The fact that sugar and obesity are linked to an increased risk of cancer is now becoming well-recognized. Obesity has also been linked to an increased risk of death from all causes.
According to research published in 2013, nearly 1 in 5 U.S. deaths is associated with obesity.1 More recently, researchers published findings from a meta analysis of 239 studies covering four continents, saying excess body weight is responsible for 1 in 5 of all premature deaths in the U.S. and 1 in 7 in Europe.2,3,4
On average, carrying excess weight may reduce your life expectancy by about one year, while being moderately obese may result in a three-year reduction in lifespan. Those of normal weight had the longest life expectancy and the lowest risk of dying before the age of 70.
Considering facts such as these, it’s no surprise that the financial burden of excessive sugar consumption is also great.
According to the Credit Suisse Research Institute’s 2013 study5 “Sugar: Consumption at a Crossroads,” as much as 40 percent of U.S. healthcare expenditures are for diseases directly related to the overconsumption of sugar, and this includes obesity, diabetes and cancer.
So, sugary processed foods may be cheap on the front end, but they exact a hefty price tag down the line.
Diet Can Influence Your Cancer Risk in More Ways Than One
Your diet plays a crucial role when it comes to obesity and related health problems such as elevated blood sugar, insulin resistance and cancer. Research suggests obesity can promote cancer via a number of different mechanisms.
One of the key mechanisms by which sugar promotes cancer and other chronic disease is by causing mitochondrial dysfunction. Sugar is not an ideal fuel for your body as it burns “dirty,” creating far more reactive oxygen species (ROS) than fat does when it’s metabolized.
As a result, excessive amounts of free radicals are generated when you eat excessive sugar, which in turn causes mitochondrial and nuclear DNA damage, along with cell membrane and protein impairment.
So, contrary to conventional teaching, nuclear genetic defects do not cause cancer. Rather, mitochondrial damage happens first, and this then triggers nuclear genetic mutations.
Research6 has shown that chronic overeating in general has a similar effect, as it 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 additional work placed on them by the excess nutrients. Insulin resistance in turn is at the heart of most chronic disease, including cancer.
Sugar Is a Key Contributor to Cancer
Most people who overeat also tend to eat many sugar-laden foods, which promotes elevated blood sugar levels and insulin resistance. So overeating sugary foods equates to a double-whammy in terms of cancer risk, compared to overeating whole, unprocessed fare.
In fact, recent research has identified sugar as the top contributor to the worldwide cancer surge. According to a report7 on the global cancer burden, published in 2014, obesity is responsible for an estimated 500,000 cancer cases worldwide each year.
The reason for this is because cancer cells are primarily fueled by the burning of sugar anaerobically. Without sugar, most cancer cells simply lack the metabolic flexibility to survive.
Normal, healthy cells have the metabolic flexibility to adapt from using glucose to using ketone bodies from dietary fats. Most cancer cells lack this ability so when you reduce net carbs (total carbs minus fiber), you effectively starve the cancer. This is why nutritional ketosis appears to be so effective against cancer.
According to recent research 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.8
It was primarily the refined fructose in high-fructose corn syrup (HFCS) found in most processed foods and beverages that was responsible for the breast tumors and the metastasis.
The Role of Genetics, Proteins and Hormones
While genetic defects are not a primary cause of cancer, genes can still play a role. Scientists have discovered that a number of genes known to promote cancer by influencing cell division — including a gene called AKT — also regulate cells’ consumption of nutrients.
So certain genes actually appear to play a role in cancer cells’ overconsumption of sugar. Whereas healthy cells have a feedback mechanism that makes it conserve resources when there’s a lack of food, cancer cells do not have this mechanism and feed continuously.
These proteins (VEGF, PAI-1 and PEDF) promote angiogenesis, a process your body uses to build blood vessels that tumors need to thrive. The greater the women’s weight loss, the greater their reduction in these proteins.
Previous research suggests losing weight can reduce your risk of breast, colon and prostate cancer by as much as 20 percent, and this effect is thought to be due to reductions in these proteins and other inflammatory compounds stored in fat cells.10
Obesity also triggers overproduction of certain hormones, such as estrogen, which is associated with an increased risk for breast cancer.
