The Science of...Fructose

Friday, May 17, 2013

Being the science nerd that I am, I’m becoming more interested in food chemistry and the science behind healthy living. I need to put that Biology degree to use, right?  

I thought it would be fun to do some research on areas of nutrition and health that seem to come up on a regular basis and make it a regular feature on my blog.  I'm game for anything! Plus, I have "Google-Syndrome" - if I don't know something, I look it up. A lot. To the point where it interferes with my everyday life.

The thing is, we hear a lot of conflicting information day in and day out.  One day the diet of choice is low carb-high protein and the next day it’s the total opposite.  There’s vegetarian, vegan, paleo, gluten-free, dairy-free, raw, etc.  How can we know what’s truly good for us?  

To keep it simple, I’m focusing on clean eating (I highly recommend Tosca Reno's The Eat-Clean Diet book).  I still eat some bread, cheese, meat, and even crap like candy and ice cream from time to time.  I’m starting small - making little changes here and there and focusing on eating clean, wholesome food that is as natural as I can get.  I can’t bring myself to eliminate whole food groups just yet but who knows...I'm might become a veggie one day.

There as so many buzz words in the world of dieting and weight loss.  One I’ve been hearing a lot lately is fructose.  So, what is fructose and what are it’s implications on our diet and our health?  

Fructose is a sugar found naturally in fruit and it is what we call a dietary monosaccharide, or a simple sugar like glucose and galactose.  Fructose is easily broken down in the body and it is almost exclusively metabolized in the liver, unlike glucose which is used for energy in all the cells of the body.  When we take in excess fructose, the body converts it to fat which usually ends up in the abdomen. 

I love fruit!  Especially berries with almonds in oatmeal.
Abdominal fat is much more dangerous than fat that is stored in our hips and thighs because it accumulates in and around our organs and causes a whole host of health problems including diabetes, obesity, fatty liver disease, and more. This is why the waist-to-hip ratio is often used to evaluate your risk for certain illnesses. There are many calculators online to tell you your waist-to-hip ratio.  Anything over 0.80 for women is considered worrisome.  

Fat accumulation on the organs is called visceral fat versus subcutaneous fat found beneath the skin (hello, cellulite!). One rule of thumb I've heard (not 100% if it's true) to tell what type of fat you have is the "Lay Down test."  Lay down on your back. If your fat drops to your sides and your stomach becomes flat, it is mostly subcutaneous.  If you still have a little pooch and your stomach sticks up, you most likely have visceral fat.  

Fructose isn't as much of a problem in the form of raw fruit. Raw fruit only contains a small amount and doesn’t impact the blood sugar level as dramatically as glucose. Adverse health effects are often observed when processed and concentrated forms of fructose are added to food and beverages - like the infamous high fructose corn syrup. Unfortunately this is where a large portion of Americans get their fructose intake - we didn’t get fat from eating fruit!

Lots of High Fructose Corn Syrup...this is why I no longer get Orange Leaf
So what’s the deal with high fructose corn syrup?  While there are still studies being conducted on this issue, it seems to boil down to too much of a good thing.  The fructose found in fruit is paired with fiber which may slow down the rate of absorption.  The concentrated nature of HFCS seems to have a shocking effect on the body and may impact the response and effectiveness of insulin.

For now, keep eating your favorite fruits (and veggies!).  The vitamins, minerals, and other valuable nutrients more than make up for the limited amount of fructose fruit contains.  The best thing to do is to limit or eliminate artificial sweeteners and say no to overly processed & concentrated HFCS containing products. Feel free to do more research - this is a simplified version!

A list of some common fruits and their fructose contents!


Please see the following links for more information:
General Information on Fructose:
General Information on HFCS:
The Issue Is Fructose,Period.
High-Fructose Corn Syrup Linked to Diabetes:


  1. The other HUGE problem with fructose (and other corn based foods) is the corn is GMO with PIP (Plant Incorporated Pesticide). I'm telling you... USA corn is scary! You can read all about it (in small print) on the FDA and EPA websites.

  2. You are totally right! I'm going to cover GMO when I read up more on gluten and wheat. I started reading Wheat Belly and it's truly eye opening!

    Doesn't it make you want to move to Europe where they are at least a little more cognizant of what's going into their food?