Health Benefits of Whole Grains

Nutrition experts – including those advising this newsletter – have been preaching for years about the benefits of replacing refined grains in your diet with whole grains. The latest Dietary Guidelines for Americans echoed this advice, recommending limiting intake of refined grains and products made with refined grains and starches. People consuming a healthy US-style eating pattern at a 2,000-calorie level, according to the guidelines, can consume six ounces (or the equivalent) of grains per day. And at least half of those should be whole grains.

“There are many benefits associated with higher whole grain intake and lower refined grain intake,” says Alice H. Lichtenstein, DSc, director of Tufts’ HNRCA Cardiovascular Nutrition Laboratory and executive editor of the Health & Nutrition Letter. “Sometimes it seems like the evidence bounces around, but looking at the totality, whole grains come out on top.

“Fortunately, for most refined grain products there is a whole grain alternative that is readily available,” she adds. “There is no need to go hunting any more for the best choices. And, for those people who are holdouts, once they try the whole grain version they find it is more interesting, in both texture and taste.”

More than half the population, the updated guidelines noted, meets or exceeds recommended intakes for total grains – but most fall short in consuming whole grains. For the average American, consumption of whole grains remains below one serving a day.

WHY IS IT IMPORTANT TO EAT WHOLE GRAINS?:

Why are whole grains so much better for you? Whole grains or foods made from them contain all the essential parts and naturally occurring nutrients of the entire grain seed in their original proportions. That means you’re getting 100% of the original kernel – all of the bran, germ and endosperm. Unlike refined grains, which strip away the outer bran and germ, leaving just the starch, whole grains retain all the natural nutrition of grains such as wheat, brown rice, barley, oats, etc. (see box). Although nutrients vary by type of grain, this means that whole grains are generally higher in dietary fiber, iron, potassium, magnesium, calcium, B vitamins and vitamin E.

It’s easy to start increasing your intake. Of course, even healthy whole grains contain carbs and calories, so instead of simply piling more food on your plate, you should substitute whole grain products for the refined grain foods you’re already eating. You’ll reach or exceed the recommendations pretty quickly. Consider a typical day’s meals:

– Choose steel-cut oatmeal or a whole grain ready-to-eat cereal for breakfast.

– Make your lunchtime sandwich with 100% whole-wheat bread.

– Snack on whole grain crackers or popcorn (hold the butter and go easy on the salt).

– Instead of white rice or refined grain pasta with dinner, choose brown rice or wild rice, which are both whole grains, or whole-wheat pasta. Consider trying less-familiar, delicious whole grains like millet, barley, farro and others.

For a discussion on which whole grains to consider for your morning breakfast, The New York Times “Well” section recently quoted Tufts’ Dean Dr. Dariush Mozafffarian on the topic.

“If you eat a breakfast of refined cereal and skim milk,” Dr. Mozaffarian says, “your blood sugar is going to crash a few hours later, and you will be hungrier and eat more for lunch.”

It’s better to aim for a carbohydrate-to-fiber ratio of ten to one, he says. Cheerios and oatmeal achieve this ratio. But use caution: Instant oat meals have a lot of sugar.

DEFINITION OF WHOLE GRAINS:

Studies use different definitions of a “serving” of whole grains, and it can be confusing to keep track of how much you’re actually getting. One common guide is the 100% Whole Grain Stamp, which identifies products containing at least 16 grams of whole grains per serving. (There is also a “Basic” stamp, which products containing 8 grams of whole grains can display.)

But products with this stamp also contain, on average, higher levels of sugar and calories than other choices. A better rule is to look for products that have, per serving, at least 1 gram of fiber for every 10 grams of total carbohydrate (“10:1 ratio”). For example, if a serving has 20 grams of total carbs, it should have at least 2 grams of fiber. If it has 40 grams of carbohydrates, then it should have at least 4 grams of fiber. (For the research behind this rule, see <www.ncbi.nlm.nih.gov/pubmed/23286205>).

