Why Is Fructose Bad For You?

Written by Dr. Steve Chaney on . Posted in Fructose

Is It The Sugar, Or Is It The Food?

Author: Dr. Stephen Chaney

 

why fructose bad for youI don’t usually report on studies done in mice, but this study sheds light on a particularly puzzling question: Why is fructose bad for you?

The studies are clear-cut. High fructose consumption is associated with inflammation, obesity, non-alcoholic liver disease, insulin resistance, type 2 diabetes, kidney disease, increased LDL cholesterol and triglycerides, and heart disease. Based on these associations, fructose appears to be deadly. Why would anyone want to consume it?

Yet fructose is found in virtually every fruit. In fact, fructose, also known as fruit sugar, was first isolated from fruits. Hence the name fructose. Humans have been eating fruits safely for thousands of years. Fruits are very good for us. That raises the question: “If fruits are good for us, how can fructose be bad for us?”.

An important clue can be found by looking at what the food industry has done to the American diet. Because fructose imparts a pleasurable, sweet taste to foods, the food industry keeps adding it to more and more foods. As a result, dietary intake of fructose has increased 100-fold over the past two centuries. It has reached the point where fructose now accounts for almost 10% of the caloric intake in the United States.

 

Is It The Sugar, Or Is It The Food?

 

Let me expand the discussion by using a couple of graphics I developed for my book, “Slaying The Food Myths.”  

There Are No Sugar Villains. There Are No Sugar Heroes:

why fructose bad for you sugar foodVirtually all sweeteners are primarily a mixture of fructose and glucose. The graphic on the left compares high fructose corn syrup (the current villain) with other “natural” sweeteners used in foods (our current heroes). High fructose corn syrup ranges from about 40% fructose to 55% fructose. The exact percentage depends on what kind of food product is being made with it. Honey and coconut sugar are about 45% fructose. Sucrose and grape juice concentrate are around 50% fructose. Apple juice concentrate is around 60% fructose, and agave sugar comes in at a whopping 80% fructose.

In other words, if fructose is the culprit that everyone makes it out to be, “healthy” sugars are no better than high fructose corn syrup. Simply substituting a “healthy” sugar for high fructose corn syrup is unlikely to provide any meaningful benefit.

 

Is It The Sugar, Or Is The Food?

why fructose bad for you fruitsThis graphic shows us what a nutrition label would look like on a medium apple. I am sure that label is a wake-up call for many of you. The amount of sugar and the percentage of fructose and glucose are about the same as in an 8-ounce soda sweetened with high fructose corn syrup. The same is true for virtually every other fruit you can think of.

Now let me share one more thing you won’t hear from what I refer to as “Dr. Strangelove’s Health Blog” (You probably know the ones I am referring to). Virtually all the studies showing the bad effects of fructose consumption have been done with sodas and sugary junk foods. They haven’t been done with apples.

In fact, virtually every study looking at fruit and vegetable consumption has shown they are incredibly good for us. They lower inflammation and reduce the risk of obesity, diabetes, heart disease, and cancer. And, the more the better. One study found that the health benefits of fruit and vegetable consumption topped out at around 10 servings a day.

With this background, you should now fully understand why the question “If fruits are good for us, how can fructose be bad for us?” is so perplexing.

My simplistic explanation has always been that whole foods like fruits have fiber, which slows the absorption of fructose from the intestine. Our bodies were designed to handle fructose in a safe manner when it enters the bloodstream slowly. Sodas and junk foods, on the other hand, have little to slow the absorption of fructose. When fructose enters the bloodstream rapidly, our “safe” metabolic pathways for handling it are overwhelmed, and it is forced into the pathways that are harmful. For example, the “excess” fructose is converted to fat by the liver, which causes inflammation, obesity, fatty liver disease, and triglyceride production.

This is, of course, simply my hypothesis for explaining the different effect of fructose in fruits and sodas. It is based on sound metabolic principles, but it is far from proven. That is why I found the current study (C. Jang et al, Cell Metabolism, 27: 351-361, 2018 ) so interesting. It provides a metabolic rationale for my hypothesis.

How Was The Study Done?

