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Avoid the Hidden Dangers of High Fructose Corn Syrup

Why and how to keep this sweetener out of your diet

health hazards of corn syrup

High fructose corn syrup has crept into more of our foods over the last few decades. Compared with regular sugar, it’s cheaper and sweeter, and is more quickly absorbed into your body. But eating too much high fructose corn syrup can lead to insulin resistance, obesity, Type 2 diabetes and high blood pressure.


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Functional medicine expert Mark Hyman, MD, explains the many ill effects of high fructose corn syrup, and offers strategies to avoid it.

Fat production factory for your body

Fructose was initially thought to be a better choice for people with diabetes due to its low glycemic index. But only your liver cells can process fructose, and that’s where the problems begin.

“Fructose goes straight to your liver and starts a fat production factory,” Dr. Hyman says. “It triggers the production of triglycerides and cholesterol.” He explains that it’s actually the sugar — not the fat — that causes the most trouble for your cholesterol.

What’s even worse, Dr. Hyman notes, is high doses of fructose “punch little holes in your intestinal lining, causing what we call a leaky gut.” He explains that this allows foreign food proteins and bacterial proteins to enter into your bloodstream, which triggers inflammation, makes you gain weight and causes Type 2 diabetes.

Increases appetite, promotes obesity

Studies show that high fructose corn syrup increases your appetite and promotes obesity more than regular sugar. “High fructose corn syrup also contributes to diabetes, inflammation, high triglycerides and something we call non-alcoholic fatty liver disease,” says Dr. Hyman, adding that it increases all the fat in the liver, which now affects over 90 million Americans.

“It can even cause fibrosis or what we call cirrhosis. In fact, sugar in our diet is now the major cause of liver failure and that makes sugar the leading cause of liver transplants,” he continues.

Alternative options

So, should you stay away from everything fructose?

Well, you should as much as possible, says Dr. Hyman, but fruit is the exception.

Fruit has fructose, but it’s naturally occurring and it doesn’t have the same effects as high fructose corn syrup. Additionally, fruit is packaged with fiber, vitamins, minerals and all sorts of healing nutrients. So, unless you eat massive amounts of fruit, fructose shouldn’t be a problem.

High-fructose corn syrup represents more than 40% of the caloric sweeteners that are added to our foods and beverages. If you find the words “high-fructose corn syrup” or the new term “corn sugar” on a label, stay away if you want to be healthy. “These are signs of very poor quality foods,” states Dr. Hyman. He adds that the easiest way to completely avoid high-fructose corn syrup is to eat real, whole, unprocessed foods.


But if you must buy packaged foods, he advises reading the labels carefully to identify sugar in other disguises.

“Sugar is hidden in over 80% of the 600,000 processed foods on the market,” he says. But beware: It’s disguised with over 200 different names — things like maltodextrin and other additives you wouldn’t necessarily recognize.

As a general rule of thumb. Dr. Hyman advises, “If you can’t pronounce it, or you don’t recognize the ingredients, or you wouldn’t add it to food you cooked in your own kitchen, then don’t eat it!”


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