Fructose, or fruit sugar, is the most common naturally occurring form of sugar and is found in fruits and vegetables. While you may know you should avoid excess fructose sugars in your diet, it may be less clear just how much is appropriate. The answer lies in how much synthetic sugar vs how much natural fructose you consume.
Although the term fructose is included in the name, high-fructose corn syrup is not the same as fructose. High-fructose corn syrup is commonly added to products to enhance flavor because it is significantly sweeter than sugar and can be less expensive to produce than sugar. The composition of high-fructose corn syrup is chiefly glucose with less than half being actual fructose. When considering how much fructose you consume each day, keep in mind that products containing this additive are not solely fructose and should be considered as added sugars in your daily diet.
Reasons to Limit
Monitoring your consumption of fructose is important because these fruit sugars have little nutritional value and add calories to our daily diets. Also, fructose does not trigger the same insulin response as other foods that help us to feel full. For this reason, you may find that you eat greater amounts of fructose-containing foods, which means you consume more calories. Excess calories lead to weight gain, which can increase the risk for diabetes and heart disease.
Finding the Fructose
Naturally occurring fructose is found in all fruits, honey and root vegetables, such as sugar cane. Added fructose sugars are not as easy to locate. While nutrition labels list total sugar content, the labels do not differentiate between added and natural sugars. To determine whether your food has added sugars, look at the ingredients listing for items that end in "-ose," raw sugar, corn sweetener, cane sugar or molasses. These indicate that fructose sugars have been added to your food.
The American Heart Association recommends that women eat no more than 100 calories per day from all added sugars, which translates to roughly 6 teaspoons per day. Men should eat no more than 150 calories per day -- about 9 teaspoons per day. Another way to look at this is in terms of nutrition labeling. Each gram of sugar contains about four calories. If your food choice has 20 g of added sugar, you are consuming 80 calories as part of your daily added sugar intake. For naturally occurring sugars, the guidelines are less hard-and-fast. The American Food Guide Pyramid recommends eating five fruits and vegetables per day. Keeping your serving of fruit to two to three servings per day should serve as a healthy intake of fructose.
While fruits contain antioxidants and nutrients that can boost your health, there are certain patient populations that should be cautious about eating fruit. "We tell patients with high cholesterol to be careful with fruit," said Dr. Carel Le Roux, a physician specializing in metabolic medicine, in a Mail Online interview. "Diabetics should also take care, as the high-fructose content can raise blood glucose levels." If you fall into these categories, speak to your physician about how much fructose you can safely consume daily.
- Mayo Clinic: What Are the Health Concerns About High-Fructose Corn Syrup?: Jennifer Nelson: Oct. 23, 2010
- "Mail Online": How Too Much Fruit Can Make You Fat: Simone Cave: March 17, 2010
- American Heart Association: Sugars and Carbohydrates: Oct. 12, 2010
- "Circulation"; Dietary Sugars Intake and Cardiovascular Health: Johnson et. al.; Aug. 24, 2009