Fructose: A Hidden Nutritional Poison

November 02, 2005

Fructose: A Hidden Nutritional Poison 

 Competency #11 SUGAR and Fructose                              Reference:(New Reference: Am J Clin Nutr 2007 86: 899-906) 

 At my hospital, we are compiling a list of "Nutritional Competencies" for each of us to personally know.  It's not so long and hard to learn that list.  Learning to avoid Fructose is on that list.  We will give you the list when we have it finished.  It will be part of our guide to keep you informed. Strong Words!  What is fructose?  Isn't that a sugar from fruit?   Actually, pure fructose is from fruit, in its natural form.  Table sugar is a combination of two basic sugars, glucose and fructose.  We used to eat table sugar when we sweetened our food.  And we would get tiny amounts of fructose from fruit. 

Over the last 30 years, we have been gradually lured into eating more fructose.  Why?  It's more stable than sucrose, it's sweeter, it’s easier to transport, and it's cheaper to make.  Soda companies make 1-2 pennies a can (or bottle) off of each can they can switch from sucrose, table sugar, to fructose.   What's not to like? It's cheaper, more stable, easy to transport, is sweeter and everything a food company wants.   As long as YOU don't pay attention to the downsides. 

 The downside is on how your body functions with fructose instead of sucrose.  As we examine fructose, we first ask, how much is in our diet?  The answer, which caught my attention is that  9% of America's calories come from fructose (about 51 pounds per person per year)!  Most of this comes from sweetened drinks, but ketchup and many other prepared foods as well. 

 1.  Fructose can only be metabolized in your liver, where it makes a short cut into fat molecules.  Your liver cells get overloaded with fat.  Your blood triglycerides go up drastically (as much as 32% in one study).   Sucrose backs up and takes a while to be metabolized. 

 2.  Fructose modulates the insulin receptor in cells, making you put out more insulin to handle the glucose in your blood. 

 3.  VLDLs also go up in your blood.  They are part of the bad fats in your blood.


 4.  Fructose interacts with birth control pills to make a woman more insulin resistant. 

 5.  Fructose has been shown to cause a negative balance of micronutrients, mainly iron, magnesium, calcium, and zinc 

 6.  25 subjects with irritable bowel disease had increased mal-absorption with fructose. 

 7.   Studies with rats fed either high fructose or high glucose diets along with mild copper deficiency (a common American nutritional issue) showed marked collagen defects with cirrhosis and congestive heart failure killing the rats. 

 Basic Conclusion: Elevated blood fats are a high-risk component for heart disease, our number one killer.  There appears to be a virtual linear relationship between fructose consumption and our increasing obesity.  It messes up micronutrients to boot.  It is a bad choice. 

 WWW: What Works for Me.  I've stopped drinking sugared sodas AND sugared fruit drinks and teas.  You should too.  Corn sweetener is the code word you should look for on processed foods.  If you want to be a sensible shopper, you ought to think about all sweetened drinks.   Pure fruit juice is fine.  You can handle the small amount of fructose in part because when you eat that much fruit or juice, you are getting all the other micronutrients, vitamins and fiber.

This column was written by Dr. John E. Whitcomb, Brookfield Longevity, Brookfield, WI. (262-784-5300)