Carbohydrate is an Excellent Energy Source ...
What How much carbohydrate do we eat?
In countries such as the United States and Canada about half of the energy adults eat comes by way of carbohydrates and has so for the last few decades with minor fluctuations. About half of this carbohydrate is in the form of starch and the other half in the form of simple sugars. Sucrose makes up about half of the simple sugars we eat. In other areas of the world such as Africa and Asia sucrose consumption makes a lesser contribution while whole grains (e.g., wheat and rice), fruits, and vegetables make a greater contribution. The carbohydrate content of certain types of food is listed in the table below. This includes easily digested carbohydrates such as sugars and starches as well carbohydrates that not easily digested such as oligosaccharides and fibers. Looking at this table we see that “sweets” such as candies and cakes are among those with the highest content of carbohydrate. Furthermore, nearly all of the carbohydrate in these foods comes by way of caloric sweeteners, primarily sucrose for baked sweets which is added as a recipe ingredient. Fruits may be somewhat deceiving; as their carbohydrate content is roughly 5 to 20 percent. However, keep in mind that their water content makes up most of the remaining weight. Therefore carbohydrate is the major non-water content of fruits. Cereal grains and products such as rice, oats, pastas, and breads also have relatively high carbohydrate content. Conversely, animal foods such as meats, fish, and poultry (and eggs) are virtually void of carbohydrate. Animal flesh (skeletal muscle) does contain a little carbohydrate, primarily as glycogen. However, the glycogen is lost during the processing of the meat. As mentioned above, milk and some dairy products (yogurt, ice cream) and honey are the only significant commonly consumed animal-derived carbohydrate providers.
How much sugar are we consuming?
Sugar is part of the diet as naturally occurring sugars, such as fruit, milk and derived foods as well as “added sugar”. Added sugar is either added to foods as a recipe ingredient (e.g. desserts, snacks, soft drinks, beverages, condiments) or added to prepared foods at the table (e.g. cereal, coffee, tea). In a sense, sugar is the number one food additive. It turns up in some unlikely places, such as pizza, bread, hot dogs, boxed mixed rice, soup, crackers, spaghetti sauce, lunch meat, canned vegetables, fruit drinks, flavored yogurt, ketchup, salad dressing, mayonnaise, and some peanut butter. Currently “added sugar” contributes about 16% of calories for children and adults.
The consumption of soft drinks (e.g. soda) are often targeted as the key contributor of added sugar in the diet. However, carbonated sodas provided roughly 20 percent of the added sugars in the American food supply, which is up from 16 percent estimated consumption in 1970. Adult males and females consume roughly 180 and 100 calories from soft drinks daily or about 44 and 25 grams of sugar.
What are the recommendations for carbohydrate consumption?
The recommended range for carbohydrate intake as part of the Dietary Reference Intakes (DRIs) in the U.S. and Canada is 45 to 65 percent of total energy. The breadth of this range allows for different people to plan their diet carbohydrate level based on their level of activity and ability to properly process food carbohydrate (see diabetes). People should focus on “healthier carbohydrate” sources such as whole grain products, fruits and vegetables. These foods provide more natural sources of vitamins, minerals, fiber and phytochemicals relative to digestible carbohydrate content (e.g. starch and sugars) that promote health. Naturally occurring fiber and calcium are often said to be good “look for” nutrients to make choices.
The RDA for carbohydrate energy has been set at 130 grams per day for people of all ages above one year of age. This would provide 520 calories of energy which is important to the central nervous system, red blood cells and other tissue dependent on glucose as their primary energy source. It is important to realize that the RDA recommendation does not take into consideration exercise and additional calorie needs of working muscle nor is it sensitive to delivering key essential and other beneficial nutrients typically derived from carbohydrate containing foods. It just references a level of carbohydrate intake that would meet the base needs of glucose dependent cells in the body and to prevent ketosis, a metabolic situation that occurs when fat becomes the primary energy source for longer periods of time.
What are recommendations for the level of “added sugar” in the diet?
The American Heart Association recommends that added sugar consumption be limited to 100-150 kcal/day. Meanwhile the 2010 Dietary Guidelines state that added sugars and “solid fats” should contribute no more than 5-15% of total calories. Currently, combined they contribute 35% of the calories in the adult diet in the US. Solid fats are mostly saturated fat found in a variety of foods which the thinking that these fats along added sugars deliver mostly incremental energy and thus can be targeted for control relative to diet balance and quality and caloric needs for a healthy body weight .
The World Health Organization has recently lowered its added sugar ceiling recommendation from 10 to 5%. Added sugars, which could be considered the most common food additive is found in a variety of foods in the form of sucrose, corn sweeteners, honey, maple syrup, and molasses. You will find it in some unlikely places, such as pizza, bread, hot dogs, boxed mixed rice, soup, crackers, spaghetti sauce, lunch meat, canned vegetables, fruit drinks, flavored yogurt, ketchup, salad dressing, mayonnaise, and some peanut butter. A can of soda may contain up to 10 teaspoons or 40 grams of sugar. A tablespoon of ketchup has 1 teaspoon of sugar.