High fructose corn syrup: Stop vilifying HFCS and start limiting sugar of all types

candy bar — When it comes to your health, it's more about how much sugar you eat, not necessarily what type.
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High fructose corn syrup has a reputation for contributing to the growing obesity epidemic, but recent data indicate that excess sugar in all forms is to blame, not just HFCS.
A major risk related to a diet high in excess sugar is insulin resistance, which can lead to type 2 diabetes.
While diabetes, liver disease, and cancer may be related to fructose consumption specifically, all added sugars, including high fructose corn syrup, should be consumed in moderation.
This article was medically reviewed by Samantha Cassetty, MS, RD, nutrition and wellness expert with a private practice based in New York City.
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According to the FDA, there is no evidence that foods with high-fructose corn syrup are less safe than foods containing similar amounts of other types of sugar.

The concern is the amount of sugar you are eating, not what kind of sugar, says Kyle Fagnanon, MS, RDN, a registered dietician and founder of Strata Nutrition.

The negative health effects of consuming too much added sugar are well known, but whether HFCS poses additional risks is debatable.

Find out more about the health concerns connected to high fructose corn syrup.

High Fructose Corn Syrup and Obesity

A widely cited 2004 study launched the notion that HFCS was a key culprit in the US obesity epidemic. However, more recent data has suggested otherwise.

According to a 2009 review, the use of HFCS peaked in 1999 and has since dropped, while the obesity rates have remained high.

Although the research is mixed, "the thing that seems consistent is that added sugars of all types should be limited," says Fagnanon.

That's where HFCS can be more of an issue than natural sugar, because it's less expensive to produce and, therefore, is a common additive in many popular foods including soda, juice, and candy, as well as less obvious foods like tomato sauce and salad dressing.

And, in fact, chemically-speaking, HFCS and table sugar are similar:

Table sugar is molecules of fructose and glucose bound together in a one-to-one ratio, forming sucrose.
HFCS is a mix of unbound fructose and glucose molecules, made from combining water and cornstarch. HFCS is sweeter than table sugar but both are considered added sugars since they aren't naturally present in foods.

Health concerns

Eating a lot of sugar, of any kind, comes with multiple health risks:

Nutritional deficiency: Sugar heavy foods tend not to be the most nutritious, so you are likely missing out on important vitamins and minerals.
Weight gain: Foods with added sugars are frequently high in calories, which can lead to weight gain. Foods with naturally occurring sugars, like fruit, tend to be lower in calories.
Dental trouble: And, of course, sugar is bad for your teeth and can cause decay and cavities.
Heart disease: Excessive sugar increases levels of triglycerides, a type of fat, which can put you at risk for heart disease. Fructose in particular can lead to hypertension because it increases uric acid, which raises blood sugar.

That's not all the havoc that excess added sugars like HFCS can wreak.

Diabetes

One major risk from a diet high in fructose is insulin resistance, which can lead to type 2 diabetes.

A 2009 study looked at the effects of consuming fructose vs. glucose in overweight patients between the ages of 40 and 72. For 10 weeks, participants drank a sweetened beverage — either with glucose or fructose — alongside their regular diet.

At the end of the 10 weeks, the researchers found that insulin sensitivity did not change in the group consuming glucose-sweetened drinks, but decreased 17% in the group consuming fructose-sweetened drinks. Decreased insulin sensitivity can lead to insulin resistance, a factor of type 2 diabetes.

Non-alcoholic fatty liver disease

Fructose can take a toll on your liver.

Fructose is metabolized in your liver, and consuming too much fructose — in the form of HFCS or another added sugar— can overwork it making it harder for your liver to function properly.

And that's important since your liver is responsible for converting toxins in your blood into waste products and producing bile to break down fats, says Fagnanon.

But how much fructose is too much? A 2008 study compared patients with non-alcoholic fatty liver disease to a control group and found the NAFLD group consumed two to three times more fructose (365 calories/day) than the control group (170 calories/day).

Cancer

Fructose consumption may also put you at risk for certain types of cancer, including pancreatic cancer and small intestine cancer, according to a 2012 review.

Research also shows that fructose may indirectly increase tumor growth by enhancing protein synthesis, and it is associated with more aggressive cancer behavior, including metastasis, or the spread of cancer.

Glyphosate

Because HFCS is made from corn, there is concern about contamination with glyphosate, an herbicide, says Fagnanon. Glyphosate is toxic to human cells, according to a 2020 review, but epidemiological studies looking at the effect of glyphosate exposure on individuals are contradictory.

In 2015, the World Health Organization's cancer agency, International Agency for Research on Cancer (IARC), labeled glyphosate as "probably carcinogenic" for consumers, but risk assessment is ongoing. Although glyphosate is used on corn crops, that doesn't mean it is always present in corn syrup.

Takeaways

High-fructose corn syrup is often seen as a "red flag" on ingredient labels due to its reported connection to heart disease, diabetes, liver disease, and certain types of cancer.

While high-fructose corn syrup has some serious health risks, it's important to remember that just because HFCS gets a lot of attention, it's not the only sugar that is cause for concern, says Fagnanon.

All sources of added sugar should be limited to the daily recommended intake level, as one type of sugar isn't necessarily better for you than another.

Many of the health risks associated with HFCS are linked to consuming high amounts of added sugar, in general. Some health risks, such as diabetes, liver disease, and cancer, may be related to fructose consumption specifically. As with any added sugar, HFCS should be consumed in moderation.