The Truth about High Fructose Corn Syrup

High fructose corn syrup is a corn product, but there’s nothing really natural about it. It’s been enzymatically processed in a different way from normal digestion, so that the simple sugar glucose changes into fructose. That makes it a lot sweeter than you’d expect corn to be.

How sweet is high fructose corn syrup?

Well, it depends. There isn’t just one formula for high fructose corn syrup. It’s a whole range of different formulas. Some of them are even sweeter than basic table sugar.

Two other things make high fructose corn syrup taste even sweeter than it really is. First, the sweet taste of fructose hits faster than the sweet taste of glucose or sucrose. That makes you think you’re tasting more sweetness.

Second, fructose which is mixed with glucose or sucrose makes the whole thing taste sweeter than any of these separately. That’s why table sugar these days is mixed with fructose, but it doesn’t have as much fructose as high fructose corn syrup.

Glucose and fructose in nature

Glucose is a really common natural sugar. Everything that contains sugar naturally contains mostly glucose sugar. Every cell in your body can metabolize glucose directly.

Fructose is a lot less common in nature. There’s a bit of it in cane sugar, but you’ll find it most in fruits, which used to be uncommon enough in nature that they became special desserts rather than the main meal.

Your body doesn’t naturally encounter large amounts of fructose, so only your liver can metabolize it.

But it’s still just sugar, right?

The problem with high fructose corn syrup is that it has a lot of fructose compared to glucose. 

It’s true, you’re not going to gain weight from eating sugar, any kind of sugar, if you don’t eat a lot of sugar. It’s also easier for your blood sugar to stay in a normal range if you don’t eat a lot of sugar.

However, when you eat glucose, your body secretes insulin to digest it. It reduces the amount of circulating ghrelin, so you don’t feel hungry anymore. And it lowers the activity of the hypothalamus, so you start to feel full.

Fructose acts weirdly on the body and brain compared with glucose. Your body produces less insulin than with glucose. It doesn’t really reduce the amount of circulating ghrelin, so you still feel hungry. And it actually spikes activity in the hypothalamus, so you don’t feel full at all.

All of that, plus the sweet sweet taste, means that when you’re eating too much fructose, your body isn’t telling you when you’ve had enough, and your taste buds and hypothalamus want you to have even more. You’re supposed to want less of it because it’s so sweet, but your body’s craving more. That’s a perfect recipe for overeating.

Corn syrup and corn subsidies

High fructose corn syrup’s a corn product. America has to import a lot of its sugar, but it produces a lot of corn. High tariffs on sugar keep the prices of imported sugar high, and high corn subsidies to corn producers keep the prices of American corn low.

That’s why high fructose corn syrup’s a lot more common in America than just about anywhere else in the world. Things which are made with sugar elsewhere are made with high fructose corn syrup in the United States. It’s just cheaper for the business owner, and it’s pretty good for the corn farmer too.

But it’s not cheaper for the taxpayer who pays for those subsidies! And it’s also not cheaper for your household. Because of those tariffs, plain old sugar in the US costs twice what it does in other developed countries!