Why Is Starch Good for the Body?

Market stallholder selling bread to customer, close-up

There are three types of carbohydrates: fiber, sugars and starch. While many weight-loss diets suggest heavy restriction of starch and other carbs, the notion that carbohydrates themselves are fattening is a myth, says the Weight-Control Information Network. Many starchy foods are highly nutritious and bring valuable benefits to a healthy diet.

How Starches Work

Carbohydrates are your body's primary fuel source. After you eat, your digestive system converts them into glucose, or blood sugar, which your body uses to energize your tissues, cells and organs. Whatever is leftover is stored in your liver and muscles for later use. As a complex carbohydrate source, starchy foods, often simply called starches, tend to be high in fiber -- a carbohydrate that promotes healthy digestive function and blood sugar control. Complex carbohydrate sources break down slower than simple carbohydrates, such as sugar and juice, providing longer-lasting energy and fullness between meals.

Healthy Starch Sources

Foods high in starch include legumes, such as beans and lentils, vegetables, such as potatoes and butternut squash, and grains, such as rice and flour. Whole foods containing starch, including vegetables, legumes and whole grains, are valuable sources of fiber, vitamins, minerals and antioxidants. One medium baked sweet potato with the peel provides over 2 grams of protein, nearly 4 grams of fiber and rich amounts of vitamin A. Legumes and whole grains also provide richer amounts of protein. Particularly nutritious whole-grain foods include brown rice, air-popped popcorn, quinoa and 100 percent whole-grain breads and cereals.

Sources to Avoid

Not all starchy foods are chock-full of nutrients. When grains are refined to make processed foods, such as white flour and instant rice, the starchy part is removed, lessening the its nutritional content significantly. Americans consume too many refined grains, according to the 2010 Dietary Guidelines for Americans, and a healthy diet limits them, leaving more room for nutritious fare. To avoid weight gain, Type 2 diabetes and other risks of eating too many refined grains, limit or avoid foods that list refined grains, such as white or enriched flour, as the main ingredient. Common examples include egg noodles, saltines, pretzels, cookies, cakes and cornflakes.

How Much to Eat

To meet your basic nutritional needs, the 2010 Dietary Guidelines for Americans recommends making sure that at least half of the grains you eat are whole grains. This is equal to at least 3 ounces per day for women and men over age 50 and at least 3.5 to 4 ounces per day for younger men. Overall, carbohydrates should account for 45 to 65 percent of your diet. Based on a 2,000-calorie diet, this amounts to 900 to 1,300 calories daily or 225 to 325 grams. If you eat 1,500 calories per day, this amounts to 675 to 975 calories or 169 to 244 grams.