What Does the Science Say?

The 1990s was the low-fat decade. All we heard was how important it was for us to reduce our intake of dietary fats. Yet the number of Americans that are overweight and obese has increased.

Now, it seems like every week a new study about dietary sugars grabs the headlines, which is making people concerned about sugar. The truth is, a single study on any subject is not conclusive and needs further investigation nor is it a reason to change behavior.

Sugar has been an important ingredient in people’s diets for centuries and the subject of countless studies. When the full body of science is evaluated during a major review of scientific literature, experts continue to conclude that sugars intake is not a causative factor in any disease, including obesity.

In 2002, the National Academy of Sciences concluded that there was insufficient evidence to set an upper level for sugar intake, based on data available on dental caries, behavior, cancer, risk of obesity and risk of hyperlipidemia. This conclusion resulted from a three-year comprehensive review that cited 279 references on dietary carbohydrates. The study found “no clear and consistent association between increased intakes of added sugars and [body mass index].”

This conclusion was just reaffirmed in March 2010 by the European Food Safety Authority expert panel, which also concluded: “Available data do not allow the setting of an UL (upper level) for total or added sugars, neither an AI (Adequate Intake) nor a recommended intake range.”

Past major reviews

In 1986, the FDA Sugars Task Force, in a review of 1000 scientific papers, reported that “with the exception of dental caries, the scientific evidence clears sugars of links with other diseases including diabetes, hypertension, behavior and obesity.”

The 1989 National Academy of Sciences Report on Diet and Health stated that for those with an adequate diet, sugar consumption has not been established as a risk factor for any chronic disease other than dental caries.

In 1997, a joint FAO/WHO expert consultation also found “no evidence of direct involvement of sucrose, other sugars and starch in the etiology of lifestyle diseases.”

Clearly, individuals can enjoy sugar as part of a balanced, nutritious diet without fear of negative health effects. Even people with diabetes can enjoy sugar-sweetened foods.

The 2004 American Diabetes Association position paper advises, “intake of sucrose and sucrose containing foods by people with diabetes does not need to be restricted because of concern about aggravating hyperglycemia. Sucrose should be substituted for other carbohydrate sources in the food/meal plan or, if added to the food/meal plan, adequately covered with insulin or other glucose-lowering medication.”

The scientific evidence is clear, dietary sugars per-se pose no direct negative health impact. Furthermore, sugar makes many healthful foods palatable, which helps contribute to intakes of key vitamins and minerals necessary to maintain good health. Sugar in moderation can be a part of a balanced, healthful diet and lifestyle.