Glucose and fructose are both monosaccharides -- simple sugar molecules. Sucrose is a disaccharide made up of two simple sugar molecules, a glucose molecule and a fructose molecule. Sucrose, glucose and fructose may taste similar in food sources such as fruit, honey and candy but are actually quite different.
All Sugars Are Not the Same
Sucrose and high-fructose corn syrup are major sources of fructose and glucose added to foods. Sucrose -- table sugar -- is equal parts fructose and glucose. HFCS is glucose and fructose mixed in different concentrations, the most common being 55 percent fructose and 45 percent glucose. HFCS is in soft drinks and pastries as well as many processed foods. Although too much of any sugar in your diet is not good, researchers of a review study published in 2013 in "Journal of Nutrition and Metabolism" suggest fructose is linked to metabolic syndrome, a combination of medical problems that increase your risk of cardiovascular disease and diabetes when they occur together. HFCS is under scrutiny because manufacturers are not required to specify on food labels for general consumers how much fructose is in the concentration.
Glucose May Be a Lesser Evil
Researchers of a study at the University of California Davis published in 2008 in "The American Journal of Clinical Nutrition" compared the effects on monkeys of consuming beverages sweetened with fructose, glucose, sucrose and HFCS. Glucose did not increase triglycerides, which are fats or lipids in your blood, as much as the other sweeteners, which all contain fructose. Later in a study published in 2011 in "The Journal of Clinical Endocrinology and Metabolism," again at UC Davis, researchers found that beverages sweetened with HFCS or with fructose increased blood lipids in adult humans in just two weeks, while beverages sweetened with glucose did not.
Fructose -- Not So Sweet
Fructose has been linked to more than one parameter associated with the metabolic syndrome. Researchers of the 2013 "Journal of Nutrition and Metabolism" review study found that fructose may increase uric acid in your blood, while researchers of a study published in 2011 in "Annals of the New York Academy of Sciences" stated fructose is associated with increased abdominal obesity, abnormal blood lipids and insulin resistance.
Reduce Your Risk for Metabolic Syndrome
A good way to decrease your risk of metabolic syndrome is to reduce added sugars in your diet. Added sugars are those not found naturally in fruits, vegetables, grains and milk, so eat mainly fresh foods and limit your intake of processed foods. If you do happen to eat processed food, read the ingredients list for added sugar, which may appear as a name other than just sugar. Some words to look out for are those ending with "ose," such as sucrose and maltose, as well as high-fructose corn syrup, corn syrup, molasses and honey.
- Colorado State University Extension: Sugar and Sweeteners
- The American Journal of Clinical Nutrition: Endocrine and Metobolic Effects of Consuming Beverages Sweetened With Fructose, Glucose, Sucrose, or High-Fructose Corn Syrup
- The Journal of Clinical Endocrinology and Metabolism: Consumption of Fructose and High Fructose Corn Syrup Increase Postprandial Triglycerides, LDL-Cholesterol, and Apolipoprotein-B in Young Men and Women
- UC Davis Health System: Fructose Consumption May Impact Development of Metabolic Syndrome
- Journal of Nutrition and Metabolism: Fructose: A Key Factor in the Development of Metabolic Syndrome and Hypertension
- The Journal of Clinical Investigation: Consuming Fructose-Sweetened, Not Glucose-Sweetened Beverages Increases Visceral Adiposity and Lipids and Decreases Insulin Sensitivity in Overweight/Obese Humans
- Annals of the New York Academy of Sciences: Fructose Consumption: Recent Results and Their Potential Implications
- American Heart Association: Added Sugars