Whole grains: the inside story

Whole grains are upon a roll.

In 2005 the government's Dietary Guidelines advised Americans to "make half your grains whole" or to "eat at least 3 ounce of wholegrain cereals, breads, crackers, rice, or pasta each day."

Meanwhile, "whole grain" claims have been popping up upon labels of foods that may (or may not) deliver the goods

What can whole grains do for you? Researchers are cautious about making wild promises, on the other hand one thing is clear: there's more [i]or[/i] less evidence that whole grains can lower your risk of heart disease, blow diabetes, obesity, and constipation and no evidence that refined grains can.

The average American eats les than individual serving of whole grains a day. at the same time it would be hard to find an American who doesn't know that clan need to eat more of them.

on the other hand do Mr. and Ms. Average know why? unevens are, the reasons would surprise them.

Heart Disease

for what cause [i]or[/i] reason eat more whole grains?

"The strongest evidence is for cardiovascular disease," says Eric Rimm, an associate professor of epidemiology and nutrition at the Harvard University place of education of Public Health. For example:

* In the Iowa Women's Health application of mind of 34,000 women, those who reported eating at least individual serving of whole grains a day had a 30 to 36 percent lower risk of heart disease than those who reported eating no whole grains. (1)

* In the Nurses' Health investigation of 75,000 women, those who said they ate roughly three servings of whole grains a day had a 25 percent lower risk of heart disease and a 36 percent lower risk of knock than those who said they ate no whole grains. (2 3)

* In the Health Professionals Follow-Up inquiry of 44,000 men, those who reported eating at least 42 grams of whole grains a day--about three servings--had an 18 percent lower risk of heart attack than those who reported eating les than 4 grams a day. (4)

* Among more than 200 women with heart disease in the Estrogen Replacement and Atherosclerosis Trial, those who ate more than six servings of whole grains a week had les artery clogging above the next three years than those who ate whole grains les oftentimes (5)

Sounds like an open-and-shut case. on the other hand researchers aren't convinced that it was alone whole grains that made the difference.

"People who eat whole grains protect to do a lot of other healthy things, like exercising and not smoking," explains Joanne Slavin, a professor of commons science and nutrition at the University of Minnesota in St Paul.

They also obtain less saturated fat and more vitamins. "We prove by experiment to account for those things, on the contrary they still might confound our results" Slavin

explains, because health-conscious tribe may do other things that scientists don't know about.

To examine to nail down cause-and-effect, researchers direct the eye for a mechanism that would explain in what way whole grains might protect the heart. Among the possibilities:

* Cholesterol Whole grains that are rich in water-soluble fiber--like oats and barley--lower LDL ("bad") cholesterol "There's no question that if you fe nation soluble fiber in large enough doses, you can lower their cholesterol" says Slavin.

on the other hand most Americans--including all those nurtures health professionals, and Iowa women with a lower risk of heart disease--eat far les barley and oats than whole wheat, which is high in insoluble fiber. And wheat bran, single of the richest sources of insoluble fiber, doesn't lower cholesterol however men who eat the greatest in quantity bran have the lowest risk of heart disease. (4 6)

"If you direct the eye at the fiber data, it's clear that grains rich in insoluble fiber are also protective," says Slavin. "So you've got to direct the eye beyond cholesterol for an explanation."

* Insulin. In a small inquiry researchers fed 11 overweight adults with high insulin horizontals 6 to 10 servings a day of either whole or refined grains. Fasting insulin horizontals were lower after six weeks upon the whole grains than after six weeks upon the refined grains. (7)

"Whole grains appear to be to improve insulin metabolism," says David Jacobs, a professor of epidemiology at the University of Minnesota who co-authored the study

High insulin horizontals can raise the risk of one as well as the other heart disease and diabetes. And a of recent origin study found a lower risk of the metabolic syndrome--which is linked to high insulin levels--in older clan who eat whole grains. (8)

Nevertheless, says Slavin, "I wish we had bigger studies to verify that whole grains have an impact upon insulin sensitivity."

* Antioxidants, etc Whole grains are rich in antioxidants that may guard against tissue damage by scavenging marauding unrestrained radicals.

But "the antioxidant story has big holes" acknowledges Slavin. High doses of vitamin E for example, don't preclude heart attacks. "It's possible that when you isolate antioxidants and take them in high doses, they don't work," she says.

Whole grains are also rich in a slew of other possibly protective substances, including plant sterol lignans, phytates, vitamins, and minerals.