Fructose has been the object of controversy for some time, both within the diabetes community and in the broader conversation on nutrition. Found naturally in fruits and some vegetables, this sugar is added in refined forms to many beverages and processed foods (usually as high-fructose corn syrup) and is also available in pure granular form. It has been touted by some people with diabetes for its sweetness — it is sweeter than sucrose (table sugar) — and for its mild effect on blood glucose levels. Its glycemic index value is 19, compared with 65 for sucrose.
But this low glycemic impact may actually hint at why fructose is associated with certain problems: Fructose is not readily used by the body for energy and must therefore be processed by the liver, which often turns fructose into triglycerides, the body’s main form of stored fat. Consuming large amounts of fructose, not surprisingly, has been associated with high blood triglyceride levels. A new study has also found, however, that fructose in the diet increases the risk of high blood pressure. In the study, published in the Journal of the American Society of Nephrology, researchers analyzed surveys that 4,528 adults with no recorded history of elevated blood pressure had completed. They calculated the amount of fructose from added sugars in participants’ diets and compared this with their blood pressure level, which was measured as part of the survey. After controlling for numerous factors — including physical activity level, caloric intake, carbohydrate intake, illnesses, and demographic information — the researchers found that participants who consumed fructose at or above the median level of 74 grams per day had a 28% higher risk of prehypertension, defined by a blood pressure reading of 135/85 or above. The risk of high blood pressure, defined as 140/90 or above, was 30% higher, and the risk of extremely high blood pressure, 160/100 or above, was 77% higher.
The methods used by the researchers to calculate the amount of fructose in the diet for this study were disputed by the Corn Refiners Association, according to a Reuters article. High-fructose corn syrup actually provides about the same amount of fructose as sucrose does, when one considers that sucrose molecules are actually fructose molecules bonded with glucose molecules, and this bond is quickly dissolved in the body. Nevertheless, sucrose was not counted as part of fructose intake for this study, making any fructose-related effect from high-fructose corn syrup all the more striking. Fruit, it should be noted, generally contributes a small amount of fructose to the diet compared with beverages and processed foods that contain high-fructose corn syrup.
What do you think — do you avoid fructose, or high-fructose corn syrup, in your food or drinks? Or have you found fructose in a purified form to have benefits? Do you restrict your intake of any fruits or fruit juices? Do you look at fructose specifically in your diet, or just keep tabs on overall sugar intake? If you have reduced your fructose intake, have you noticed any benefits? Leave a comment below!