Mice were fed a 1:1 mixture of fructose and glucose at doses that approximated the ranges of typical human fructose consumption. The fructose was isotopically labeled so that fructose and its metabolites could be identified by LC-MS (liquid chromatography – mass spectrometry). After feeding the mice the labeled fructose, the investigator measured the amount of fructose and its metabolites in various organs and in the portal vein, which transports sugars from the intestine to the liver for additional metabolism before they enter the bloodstream.

 

Why Is Fructose Bad For You?

why fructose bad for you intestine liverThe first surprise was that most of the fructose was metabolized by the intestinal mucosal cells that line the small intestine rather than the liver. Previous reports had assumed that fructose was primarily metabolized by the liver because that was where most of the bad effects of fructose metabolism had been observed.

These investigators observed that fructose was primarily converted to glucose and small molecular weight metabolites by the intestinal mucosal cells before being released into the portal vein, where they were transported to the liver. However, there was a strong dose response effect.

  • At low fructose doses, 90% of fructose was metabolized by intestinal mucosal cells before being released to the liver.
  • At high fructose doses, only 70% of fructose was metabolized by intestinal mucosal cells.
  • That means at high fructose doses the amount of fructose reaching the liver unchanged increases from 10% to 30%. That is a 3-fold increase!

The authors concluded:

  • “Based on these findings, we propose that the small intestine shields the liver from fructose and that excessive doses of fructose overwhelm the small intestine, spilling over to the liver where they cause toxicity.”
  • “A key difference between the health effects of fiber-rich fruits (and perhaps even fiber-rich prepared foods) and juices/sodas is their rate of intestinal fructose release.”
  • “It is likely that the appearance rate of free fructose in the small intestine plays a critical role in dictating its metabolic fate. Like the lower doses in our experiments, a slower rate of fructose appearance will result in more complete intestinal clearance, whereas higher doses and faster rates result in fructose overflow to the liver.”

This study needs to be confirmed, and the mechanism may be entirely different in humans. However, whether the mechanism is the same in mice and humans is immaterial. We already know that fructose in sodas and junk foods exerts a very different effect on our health than fructose in fruits and other fiber-containing foods.

The Bottom Line

 

Previous studies have clearly shown that fructose in sodas and junk foods is bad for us, while fructose in fruits is good for us. A recent study in mice provides a metabolic explanation for this difference. The study found:

  • At low fructose doses, 90% of fructose was metabolized by intestinal mucosal cells before being released to the liver.
  • At high fructose doses, only 70% of fructose was metabolized by intestinal mucosal cells.
  • That means at high fructose doses the amount of fructose reaching the liver unchanged increases from 10% to 30%. That is a 3-fold increase!

The authors concluded:

  • “Based on these findings, we propose that the small intestine shields the liver from fructose and that excessive doses of fructose overwhelm the small intestine, spilling over to the liver where they cause toxicity.”
  • “A key difference between the health effects of fiber-rich fruits (and perhaps even fiber-rich prepared foods) and juices/sodas is their rate of intestinal fructose release.”
  • “It is likely that the appearance rate of free fructose in the small intestine plays a critical role in dictating its metabolic fate. Like the lower doses in our experiments, a slower rate of fructose appearance will result in more complete intestinal clearance, whereas higher doses and faster rates result in fructose overflow to the liver.”

This study needs to be confirmed, and the mechanism may be entirely different in humans. However, whether the mechanism is the same in mice and humans is immaterial. We already know that fructose in sodas and junk foods exerts a very different effect on our health than fructose in fruits and other fiber-containing foods.

For more details, read the article above.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

 

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Latest Article

Headache Relief By Treating Your Shoulder

Posted June 18, 2019 by Dr. Steve Chaney

A Headache Remedy Can be Treating Your Shoulder

Author: Julie Donnelly, LMT –The Pain Relief Expert

Editor: Dr. Steve Chaney

 

 

When you experience the debilitating effects of headache pain, you just want headache relief.

headache relief from painYour head throbs. It’s hard to think. It’s hard to enjoy life.

What should you do?

  • You could take Tylenol or some other drug, but that offers temporary relief at best.
  • You could see a chiropractor, but it may take multiple visits to correct your problem.
  • You could get a massage, but the headache will probably come back.

