Whole grains are in the midst of a renaissance. Since their 1970s heyday, the findings from scientific research have expanded on these fiber-rich foods' abilities to help protect against heart disease, type 2 diabetes, and obesity. Such results led the government to urge us all, in its 2005 dietary guidelines, to eat at least three servings of whole grains daily.
Joanne Slavin, R.D., Ph.D. -- one of the country's foremost experts on fiber and whole grains -- recalls grain's first go-round. "I was in graduate school pursuing a nutrition degree. This was during the mid-1970s, and there was a ton of interest in fiber then," she says. "I thought that by the time I got my doctorate degree everyone would be eating to get enough fiber."
Not so. Most of us still average just one serving of whole grains a day. As a professor of food science and nutrition at the University of Minnesota-St. Paul, she finds she has to spread the word. "Many people have questions about whole grains and how to work them into their diets," she says.
To help answer them, we asked Slavin, along with several other experts, to provide a primer on successfully choosing and cooking with whole grains.
What are whole grains? Whole grains are made of three parts: the bran (or outer layer), the germ, and the endosperm. "In order for a grain to be considered whole, it must contain all three components of the grain," says Nicola McKeown, Ph.D., a scientist who studies whole grains at Tufts University in Boston, Massachusetts. Together the bran, germ, and endosperm contribute to whole grains' high levels of nutrients, nutty taste, and dense, chewy texture.
How do whole grains affect health? In addition to digestive health, whole grains have also been linked to the following benefits:
1. Preventing heart disease. "People with high intake of grains have much less heart disease," Slavin says. A meta-analysis published last year in the journal Nutrition, Metabolism and Cardiovascular Diseases found that 2 ½ servings of whole grains a day were associated with a 21 percent decrease in the risk of developing heart disease. People who ate mostly refined grains did not experience the same results, says study author Philip Mellen, M.D., assistant professor at the Wake Forest School of Medicine in Winston-Salem, North Carolina. Mellen attributes the benefit to synergy. "The combination of whole grains' nutrients work together to reduce cardiovascular disease," he says.
2. Dodging diabetes. When you eat foods that cause a rapid increase in blood sugar (glucose), the pancreas responds by producing insulin. Foods made with refined grains, such as white breads or baked goods, are processed into glucose more quickly than whole-grain foods. "Over time, you can develop insulin resistance, a precursor to type 2 diabetes," McKeown says. "Foods that are rich in fiber blunt the insulin response, and people with a higher whole-grain intake have less risk of developing type 2 diabetes," she says.
3. Maintaining a healthy weight. "Whole-grain foods high in fiber delay hunger, so maybe you'll eat less over the course of the day," McKeown says. Because fiber is indigestible, it adds bulk to foods, which in turn slows down digestion. The result: You feel fuller longer after eating fiber-rich foods. Bonus: Maintaining a healthy weight can also help you avoid health problems such as heart disease and diabetes. (CNN.com)
Joanne Slavin, R.D., Ph.D. -- one of the country's foremost experts on fiber and whole grains -- recalls grain's first go-round. "I was in graduate school pursuing a nutrition degree. This was during the mid-1970s, and there was a ton of interest in fiber then," she says. "I thought that by the time I got my doctorate degree everyone would be eating to get enough fiber."
Not so. Most of us still average just one serving of whole grains a day. As a professor of food science and nutrition at the University of Minnesota-St. Paul, she finds she has to spread the word. "Many people have questions about whole grains and how to work them into their diets," she says.
To help answer them, we asked Slavin, along with several other experts, to provide a primer on successfully choosing and cooking with whole grains.
What are whole grains? Whole grains are made of three parts: the bran (or outer layer), the germ, and the endosperm. "In order for a grain to be considered whole, it must contain all three components of the grain," says Nicola McKeown, Ph.D., a scientist who studies whole grains at Tufts University in Boston, Massachusetts. Together the bran, germ, and endosperm contribute to whole grains' high levels of nutrients, nutty taste, and dense, chewy texture.
How do whole grains affect health? In addition to digestive health, whole grains have also been linked to the following benefits:
1. Preventing heart disease. "People with high intake of grains have much less heart disease," Slavin says. A meta-analysis published last year in the journal Nutrition, Metabolism and Cardiovascular Diseases found that 2 ½ servings of whole grains a day were associated with a 21 percent decrease in the risk of developing heart disease. People who ate mostly refined grains did not experience the same results, says study author Philip Mellen, M.D., assistant professor at the Wake Forest School of Medicine in Winston-Salem, North Carolina. Mellen attributes the benefit to synergy. "The combination of whole grains' nutrients work together to reduce cardiovascular disease," he says.
2. Dodging diabetes. When you eat foods that cause a rapid increase in blood sugar (glucose), the pancreas responds by producing insulin. Foods made with refined grains, such as white breads or baked goods, are processed into glucose more quickly than whole-grain foods. "Over time, you can develop insulin resistance, a precursor to type 2 diabetes," McKeown says. "Foods that are rich in fiber blunt the insulin response, and people with a higher whole-grain intake have less risk of developing type 2 diabetes," she says.
3. Maintaining a healthy weight. "Whole-grain foods high in fiber delay hunger, so maybe you'll eat less over the course of the day," McKeown says. Because fiber is indigestible, it adds bulk to foods, which in turn slows down digestion. The result: You feel fuller longer after eating fiber-rich foods. Bonus: Maintaining a healthy weight can also help you avoid health problems such as heart disease and diabetes. (CNN.com)
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