Repeated studies have linked higher whole grain intakes to protection against heart disease, stroke, type 2 diabetes and obesity.nehopelon/iStockPhoto / Getty Images
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If you don’t eat whole grain foods on a daily basis, consider rethinking your menu.
According to researchers from Tufts University in Boston, doing so can help you manage your waist size, blood sugar (glucose) and blood pressure as you age. And it doesn’t take a lot. The sweet spot, it seems, is three whole grain servings each day.
Repeated studies have linked higher whole grain intakes to protection against heart disease, stroke, type 2 diabetes and obesity.
The latest findings, published earlier this month in the Journal of Nutrition, suggest that whole grains guard against chronic disease by reducing increases in risk factors that occur over time.
What are whole grains?
All grains – such as wheat, rye, barley, spelt, oats – start out as whole grain kernels made up of three layers: The outer bran layer, which contains nearly all the fibre; the inner germ layer, which is rich in nutrients, antioxidants and healthy fats; and the starchy endosperm.
Eating whole grains and 100-per-cent whole grain foods means that you’re getting all parts of the grain kernel.
When whole grains are processed into refined flour, the bran and germ layers are removed, resulting in a loss of most of the fibre, one-quarter of the grain’s protein and a substantial amount of at least 17 nutrients.
About the new study
The researchers compared how whole grain and refined grain intake affected changes in five risk factors for heart disease and stroke: waist circumference, fasting blood glucose, blood pressure, blood triglycerides (fats) and HDL (“good”) blood cholesterol.
They did so by assessing the diets and health of 3,121 middle-aged and older adults, every four years, over a span of 18 years. Participants were, on average, 55 years old at the start of data collection.
People who ate at least three daily servings of whole grains (versus one-half or less) experienced smaller increases in waist circumference. Over each four-year period, waist circumference increased one inch among those who ate few whole grains compared to one-half inch among those who ate more whole grains. The protective effect of whole grains on waist size was strongest in women.
Whole grain eaters also had smaller increases in fasting blood glucose and blood pressure over time.
With respect to refined grains (such as white bread, white pasta and white rice), the results revealed that people who ate four or more servings per day (versus fewer than two) experienced greater increases in waist circumference and smaller declines in blood triglycerides over the study period.
Benefits of whole grains
Eating fibre-rich whole grains can help you feel satiated and prevent overeating. The soluble fibre in whole grains can also help prevent spikes in blood sugar and insulin after eating. This may, in turn, favour fat-burning rather than fat storage.
Whole grains are also good sources of magnesium and potassium, minerals used to regulate blood sugar and blood pressure. And many whole grains contain prebiotic carbohydrates, which fuel beneficial gut microbes.
How to increase your whole-grain intake
One serving of whole grain is equivalent to one slice of 100-per-cent whole grain bread or one-half cup of cooked whole grain pasta or cooked whole grain (including oats, brown rice, farro, millet and hulled barley).
Read labels on packages of whole grain breads, crackers and breakfast cereals. If you don’t see “100-per-cent whole grain” listed, scan the ingredient list to make sure the product doesn’t contain refined grains (for example, wheat flour).
When buying rye bread look for ingredients that indicate whole grain such as whole rye flour, rye meal, rye kernels and rye flakes.
Don’t be fooled by claims of added fibre. Wonder White + Fibre bread, for example, isn’t a whole grain bread. Nor is Catelli’s Smart Pasta. Both are refined grain products with added oat hull fibre (and inulin in the pasta).
If you avoid wheat, rye and barley because they contain gluten, include gluten-free whole grains in your daily diet such as brown rice, quinoa, millet, teff, sorghum, buckwheat, amaranth and gluten-free oats.
Batch cook whole grains so that you have them ready to add to meals. Toss cooked quinoa, bulgur or farro into green salads; add barley, red rice or spelt berries to soups, stews and chilis; or make whole grain bowls with freekeh or brown rice.
Leslie Beck, a Toronto-based private practice dietitian, is director of food and nutrition at Medcan. Follow her on Twitter @LeslieBeckRD