For years, high-fructose corn syrup (HFCA) has been the controversial bad boy in the world of processed foods and beverages. Some authorities say avoid it at all costs. Others say it’s OK in moderation but there is no across-the-board agreement as to how much is moderation and how much is risking one’s health. Medical authorities don’t always agree with each other on what’s a safe amount of HFCA to consume and the food industry has its own guidelines for consumption. Is there any wonder consumers are confused?

A team of doctors at the Mayo Clinic has published a statement on the dangers of HFCS consumption and called for restricting its consumption to an absolute minimum. The Mayo document is titled “Added Fructose” but its subtitle says it all: “A Principal Driver of Type 2 Diabetes Mellitus and Its Consequences.” Those consequences include obesity, metabolic disorders, and cardiovascular disease.

What is HFCS?

High-fructose corn syrup is a highly engineered form of cornstarch. The cornstarch is treated with chemicals and enzymes that cause its natural sugars (glucose) to break down into smaller molecular components of fructose, the form of sugar naturally found in fruits and some vegetables. The problem with the HFCS is that it is much sweeter than the fructose Mother Nature makes. The human body is itself engineered to process fructose but only in its natural form.

Natural or Added Sugar?

Natural sugars are those that occur naturally in foods, such as the natural sweetness of fruits, tomatoes, sweet potatoes, milk, and other naturally sweet foods. Added sugar is any sugar in any form (natural or engineered) that is added to a food or beverage to alter its natural flavor.

Fructose content in fruits accounts for 5% to 10% of the weight of the fruit. Many sugar-added foods and beverages contain a much higher concentration of HFCS; some sweetened beverages are almost 100% HFCS. When confronted with this abundance of HFCS, the body’s battle to maintain healthy levels of blood sugars leads to insulin resistance which leads to impaired health.

Why the Controversy?

Advocates for a safe food supply say that since HFCS does not occur in nature, it is not real food and should be identified on the ingredients lists of all foods and beverages that contain it. Food manufacturers don’t want to identify it in all cases because it is inexpensive to make and manipulate; they like using it and don’t want consumers to stop buying HFCS-laced products. HFCS is found in almost all packaged foods and beverages including sweetened soft drinks, coffees, teas, waters, and juices as well as most pre-made food products including sweets and pastries but it’s also in soups, pizza, mac and cheese, stuffing mixes, bread, condiments and sauces, dairy products, and meat-based products that include kid-friendly Oscar Mayer Lunchables.

In 2006, food advocates petitioned the US Food and Drug Administration (FDA) for a streamlined definition of “natural” and “all natural” ingredients, with HFCS to be identified as an artificial ingredient. The FDA would not agree to this request but food manufacturers, including the Corn Refiners Association, voluntarily changed many of their ingredients lists to avoid claiming HFCS; many labels now list the engineered sugar as maize sugar, corn sugar, natural sugar, or natural flavor.

What Do the Mayo Doctors Want?

The Mayo paper calls for reducing consumption of HFCS to no more than 5% of one’s daily total caloric intake. The World Health Organization already recommends this amount. The American Diabetes Association and some US government agencies, however, recommend no more than 25% of one’s daily caloric intake to include HFCS-sweetened food and beverage products.

Today, one in ten adults worldwide has type 2 diabetes. Food-grade HFCS was introduced to the market in 1970 and the rate of type 2 diabetes has skyrocketed since then. By 1980, 153 million people were diagnosed with type 2 diabetes; by 2008, the number doubled to 347 million people around the world.

In the US, one in 11 adults (29 million) has type 2 diabetes and 86 million (one in three) are pre-diabetic. Once considered a disease of middle age, it is no longer unusual for children to be diagnosed with type 2 diabetes.


  1. DiNicolantonio, James J., James H. O'Keefe, and Sean C. Lucan. "Added Fructose: A Principal Driver of Type 2 Diabetes Mellitus and Its Consequences." Mayo Clinic Proceedings. Mayo Foundation for Medical Education and Research, 29 Jan. 2015. Elsevier Inc.. Web. 23 Feb. 2015.
  2. "More than 29 million Americans have diabetes; 1 in 4 doesn’t know." CDC Newsroom. Centers for Disease Control and Prevention, 10 June 2014. Web. 23 Feb. 2015.