Why is Fructose so Deadly?

by Graham Simpson, M.D.

By now, I am sure you do not need me to tell you that sugar is bad for your health.

This particular piece of information has been relatively common knowledge for many years, not to mention the subject of several public health campaigns in almost every corner of the globe. What you may not know, however, is that not all sugar is created equal.

In fact, some sugars are much worse for us than others. And it may be surprising to hear that a kind of sugar that occurs naturally in fruit might just be the worst of them all.fructose


Now, before you throw all your apples and mangoes in the bin, let’s look at some facts. In the traditional Western diet, we do indeed encounter fructose in fruit. And while it’s important not to eat fruit to excess (more on that later), there are other ways this deadly sugar sneaks into our diet – namely in the form of high-fructose corn syrup (HFCS).

While the name may not sound familiar, your body already knows all about it. HFCS is an artificial sweetener that is used by the food industry because it is cheaper and sweeter than sugar. It can be found in everything from soft drinks, breakfast cereal, fruit juice and flavoured milk through to salad dressing, sauces, soups, bread and candy. And the list goes on and on.

In fact, perhaps the only thing as worrying as the long list of foods that contain HFCS is the longer list of diseases which research is increasingly showing to be linked to the sweetener. So let’s take a deeper look at these different types of sugar, where they are found in our diet, and the impact they are having on our health.

Understanding the different types of sugar

There are three key sugars we regularly encounter in our day-to-day diet: Sucrose, glucose and fructose. The primary difference between the three is in how our bodies process them.

Sucrose is what we know as table sugar and is obtained from both sugar cane and sugar beet. The building blocks of sucrose are fructose and glucose. When sucrose is consumed, these two compounds are broken down at different rates. Glucose is the body’s preferred source of energy and is either instantly converted or stored within the muscle cells for later use.

If excess energy from the fructose is not immediately required then it is poured into fat synthesis. What’s more, as fructose can only be broken down by liver cells, it leaves in its wake a number of fatty deposits which not only harm the liver but also cause damage much further afield. We’ll go into that in a moment.

While fructose will always take a toll on the liver, there are certainly ways to limit the impact – mostly in how we consume it. For example, our bodies better tolerate fructose in the presence of glucose. Therefore, foods that contain at least as much of one as the other (such as bananas, grapefruit) will do less harm than those that are high in fructose alone, such as carbonated drinks. It does have to be said that even fruits that have a high fructose-to-glucose ratio at least contain many healthy vitamins and nutrients. This absolutely cannot be said of the majority of foods that contain HFCS which is a perfect storm of poor health: Sugar that the body struggles to break down, accompanied by low-mineral content.

The liver, the heart and the consequences of fructose

However you get your fructose intake, ingest it regularly and in too high a quantity and the effect on your health can be devastating. So long is the list of potentially harmful conditions linked to the sweet stuff that I feel I should break this next part down into bite-size chunks to make it easy to digest (something fructose most certainly isn’t).

As the only organ able to break the substance down, our poor livers bear the brunt of the damage caused by fructose. One of the many harmful by-products of this metabolism are fat droplets which accrue within the liver and are thought to contribute to a condition known as non-alcoholic fatty liver disease (NAFLD) – so called because it closely mimics the effect of alcohol on this most vital of organs.

As with alcohol damage, if left untreated the liver becomes scarred, leading to irreversible cirrhosis and irreparable damage. Though many are still unfamiliar with NAFLD, it is one of the most common diseases in the US, affecting up to 90 million people. A study published in the Digestive and Liver Disease journal supported the association of NAFLD with metabolic syndrome – abnormalities that precede the development of both type 2 diabetes and cardiovascular disease.

There’s more bad news for the liver too. As well as fatty deposits, fructose metabolism leaves behind several other nasty by-products: Triglycerides, uric acid and free radicals. The first of these, triglycerides, not only clogs up the liver and impairs its function but when released into the bloodstream contributes to the build-up of plaque on artery walls. Meanwhile, uric acid has a part to play in this process too, by turning off the production of nitric oxide – a substance that helps to protect those very same artery walls. Finally, free radicals are known to damage cell structures, enzymes and genes.

Now, I mentioned cardiovascular disease and I want to return to that point. It’s bad news there as well – as if you hadn’t guessed. The 2011 Harvard Heart Letter suggests that due to the way the body breaks down fructose it is not just negatively impacting the liver but the heart as well. As fructose goes through the liver it increases bad cholesterol, promotes fat around organs, and heightens blood pressure – all of which harms arteries and the heart. The publication also cited two other studies which had made the link between high fructose intake with heart disease.