Links Between Diabetes and Cancer Are Getting Stronger
Overall, insulin resistance is one of the key contributors to a heightened cancer risk, and many studies have confirmed that type 2 diabetics are at greater risk.
One recent study, which included more than 1 million adult cancer patients, found that those diagnosed with type 2 diabetes were 23 percent more likely to have received a cancer diagnosis during the decade preceding their diabetes diagnosis compared to non-diabetics.11,12
Recent research has also noted that a growing number of obese Americans have poor blood sugar control, which in turn promotes rising rates of type 2 diabetes and associated health conditions. To combat this trend, the researchers urge overweight people to consider “serious weight loss efforts.”
Ketogenic Diet May Be Key to Cancer Recovery
Nutritional ketosis is part of the answer here. In this type of diet, you replace net carbs (total carbs minus fiber) with moderate amounts of high-quality protein and high amounts of beneficial fat. Since cancer cells need glucose to thrive, and carbohydrates devoid of fiber turn into glucose in your body, cutting out net carbs quite literally starves the cancer cells. Additionally, low protein intake tends to minimize the mTOR pathway, which also helps restrict cell proliferation.
The video above features Thomas Seyfried, Ph.D., who discusses how, as a metabolic disorder involving the dysregulation of respiration, malignant cancer (in this case brain cancer) can be managed by altering your metabolic environment.
That said, this kind of diet (low in net carbs, moderate in high-quality protein and high in healthy fats) will also help normalize your weight and boost your general health for the simple reason that it helps you convert from carb burning mode to fat burning, which helps optimize your mitochondrial function.
What to Eat for Optimal Health and Cancer Prevention
From my perspective, ignoring diet as a cancer prevention tool is foolhardy at best. I’m convinced most cancers are preventable through proper nutrition. Avoiding toxic exposures (such as pesticides) is another important factor, and this is one reason why I recommend eating organic foods, especially grass-fed or pastured meats and animal products, whenever possible.
•Healthy fats, 75 to 85 percent of your total calories. Beneficial monosaturated and saturated fats include olives and olive oil, coconuts and coconut oil, butter made from raw grass-fed organic milk, raw nuts such as macadamia and pecans, seeds like black sesame, black cumin, pumpkin and hemp seeds, avocados, grass-fed meats, lard and tallow, ghee (clarified butter), raw cacao butter, organic pastured egg yolks, animal-based omega-3 fats and small fatty fish like sardines and anchovies.
•Carbohydrates, 8 to 15 percent of your daily calories. Aim for twice as many fiber carbs as non-fiber (net) carbs. This means if your total carbs is 10 percent of your daily calories, at least half of that should be fiber. Fiber has a number of other health benefits, including weight management and a lower risk for certain cancers.23
Cancer patients would likely be best served by even stricter limits. By reducing the amount of net carbs you eat, you will accomplish four things that will result in lowered inflammation and reduced stimulation of cancer growth. You will:
•Lower your serum glucose level
•Reduce your mTOR level
•Reduce your insulin level
•Lower insulin growth factor-1 (IGF-1, a potent hormone that acts on your pituitary gland to induce metabolic and endocrine effects, including cell growth and replication. Elevated IGF-1 levels are associated with breast and other cancers).
Excellent sources of high-fiber carbs that you can eat plenty of include chia seeds, berries, raw nuts, cauliflower, root vegetables and tubers such as onions and sweet potatoes, green beans, peas, broccoli, Brussels sprouts and psyllium seed husk.
•Protein, 7 to 10 percent of your total calories. Quality is important, so look for high-quality grass-fed or pastured meats and animal products. As a general rule, I recommend limiting your protein to 0.5 g of protein per pound of lean body mass, which for most people amounts to 40 to 70 g of protein a day.
Again, the reason for limiting protein is because excessive amounts have a stimulating effect on the mTOR pathway, which plays an important role in many diseases, including cancer. When you reduce protein to what your body needs for cell repair and maintenance, mTOR remains inhibited, which helps minimize your chances of cancer growth.