling for a bit of sweetness
- Using spices instead of sugar to add flavor to your meal