Glucose belongs to a class of nutrients known as monosaccharides or simple sugars. As it circulates in our blood stream, glucose--or dextrose--acts as a vital source of energy for different cells including neurons (brain cells) and red blood cells. The human body works hard to maintain glucose homeostasis--a term referring to constant glucose levels. This is important because abnormal blood glucose levels cause symptoms ranging from headaches to mental confusion. To avoid such complications, it is imperative to consume adequate levels of glucose from food.
Grains
Glucose is rarely found in food in its single molecular form. Instead, it is found as a monomer or building block for more complex carbohydrates. Grain products such as bread, pasta, cereals and rice contain starch and fiber, which, in turn, are composed of thousands of glucose units linked together in chains. As we ingest such foods, the digestive system breaks down those complex carbohydrates into single glucose units to be utilized by our cells as needed.
Fruits & Vegetables
Glucose is found in varying quantities in most fruits and vegetables. Examples include, but are not limited to, figs, dates, apricots, apples, peppers, tomatoes and onions. Grapes are an especially rich source of glucose. So much so that glucose is sometimes referred to as grape sugar.
Dairy Products
Glucose occurs in milk and dairy products as part of the disaccharide (double sugar) lactose.
Refined Sugars
Glucose is also a component of table sugar or sucrose. This means that glucose is found in all foods containing sugar such as candy, baked goods and soft drinks. It is important to note however that the United Stated Department of Agriculture strongly recommends limiting the consumption of such high-sugar foods as part of an overall healthy diet.
Other Foods
Other sources of dietary glucose include honey, maple syrup, pancake mixes, commercial salad dressings and spices.
References
- USDA: Dietary Guidelines For Americans
- "Nutrition Concepts & Controversies"; F. Sizer & E. Whitney; 2006
- Top 200 Foods: Sources of Glucose
