Scientists have proved for the first
time that fructose, a cheap form of sugar used in thousands of food
products and soft drinks, can damage human metabolism and is fueling
the obesity crisis.
Fructose, a sweetener usually derived
from corn, can cause dangerous growths of fat cells around vital organs
and is able to trigger the early stages of diabetes and heart disease.
Over 10 weeks, 16 volunteers on a controlled
diet including high levels of fructose produced new fat cells around
their heart, liver and other digestive organs. They also showed signs
of food-processing abnormalities linked to diabetes and heart disease.
Another group of volunteers on the same diet, but with glucose sugar
replacing fructose, did not have these problems.
This study takes its place in a growing lineup of scientific studies
demonstrating that consuming high-fructose corn syrup is the fastest
way to trash your health. It is now known without a doubt that sugar
in your food, in all it’s myriad of forms, is taking a devastating
toll.
And fructose in any form -- including
high-fructose corn syrup (HFCS) and crystalline fructose -- is the worst
of the worst!
Cardiovascular disease, liver disease,
cancer, arthritis and even gout
A Calorie is Not a Calorie
Glucose is the form of energy you were designed
to run on. Every cell in your body, every bacterium -- and in fact,
every living thing on the Earth--uses glucose for energy.
If you received your
fructose only from vegetables and fruits (where it originates) as most
people did a century ago, you’d consume about 15 grams per day
-- a far cry from the 73 grams per day the typical adolescent
gets from sweetened drinks. In vegetables and fruits, it’s mixed
in with fiber, vitamins, minerals, enzymes, and beneficial phytonutrients,
all which moderate any negative metabolic effects.
It isn’t that fructose itself is
bad -- it is the MASSIVE DOSES you’re exposed to that make it
dangerous.
There are two reasons fructose is so
damaging:
Your body metabolizes fructose in a much
different way than glucose. The entire burden of metabolizing fructose
falls on your liver.
People are consuming fructose in enormous
quantities, which has made the negative effects much more profound.
Food and beverage manufacturers began
switching their sweeteners from sucrose (table sugar) to corn syrup
in the 1970s when they discovered that HFCS was not only far cheaper
to make, it’s also about 20 times sweeter than table sugar.
This switch drastically altered the average
American diet.
By USDA estimates, about one-quarter
of the calories consumed by the average American is in the form of added
sugars, and most of that is HFCS. The average Westerner consumes a staggering
142
pounds a year of sugar! And the very products most people rely on
to lose weight -- the low-fat
diet foods -- are often the ones highest in fructose.
Making matters worse, all of the fiber
has been removed from these processed foods, so there is essentially
no nutritive value at all.
Fructose Metabolism Basics
Without getting into the very complex
biochemistry of carbohydrate metabolism, it is important to understand
some differences about how your body handles glucose versus fructose.
I will be publishing a major article about this in the next couple of
months, which will get much more into the details, but for our purpose
here, I will just summarize the main points.
Dr. Robert Lustig[i] Professor of Pediatrics
in the Division of Endocrinology at the University of California, San
Francisco, has been a pioneer in decoding sugar metabolism. His work
has highlighted some major differences in how different sugars are broken
down and used:
After eating fructose, 100 percent of
the metabolic burden rests on your liver. But with glucose, your liver
has to break down only 20 percent.
Every cell in your body, including your
brain, utilizes glucose. Therefore, much of it is “burned up”
immediately after you consume it. By contrast, fructose is turned into
free fatty acids (FFAs), VLDL (the damaging form of cholesterol), and
triglycerides, which get stored as fat.
The fatty acids created during fructose
metabolism accumulate as fat droplets in your liver and skeletal muscle
tissues, causing insulin resistance and non-alcoholic fatty liver disease
(NAFLD). Insulin resistance progresses to metabolic syndrome and type
II diabetes.
Fructose is the most lipophilic carbohydrate.
In other words, fructose converts to activated glycerol (g-3-p), which
is directly used to turn FFAs into triglycerides. The more g-3-p you
have, the more fat you store. Glucose does not do this.
When you eat 120 calories of glucose,
less than one calorie is stored as fat. 120 calories of fructose results
in 40 calories being stored as fat. Consuming
fructose is essentially consuming fat!
The metabolism of fructose by your liver
creates a long list of waste products and toxins, including a large
amount of uric acid, which drives up blood pressure and causes gout.
Glucose suppresses the hunger hormone
ghrelin and stimulates leptin, which suppresses your appetite. Fructose
has no effect on ghrelin and interferes with your brain’s communication
with leptin, resulting in overeating.
If anyone tries to tell you “sugar
is sugar,” they are way behind the times. As you can see, there
are major differences in how your body processes each one.
The bottom line is: fructose leads to
increased belly fat, insulin resistance and metabolic syndrome -- not
to mention the long list of chronic diseases that directly result.
Of course, many things are “natural”
-- cocaine is natural, but you wouldn’t want to use 142 pounds
of it each year.
The food and beverage industry doesn’t
want you to realize how truly pervasive HFCS is in your diet -- not
just from soft drinks and juices, but also in salad dressings and condiments
and virtually every processed food. The introduction of HFCS into the
Western diet in 1975 has been a multi-billion
dollar boon for the corn industry.
The FDA classifies fructose as GRAS:
Generally Regarded As Safe. Which pretty much means nothing and is based
on nothing.
There is plenty of data showing that
fructose is not safe -- but the effects on the nation’s health
have not been immediate. That is why we are just now realizing the effects
of the last three decades of nutritional misinformation.
As if the negative metabolic effects
are not enough, there are other issues with fructose that disprove its
safety:
More than one study has detected unsafe
mercury levels in HFCS[ii].
Crystalline
fructose (a super-potent form of fructose the food and beverage
industry is now using) may contain arsenic, lead, chloride and heavy
metals.
Nearly all corn syrup is made from genetically
modified corn, which comes with its own set of risks.
The FDA isn’t going to touch sugar,
so it’s up to you to be proactive about your own dietary choices.
What’s a Sugarholic to Do?
Ideally, I recommend that you avoid as
much sugar as possible. This is especially important if you are overweight
or have diabetes, high cholesterol, or high blood pressure.
I also realize we don’t live in
a perfect world, and following rigid dietary guidelines is not always
practical or even possible.
If you want to use a sweetener occasionally,
this is what I recommend:
Avoid ALL artificial
sweeteners, which can damage your health even more quickly than
fructose.
Avoid agave
syrup since it is a highly processed sap that is almost all fructose.
Your blood sugar will spike just as it would if you were consuming regular
sugar or HFCS. Agave’s meteoric rise in popularity is due to a
great marketing campaign, but any health benefits present in the original
agave plant are processed out.
Avoid so-called energy
drinks and sports drinks because they are loaded with sugar, sodium
and chemical additives. Rehydrating with pure, fresh water is a better
choice.
If you or your child is involved in athletics,
I recommend you read my article Energy
Rules for some great tips on how to optimize your child’s
energy levels and physical performance through good nutrition.
[i] Robert H. Lustig, MD: UCSF
Faculty Bio Page, and YouTube presentation “Sugar:
The bitter truth” and “The fructose epidemic”
The Bariatrician, 2009, Volume 24, No. 1, page 10)