Fructose and diabetes

We talk a lot about diabetes. Why? It’s one of the UAE’s most common medical conditions, with one in five people in our country thought to have the condition. And I believe that half the world’s population now suffers from diabetes or prediabetes due to insulin resistance caused by excess sugar.

While many in the medical profession have stopped short of pointing the finger for the diabetes epidemic at the door of fructose, the evidence – particularly when it comes to HFCS – is pretty damning. According to a 2012 study published in Global Public Health, cases of type 2 diabetes are 20% higher in countries with a higher availability of HFCS.

There is more research to be done specifically on fructose in this area, but the jury is in on the damage the general sugar-overloaded Western diet is doing. So this in itself should be an immediate warning not only against foods packed with sugars but also grains and processed foods. If you keep as a general rule the minimisation of sugar, you can’t go too far wrong.

Fructose and obesity

In the UAE, our obesity rate is double the global average. Fructose, and in particular HFCS, is surely a contributing factor to that. As we have already covered, fructose can only be processed in the liver – as opposed to glucose which can be converted into energy by practically every cell in our body. Much of the fructose is turned into fatty acids, cholesterol and triglycerides, all of which get stored as fat. And the more we overwhelm our liver, the less it can cope and the more fat is produced as a result.

Fructose also plays a big part in weight gain and obesity through the way it interacts with leptin – a hormone which tells the brain when we have adequate fat stores and no longer need to keep eating. While glucose stifles our appetite by stimulating leptin and suppressing the hunger hormone, fructose has no effect on this whatsoever and blocks the transport of leptin from the blood to the brain. Therefore, the brain incorrectly believes that we need to eat more and burn less to replenish our fat stores.

And just remember here that obesity has taken more lives than all previous epidemics combined, but because it kills over decades rather than days or weeks it is not something that is commonly recognised as being a life or death condition.

Don’t fall foul of fructose

In the end, the conditions mentioned above are really just the big hitters. The section on diseases connected to fructose could fill an article all by itself.

So after reeling off a rap sheet as long as that, what is really left to say about this potentially deadly substance? Well, I should start by making clear that excessive consumption of fructose, by any means, is not good for you. And it is in the form of HFCS where it is taking the heaviest toll – largely down to the sheer amount of the stuff we consume.

To give you an idea of just how abundant this harmful substance is in our diets, we only need to look at the huge increase in sugar consumption over the years. Now in the early 1900s, the average American took in around 15 grams of fructose – mostly from natural sources such as fruit or vegetables. Fast forward to today and the average American is putting away in excess of 55 grams of fructose a day (almost entirely due to the amount of HFCS in the modern Western diet – a diet that we are more than familiar with here in the UAE). And in the UK stats tell us that in 1700 sugar consumption was about 4-5 pounds per person per year, and today sits at 155 pounds.

Needless to say, something else has risen dramatically in that time too – rates of lifestyle diseases such as type 2 diabetes and obesity. As for NAFLD, it has gone from being practically non-existent 100 years ago to affecting around one-third of Americans in the modern day.

Now, we also need to keep an eye on the amount of fructose we are getting from natural sources as well. So those apples, cherries and grapes while undoubtedly good for us do need to be taken in moderation just like anything else in our diet.

But as always, if you want to make a good first step, start by looking through your cupboards. Because some of the most dangerous things we are exposed to in our daily lives are in those shiny packets and tins (processed foods) that we eat from every day.

Graham-150x150About Dr. Simpson

Graham Simpson, M.D. is the Chief Medical Officer of West-Martin Longevity. He is also the Founder & Medical Director of the innovative Intelligent Health Center, Dubai, UAE.

Dr. Simpson graduated from the University of Witwatersrand Medical School in Johannesburg, South Africa and is Board Certified in Internal Medicine, Emergency Medicine, and Age Management Medicine (A4M). He is a founding member of the American Holistic Medical Association (AHMA) and is a licensed homeopath. Dr. Simpson has also taught as an assistant professor of medicine at the University of Nevada, Reno.

He is the author of WellMan (Live Longer by Controlling Inflammation); co-author of Spa Medicine with Dr. Stephen Sinatra; and the forthcoming Reversing CardioMetabolic Disease.

Dr. Simpson was the Founder of PrimalMD; the Founder of the Eternity Medicine Institute; Paleo4me; and the Inflamaging Physician Network. He is a Consultant to Cenegenics, Inc

He has practiced I.N.T.E.G.R.A.L. Health for many years and remains committed to delivering Proactive Health to physicians and clients around the world.

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