Cancer Weight Gain and Weight Loss: What Might Be Causing It?

Cancer weight gain and weight loss are common side effects of the disease itself and of the therapies used to treat patients. For our purposes, we want to know whether the fact that cancer seems to predispose for overweight or underweight in some patients can tell us anything about the fundamental cause of obesity.

KEY POINT: Dietary carbohydrates appear to be able to cause cancer.

As we've discussed, two main hypotheses about what makes us fat have been put forward. Both find their origins in the law of energy conservation:

The Caloric Balance Hypothesis tells us that "excess calories" make us fat. "Calories In" and "Calories Out" are the key factors. Hence, overeating and under exercising cause cancer weight gain and exercising and calorie restriction cause cancer weight loss.

The Lipophilia Hypothesis reverses the causality and tells us that changes in our fat tissue cause either a negative or positive caloric balance. So cancer weight gain results from problems with hormones and metabolism.

Caloric Balance also tells us nothing about why "excess calories" might give us cancer or put us at greater risk for the disease.

Lipophilia, however, gives us a mechanism to test. It tells us that too many carbohydrates in the diet can cause both obesity (viz. disregulation of fat tissue) and cancer as well.

1. As Life Without Bread authors Christian B. Allan and Wolfgang Lutz note:

"too much insulin and glucose in the blood can cause cells to dedifferentiate, just as they do in cell lines, and thus can be a primary cause of dietary related cancer."[1]

The mechanisms by which insulin and glucose drive this dedifferentiation process are explained in chapter 10 of Life Without Bread ("Cancer: another disease of sugar metabolism?")

2. Alternatively, please see chapter 13 in Good Calories Bad Calories: "Dementia, Cancer, and Aging."[2]

Both of these discussions provide strong arguments and evidence that cancer and obesity are driven by the same underlying cause.

3. Articles online support these contentions as well. For instance, here's a paper written by a European physician entitled: "Can insulin cause cancer?"[3]

4. And here's an essay from US News and World Report entitled "The insulin connection: one hormone may cause cancer, heart attacks, and many more ills."[4]

5. Here's an article about cancer weight gain from Dr. Al Sears:

"Sugar feeds cancer cells and makes them grow like wildfire. Cancer loves sugar. And carbs turn into sugar in your body."[5]

Obviously exploring the possible etiologies of a disease as complicated and multifaceted as cancer is well beyond the scope of a single website. But there's a compelling case that cancer and obesity could be both caused by carbohydrate-induced hyperinsulinemia. This again would lend credibility to the Lipophilia Hypothesis and again discredit the Caloric Balance Hypothesis.

References