What you really want is a natural protocol you can use to make the headache go away whenever it occurs. There is such a protocol. It’s called muscular therapy, and I teach people how to perform it on themselves whenever a headache or joint pain occurs.

 

What Is The Difference Between Massage And Muscular Therapy?

There is a difference between massage and muscular therapy as a headache remedy, and both are worthwhile.  Massage is great for moving the fluids (like blood and lymph) through your body and getting muscles to relax. It’s perfect if you’re under stress and you feel like you’re going to explode.  A good massage therapist can have a positive impact on your nervous system and blood pressure, and you’ll come out walking on air.

Muscular therapy, the way I do it anyway, is more focused than it is general.  You’ve heard about spasms, but most people can’t visualize a spasm, so they ignore the term. You probably have an idea that a spasm may be painful, and it isn’t a great thing to have, but what is a spasm?

What is a Spasm

headache relief muscle knotsI explain it as a knot in the muscle.  Through some very complicated physiology (that none of us need to know about) the muscle forms a knot in the thick part of the muscle, and it’s putting a strain on the two ends.

Both ends are attached to a bone, so the pressure causes a strain on the end points and you have pain at the bone.  Most of the time the end points are just after the muscle crosses over a joint, so you end up with joint pain.

 

Too often people think this is arthritis and they are stuck suffering or taking strong drugs to mask the pain.  But in the majority of cases it’s not arthritis, it’s just tight muscles pulling on the bones of the joint and preventing them from moving freely.

But, all you need is to know where the knot (spasm) is, and then apply direct pressure on it.  Hold the pressure for 30 seconds or so, and then let go.  Keep repeating this until it doesn’t hurt anymore.

Headache Relief

headache relief shoulderLet’s say you have headache pain.  There are so many muscles that impact headaches that it would take a book (like my book: “Treat Yourself to Pain-Free Living”) to discuss each of them.  So, let’s just look at one muscle, the Levator Scapulae.

The Levator Scapulae is responsible for lifting your shoulder up.  In fact, the nickname for the Levator Scapulae is “the shrug muscle.” But look at this graphic and you’ll see where the knots form (the round red circles) and where you feel the pain (the red shaded areas).

You may not think to press on your lower neck/shoulder when you feel headache pain.  This muscle also causes the pain you feel in the middle of your back, between your shoulder blades.

 

And self-treatment is so easy!

 

headache relief shoulder muscle workYou can put your opposite thumb into the front of your shoulder as shown in this picture, and your fingers in the back of the muscle. Then squeeze your thumb and fingers so they pinch the entire muscle.

 

headache relief shoulder muscle pressure using wallOr you can put the perfect ball on the very top of your shoulder and then lean into the corner of a wall as shown in this picture.

 

What you are doing is forcing the acid (as in Lactic Acid) out of the muscle fiber so blood can fill the void and heal the muscle fiber.  As you do this you are untying the knot and the pressure is removed from the joint. In most cases the joint can now move more freely and without pain.

All the self-treatments in my book are just this easy!

Most people have significant pain relief, and I am happy to say many get total and permanent pain relief.  Try it yourself, self-treatment is easy.  The worst thing that can happen is nothing, and the best thing that can happen is regaining normalcy.

Why stay in pain when it’s so easy to find the muscular source of the problem and eliminate it?

pain free living book coverGet Treat Yourself to Pain-Free Living . It is filled with over 100 pictures and descriptions proven to show you how to find and self-treat muscle spasms from head to foot!

Join the 1000’s of people worldwide who have discovered that tight muscles were the true source of pains they thought were from arthritis, fibromyalgia, and other serious conditions.  You have nothing to lose, and everything to gain by releasing tight muscles.

Treat Yourself to Pain-Free Living is your step-by-step guide to pain relief!

 

Wishing you well,

 

Julie Donnelly

Julie Donnelly

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

 

About The Author

Julie Donnelly is a Deep Muscle Massage Therapist with 20 years of experience specializing in the treatment of chronic joint pain and sports injuries. She has worked extensively with elite athletes and patients who have been unsuccessful at finding relief through the more conventional therapies.

She has been widely published, both on – and off – line, in magazines, newsletters, and newspapers around the country. She is also often chosen to speak at national conventions, medical schools, and health facilities nationwide.

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