Nutrition
Health benefits of whole grains
Abstract
An analysis of many studies shows evidence of benefits for overall health, including reductions in vascular problems (eg stroke) and cancer.
We’ve always known whole grains are good. They even taste as though they are good for you, but we’ve been a bit hestitant to quantify just how good they are. In part, due to the difficulty in studying the relationship between diet and health. A recent study published in the British Medical Journal, has laid these ambiguities to rest, confirming that whole grains add signifcant value to our diet, leading to a reduction in heart disease, stroke and cancer as well as overall mortality.
They may not seem like it at first glance, but grains are a complex structure.
During the refining process, all of that complexity disappears as the germ and bran which are the good parts of the grain are removed. They contain vitamins, fiber and minerals such as iron, magnesium and zinc as well as antioxidants.
Whole grains are exactly as they sound - they include every component of the grain, both the nutrients in the outer shell and the germ. Refined grains contain only the ‘endosperm’ which is purely a source of carbohydrate. Choosing white bread over wholemeal bread essentially says no to any of these additional nutritents contained in the shell and germ of the grain.
Whole grains include brown rice, unrefined maize and sorghum, a well as whole grain bread and breakfast cereals. Many studies have suggested the benefits of whole grains, linking consumption to lower risk of heart disease and stroke, and overall mortality, yet recommendations within nutritional guidelines tend to be vague suggesting for example to ‘eat relatively unprocessed grains with every meal’ in the World Cancer research fund report.
A recently published meta-analysis; a study which combines the results of multiple, large scale trials, has pretty well set the consensus in stone, whole grains are good for you and may even lengthen your life.
The paper analysed the results of 45 studies looking at the relationship between grain intake and coronary heart disease, stroke, cardiovascular disease, total cancer and all-cause mortality.
It found that whole grain consumption lowered your risk of coronary artery disease by 21% when comparing groups with low intake to high intake. They also noted a strong dose-response trend, in which the more whole grains you ate, the lower your risk was.
It appeared that a high intake of whole grain bread, whole grain breakfast cereals and added bran seemed to have a significant impact in this reduction.
Similary with stroke, the study found a 13% lower risk of stroke in the high-intake group, however there was no further reduction in risk past a certain daily wholegrain intake (120-150 g a day) unlike coronary artery disease.
Similar risk reductions of 16% for cardiovascular disease and 11% risk decrease for total cancer were observed as well as total mortality being reduced by 18%.
Overall the lowest risk of illness was observed at whole grain intakes of 225g/day which equates to around 7 -7.5 servings a day.
Notebaly, there was no significant association between the intake of oats or oatmeal and mortality. Other less common causes of death were also analysed, with results finding that the risk of mortality from lung disease, diabetes and infection was lowered with higher intake of whole grains.
There really is no longer any doubt about it, wholegrains are good for, and in many cases the more you eat the better; the lower your risk. So next time you are in the bread or cereal aisle, think of your heart and choose that wholegrain pita pocket.
Reference:
Aune, Dagfinn et al. "Whole Grain Consumption And Risk Of Cardiovascular Disease, Cancer, And All Cause And Cause Specific Mortality: Systematic Review And Dose-Response Meta-Analysis Of Prospective Studies". BMJ (2016): i2716. Web. 30 June 2016.