by Jeff Novick, M.S., R.D., L.D./N.
Now, once again, another study shows that when it comes to healthy eating, whole foods are more important than isolated nutrients. In the study, women who ate a lot of whole-grain foods significantly reduced their risk of strokes. Those who ate the most were 30 percent to 40 percent less likely to have an ischemic stroke than women who ate less than half a serving daily. These findings are based on data on the 75,521 who participated in Harvard University’s Nurses Health Study, and appear in the October Journal of the American Medical Association (JAMA. 2000; 284: 1534-1540).
Strokes are the nation’s third leading cause of death and affect men and women equally but are more likely to be fatal in women. From 1984 to 1996, 352 strokes occurred in the study group. Most were ischemic strokes, caused by blockages in brain-feeding arteries. Most of the estimated 600,000 strokes reported each year nationwide are this type. In the study, the more whole grains women ate, the less likely they were to have a stroke.
The findings suggest that “replacing refined grains with whole grains by even one serving a day may have significant benefits in reducing the risk of ischemic stroke,” wrote the authors, led by Dr. Simin Liu of Harvard’s Brigham and Women’s Hospital in Boston. Whole grains consumed by study participants included whole-grain cereal, oatmeal, bulgur, couscous and even popcorn. Refined-grain foods included rolls, white bread, white rice and English muffins.
Liu said it is unclear exactly how whole grains might prevent strokes, although they have been linked to lower levels of the so-called bad cholesterol that can clog arteries. His study sought to determine what specific components of whole grains (such as vitamin E and fiber) might be responsible, but instead, he found a risk reduction independent of those factors, suggesting that other mechanisms are at work.
Many studies have shown that populations that live on a low fat, high complex carbohydrate, high fiber diet have better health than those who live on a high fat, low-carb, low-fiber diet. They have less heart disease, diabetes, hypertension, obesity, certain cancers and lower mortality. The high fiber complex carbohydrates that these healthier populations live on are whole grains like oats, corn, rice, millet, barley, potatoes and yams.
In the last 20 years, many Americans have tried to improve their health by switching to a low-fat, high-carb diet. However, in doing so, they have turned to refined and processed carbohydrates like breads, bagels, pasta, crackers, muffins, cookies and even refined sugar instead of whole grains. Indeed, according to US Department of Agriculture data, whole grains account for only 1% of total energy consumed by Americans today, while refined grains account for more than 20%.
Refined and processed grains are not the same foods as the whole grains that the healthier populations around the world live on. Refined and processed grains have less fiber, less vitamins, minerals, antioxidants, phytochemicals and less essential fatty acids. Refined and processed grains have 3-4 times the calorie density of whole grains, so they are less filling and it is therefore much easier to overeat on them.
For example, 1/2 cup of whole grain oatmeal has about 75 calories and is very filling. The same 1/2 cup of Grape Nuts cereal has over 200 calories and is less filling. As you can see, it is much easier to overeat on Grape Nuts.
A study in the American Journal of Public Health (1999; 89:322-329) showed the impact that even eating just one serving of whole grains a day could have on your health. They found that eating just one serving of whole grains per day reduces the risk of dying from cancer, cardiovascular disease and other chronic illnesses. Out of 38,740 women, aged 55 to 69, who were part of the Iowa Women’s Health Study, “women with higher intakes (of whole grain) had healthier lifestyles and less...disease,” wrote Dr. David R. Jacobs and colleagues from the University of Minnesota in Minneapolis.
Through the use of questionnaires, researchers determined that whole grain intake amongst the women studied varied from less than 1 to more than 3 servings per day. “During 9 years of follow-up... (the) women in this study who reported eating at least 1 serving per day of whole grain foods... had a substantially lower risk of mortality, including mortality from cancer, cardiovascular disease, and other causes, than did the women who reported eating almost no whole grain products,” according to the report.
“Amid substantial attention to the health effects of saturated fat and cholesterol, little public attention has been drawn to the importance of whole versus refined grains.” The researchers estimate that daily consumption of whole grain foods reduced mortality by about 15%. This finding held true even after the researchers accounted for differences in other factors that influence heart disease risk, such as fruit and vegetable consumption and body mass. None of this is surprising though; the nutrients and fiber missing from re-fined grains are thought to benefit heart health.
Adding just one serving a day of whole grains could result in better health. The researchers suggest that, “if all women consumed at least 1 serving per day of whole grain foods, total mortality rates might be reduced, through a variety of mechanisms, by 8% or more.”
Diets that are high in unrefined plant foods have consistently been linked with lower risks of certain diseases (like cancer, stroke and heart disease), though no one has been able to pinpoint a single protective compound. Again, this is because the action of any number of the thousands of phytochemicals found in plant foods — and not one single vitamin — is likely be-hind the benefits of whole foods. This is also why eating a diet high in refined processed foods, and/or relying on supplements of isolated nutrients can never work. You can’t get optimal nutrition from either one.
So, if you have been filling up on breads, bagels, pasta, crackers, cookies and other low fat, high carbohydrate, low fiber foods, thinking that these foods are healthy for you, it may be time for a change. Time to start replacing refined and processed grains with whole grains.
How to do it?
To improve your health, include more whole grains in your diet each day. Even starting out by adding at least one serving a day can make a big difference.
Have oatmeal or another hot whole grain cereal for breakfast.
Have some brown rice with your lunch or dinner.
Snack on an ear of corn or include some corn with a meal.
Add some barley to your favorite soup or stew recipe.
Try some of the varieties of whole grains that you may not be familiar with like buckwheat (kasha), millet, rye, quinoa or spelt.
©Copyright 2001. All Rights Reserved. Health Science is the publication of the National Health Association. This article reprinted from the Summer 2001 issue.