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3.7: Carbohydrates and Personal Diet Choices

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    1851
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    Skills to Develop

    • Define the Acceptable Macronutrient Distribution Range for carbohydrates, the Adequate Intake for fiber, and recommended intake of added sugars.
    • List five foods that are good sources of slow-releasing carbohydrates.
    • Identify three to five foods high in fiber and carbohydrates from whole, unrefined sources.

    In this chapter, you learned what carbohydrates are, the different types of carbohydrates in your diet, and that excess consumption of some types of carbohydrates cause disease while others decrease disease risk. Now that we know the benefits of eating the right carbohydrate, we will examine exactly how much should be eaten to promote health and prevent disease.

    How Many Carbohydrates Does a Person Need?

    The Food and Nutrition Board of IOM has set the Recommended Dietary Allowance (RDA) of carbohydrates for children and adults at 130 grams per day. This is the average minimum amount the brain requires to function properly. The Acceptable Macronutrient Distribution Range (AMDR) for carbohydrates is between 45 and 65 percent. This means that on a 2,000 kilocalorie diet, a person should consume between 225 and 325 grams of carbohydrate each day. According to the IOM, not more than 25 percent of total calories consumed should come from added sugars. The World Health Organization and the AHA recommend much lower intakes of added sugars—10 percent or less of total calories consumed. The IOM has also set Adequate Intakes for dietary fiber, which are 38 and 25 grams for men and women, respectively. The recommendations for dietary fiber are based upon the intake levels known to prevent heart disease.

    Table 3.7.1: Dietary Reference Intakes for Carbohydrates and Fiber
    Carbohydrate Type RDA (g/day) AMDR (% calories)
    Total Carbohydrates 130 45–65
    Added Sugars < 25
    Fiber 38 (men),* 25 (women)*
    * denotes Adequate Intake

    When Carbohydrate Intake is Inadequate

    Inadequate intake of carbohydrate lowers blood glucose. To maintain blood glucose, the liver breaks down glycogen to release glucose and liver glycogen stores can become depleted. Also, certain amino acids are released from muscle protein and used to make glucose. This process is called catabolism. Finally, fat is mobilized from fat stores and the released fatty acids are converted to ketones in the liver and used as an energy source. This is not the body's preferred energy source.

    Low Carbohydrate Diets

    Some weight loss diets, for example, Atkins, South Beach, and Sugar Busters, recommend a low carbohydrate intake. Since carbohydrate is low one of the other macronutrients is excessive, usually protein. Generally, these diets are also low in calories too and this promotes the weight loss, not the reduced carbohydrate content. Side effects of these diets include halitosis (bad breath), constipation fatigue, nausea, dizziness and bone loss.

    Dietary Sources of Carbohydrates

    Carbohydrates are contained in all five food groups: grains, fruits, vegetables, meats, and beans (only in some processed meats and beans), and dairy products. Fast-releasing carbohydrates are more prevalent in fruits, fruit juices, and dairy products, while slow-releasing carbohydrates are more plentiful in starchy vegetables, beans, and whole grains. Fast-releasing carbohydrates are also found in large amounts in processed foods, soft drinks, and sweets. On average, a serving of fruits, whole grains, or starches contains 15 grams of carbohydrates. A serving of dairy contains about 12 grams of carbohydrates, and a serving of vegetables contains about 5 grams of carbohydrates. Table 3.7.2 gives the specific amounts of carbohydrates, fiber, and added sugar of various foods.

    Table 3.7.2: Carbohydrates in Foods (grams/serving)
    Foods Total Carbohydrates Sugars Fiber Added Sugars
    Apple 19 (1 medium) 19.00 4.4 0
    Banana 27 (1 medium) 14.40 3.1 0
    Lentils 40 (1 c.) 3.50 16.0 0
    Snap beans 8.7 (1 c.) 1.60 4.0 0
    Green pepper 5.5 (1 medium) 2.90 2.0 0
    Corn tortilla 10.7 (1) 0.20 1.5 0
    Bread, wheat bran 17.2 (1 slice) 3.50 1.4 3.4
    Bread, rye 15.5 (1 slice) 1.20 1.9 1.0
    Bagel (plain) 53 (1 medium) 5.30 2.3 4.8
    Brownie 36 (1 square) 20.50 1.2 20.0
    Oatmeal cookie 22.3 (1 oz.) 12.00 2.0 7.7
    Cornflakes 23 (1 c.) 1.50 0.3 1.5
    Pretzels 47 (10 twists) 1.30 1.7 0
    Popcorn (homemade) 58 (100 g) 0.50 10.0 0
    Skim milk 12 (1 c.) 12.00 0 0
    Cream (half and half) 0.65 (1 Tbs.) 0.02 0 0
    Cream substitute 1.0 (1 tsp.) 1.00 0 1.0
    Cheddar cheese 1.3 (1 slice) 0.50 0 0
    Yogurt (with fruit) 32.3 (6 oz.) 32.30 0 19.4
    Caesar dressing 2.8 (1 Tbs.) 2.80 0 2.4

    Sources: US Department of Agriculture. National Nutrient Database for Standard Reference. Last modified December 7, 2011. http://www.nal.usda.gov/fnic/foodcomp/search/, and US Department of Agriculture. "Database for the Added Sugars Content of Selected Foods." February 2006. http://www.nal.usda.gov/fnic/foodcomp/search/.