Otherwise, recommendations generally define a single serving of whole grains as, for example:

– 1/2 cup cooked brown rice or other cooked grain

– 1/2 cup cooked 100% whole grain pasta

– 1/2 cup cooked hot cereal, such as oatmeal

– 1 ounce uncooked whole grain pasta, brown rice or other grain

– 1 slice 100% whole grain bread

– 1 very small (1 ounce) 100% whole grain muffin (“mini muffin”)

– 1 cup 100% whole grain ready-to-eat cereal.

HEALTH BENEFITS OF WHOLE GRAINS:

However you count them, the latest evidence for the health benefits of whole grains is compelling: Recent studies have associated whole grain consumption with lower risk of mortality and of chronic diseases such as heart attack, other cardiovascular disease, cancer and type 2 diabetes.

One study, published in the American Heart Association’s journal Circulation, reported that eating at least three servings of whole grains (48 grams) every day was associated with a 20% lower risk of death from all causes and a 25% lower risk of dying from cardiovascular disease.

The new analysis included 12 studies published through February 2016 and unpublished results from the National Health and Nutrition Examination Survey, involving 786,076 men and women. Researchers reported that for about every serving (16 grams) of whole grains there was a:

– 7% lower risk of total deaths;

– 9% lower risk of cardiovascular disease-related deaths; and

– 5% lower risk of cancer-related deaths.

The more whole grains consumed, the lower the death rate. When three servings (48 grams) were consumed daily the risks were lower by:

– 20% for total deaths;

– 25% for cardiovascular deaths; and

– 14% for cancer-related deaths.

“Previous studies have suggested an association [between] consumption of whole grains and reduced risk of developing a multitude of chronic diseases that are among the top causes of deaths, although data linking whole grain intake and mortality were less consistent,” says Harvard scientist Qi Sun, MD, ScD, senior author of the study. “Based on the solid evidence from this meta-analysis and numerous previous studies that collectively document beneficial effects of whole grains, I think healthcare providers should unanimously recommend whole grain consumption to the general population as well as to patients with certain diseases to help achieve better health and perhaps reduce death.”

EAT WHOLE GRAIN TO LOWER RISK OF CHRONIC DISEASES:

Literally the next day, another large study was published in The BMJ reporting a strong association between greater whole grain consumption and lower risk of chronic diseases. In addition to looking at deaths in 45 prior studies totaling more than 700,000 participants, researchers also analyzed incidences of coronary heart and cardiovascular disease and stroke.

Consuming 90 grams a day of whole grains (five to six servings) was associated with a 17% lower risk of mortality from all causes and specific lower risk of death from cancer (15%), respiratory disease (22%), diabetes (51%) and infectious diseases (26%). People eating that level of whole grains were also at lower risk of coronary heart disease (19%), cardiovascular disease (22%) and stroke (14%), with similar lower risk of deaths from those causes.

Even a modestly higher intake of one or two servings a day was associated with benefits for those eating little or no whole grains. On the other hand, health benefits continued to increase with greater consumption.

Dagfinn Aune of Imperial College London and colleagues concluded, “Whole grain intake can be modified relatively easily by replacing refined grains and could have a large effect on the burden of chronic disease if adopted in the general population.”

EAT WHOLE GRAIN FOR HEART HEALTH:

Still other recent studies have added to the mounting evidence for whole grains. Chinese researchers, publishing their findings in the American Journal of Clinical Nutrition, analyzed 33 studies totaling more than 165,000 deaths. For every additional 50 grams of whole grains, they found 18%-30% lower mortality rates; the greatest benefit was associated with cardiovascular mortality.

A new Danish study of nearly 55,000 men and women, also published in the American Journal of Clinical Nutrition, found that those consuming the most whole grains were 23%-25% less likely to suffer a heart attack than those with the lowest intake. When specific grains were analyzed, oats and rye (whole grains less common in the US) were most strongly linked to lower heart-attack risk.

Convinced to start substituting more whole grains into your meals? Once you make whole grains a habit, it’s easy to the majority of your grains whole grains. Enjoying the natural nutrition of whole grains can add variety to your diet, help you avoid chronic disease and live better, longer.

TO LEARN MORE: Circulation, June 13 –

TO LEARN MORE: BMJ, June 14 –

TO LEARN MORE: American Journal of Clinical Nutrition, July 2016 –

TO LEARN MORE: American Journal of Clinical Nutrition, April 2016 –