Can Fructose Cause Cancer? by Dana Carpender

This article first appeared just about exactly a year ago, on my blog:

Chances are you’ve seen the news already: Fructose can cause cancer. Specifically, this study looked at pancreatic cancer, a particularly deadly and intractable form of cancer, and one that has been increasing in frequency. I was unable to find the full text of this article, but gleaned that it demonstrated that cancer cells are particularly able to use fructose to reproduce, fueling tumor growth. Some thoughts:

• It was the first sentence in the abstract that really caught my eye: Carbohydrate metabolism via glycolysis and the tricarboxylic acid cycle is pivotal for cancer growth, and increased refined carbohydrate consumption adversely affects cancer survival. Got that? Carbohydrates are pivotal for cancer growth. Eating carbs means you’re less likely to survive cancer. Remember that next time someone tells you you’re courting cancer by eating meat and eggs instead of grains and fruit.

• Recently, with the backlash against high fructose corn syrup (HFCS), there’s been a flurry of products advertising that they’re made with “real cane sugar,” aka sucrose or table sugar. It is important to realize that sucrose is a disaccharide (double sugar molecule) made from one glucose and one fructose molecule. In other words, it’s half fructose.

• By comparison, the HFCS most commonly used in soft drinks is 55% fructose, only modestly higher in fructose than table sugar, with another version, used in foods, is 42% fructose, lower in fructose than table sugar.

• Honey is also a blend of glucose and fructose, containing about 38.5% fructose.

• Despite its current status as the Health Food Sweetener Du Jour, agave nectar is very high in fructose, with some coming in at 92% fructose or more.

• Whey Low, touted as a healthy sweetener useful for a low carb diet, lists “fruit sugar” as its first, and therefore most predominant, ingredient. “Fruit sugar” is fructose. Personally, I haven’t tried the stuff, and I don’t care to. I’m sure it has a fairly modest glycemic index, as does agave nectar; this is because fructose has a very mild GI. Doesn’t keep it from being bad for you.

• All of this suggests to me that when the abstract states that fructose consumption has increased dramatically over recent decades, it is pointing to a general increase in the consumption of sugar, roughly half of that being fructose. Much of this is, of course, in the form of beverages – not just soda, but juice, sports drinks, energy drinks and the like. Soda serving sizes have grown exponentially over the past couple of decades, but it’s not just soda intake that has increased. I know that, when I was a child, a “juice glass” held four fluid ounces. Most days that four ounces of orange juice was all the juice I drank; at lunch and dinner I drank milk. Now the “juice box” is ubiquitous, and many children never drink milk at meals. Likewise, I know many young people who down Gatorade by the liter, not because they’re participating in sports, but just because they like the sugary flavor, and perceive it as “healthier” than soda. It is not. Nor are juice drinks, or even most pure fruit juices. Apple juice has more sugar per ounce than Coca-Cola.

• The US government pushes five to seven servings of “fruits and vegetables” daily, as if fruits and vegetables were nutritionally equivalent. They are not. Fruit is a much richer source of fructose, and of sugars in general. Yet precisely because it is sweet, many health-conscious people load up on fruit to make up their five servings per day. If you’re eating strawberries or other low sugar fruits, this may be harmless. On the other hand, if you’re eating fruits richer in fructose, it may not. Eat your leafy greens.

• Similarly, there’s been a spate of juice blends that crow that they “hide a serving of vegetables” in a couple of servings of juice – in other words, they mix the not-so-sweet vegetable juices with the oh-so-sweet fruit juices, and sell it as a “solution” to the problem of not liking vegetables. It seems increasingly unlikely that this does a damned thing to improve your health.

• I find myself thinking of all of the poor, misguided people who, in response to a cancer diagnosis, decide to cut back on meat and fat and load up on fruit, or even, God forbid, fruit juice. A quick google on “cancer juice fast” turns up 324,000 pages. Frightening.

© 2011 by Dana Carpender. Used by permission of the author. What do you think? Please send Dana your comments to Dana Carpender.