    It’s the Whole Nutrient Package

    In choosing dietary sources of carbohydrates the best ones are those that are nutrient dense, meaning they contain more essential nutrients per calorie of energy. In general, nutrient-dense carbohydrates are minimally processed and include whole-grain breads and cereals, low-fat dairy products, fruits, vegetables, and beans. In contrast, empty-calorie carbohydrate foods are highly processed and often contain added sugars and fats. Soft drinks, cakes, cookies, and candy are examples of empty-calorie carbohydrates. They are sometimes referred to as ‘bad carbohydrates,’ as they are known to cause health problems when consumed in excess.

    Interactive 3.7.1

    This interactive USDA tool allows you to enter the foods and serving size of what you’re eating and find out the whole nutrient package.

    http://www.ars.usda.gov/Services/docs.htm?docid=17032

    Understanding Carbohydrates from Product Information

    While nutrition facts labels aid in determining the amount of carbohydrates you eat, they do not help in determining whether a food is refined or not. The ingredients list provides some help in this regard. It identifies all of the food’s ingredients in order of concentration, with the most concentrated ingredient first. When choosing between two breads, pick the one that lists whole wheat (not wheat flour) as the first ingredient, and avoid those with other flour ingredients, such as white flour or corn flour. (Enriched wheat flour refers to white flour with added vitamins.) Eat less of products that list HFCS and other sugars such as sucrose, honey, dextrose, and cane sugar in the first five ingredients. If you want to eat less processed foods then, in general, stay away from products with long ingredient lists. On the front of food and beverages the manufacturers may include claims such as “sugar-free,” “reduced sugar,” “high fiber,” etc.. The Nutrition and Labeling Act of 1990 has defined for the food industry and consumers what these labels mean (Table 4.7.3).

    Table 3.7.3: Food Labels Pertaining to Carbohydrates
    Label Meaning
    Sugar-free Contains less than 0.5 grams of sugar per serving
    Reduced sugar Contains 25 percent less sugar than similar product
    Less sugar Contains 25 percent less sugar than similar product, and was not altered by processing to become so
    No sugars added No sugars added during processing
    High fiber Contains at least 20 percent of daily value of fiber in each serving
    A good source of fiber Contains between 10 and 19 percent of the daily value of fiber per serving
    More fiber Contains 10 percent or more of the daily value of fiber per serving

    The Bottom Line

    Read the labels and ingredient lists of foods to determine your carbohydrate intake and know the types of carbohydrate you consume.

    Personal Choices

    Carbohydrates are in most foods so you have a great variety of choices with which to meet the carbohydrates recommendations for a healthy diet. The 2010 Dietary Guidelines recommends eating more unrefined carbohydrates and more fiber, and reducing consumption of foods that are high in added sugars. To accomplish these recommendations use some or all of the following suggestions:

    • Get more daily carbohydrate servings from whole grains by eating a whole-grain cereal for breakfast, using whole-grain bread to make a sandwich for lunch, and eating a serving of beans and/or nuts with dinner.
    • Make sure to get at least three servings (or more) of all the grains you eat as whole grains every day. A serving of whole grains is equal to one slice of whole-wheat bread, one ounce of whole-grain cereal, and one-half cup of cooked cereal, brown rice, or whole-wheat pasta.
    • Food products made with cornmeal use the whole grain so choose tortillas, corn cereals, and corn breads with cornmeal listed as the first ingredient.
    • When baking, substitute whole-wheat flour or other whole-grain flour for some of the refined white flour.
    • If you like bread at dinner, choose a whole-grain muffin over a Kaiser roll or baguette.
    • Add beans, nuts, or seeds to salad—they add texture and taste.
    • Choose whole-grain pastas and brown rice, cook al dente, and add some beans and vegetables in equal portions.
    • Change it up a bit and experience the taste and satisfaction of other whole grains such as barley, quinoa, and bulgur.
    • Eat snacks high in fiber, such as almonds, pistachios, raisins, and air-popped popcorn.
    • Add an artichoke and green peas to your dinner plate more often.
    • Calm your “sweet tooth” by eating fruits, such as berries or an apple.
    • Replace sugary soft drinks with seltzer water, tea, or a small amount of 100 percent fruit juice added to water or soda water.

    Key Takeaways

    • The IOM has set the Recommended Dietary Allowance of carbohydrates for children and adults at 130 grams per day. This is the average minimum amount the brain requires to function properly. The Acceptable Macronutrient Distribution Range for total carbohydrates is 45 to 65 percent.
    • Carbohydrates are contained in all five food groups: grains, fruits, vegetables, meats and beans (only in some processed meats and beans), and dairy products.
    • The 2010 Dietary Guidelines recommends eating more slow-releasing carbohydrates and more fiber, and reducing consumption of foods that are high in added sugars. This involves choosing carbohydrate sources that are nutrient-dense, with more essential nutrients per calorie of energy.

    Discussion Starters

    1. Are you getting the recommended amount of dietary fiber in your diet?
    2. Visit the USDA “Database for the Added Sugars Content of Selected Foods” and find the added sugar contents of foods common in your diet. Discuss some of the “surprises” that you discover with your classmates.

      www.nal.usda.gov/fnic/foodcomp/Data/add_sug/addsug01.pdf


    3.7: Carbohydrates and Personal Diet Choices is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.