The Nutritional Benefits of Wholegrains
June 25, 2015
For a food to be described as wholegrain it should contain all the essential parts and naturally-occurring nutrients of the entire grain seed.
The goodness of grains comes from all three layers: bran, endosperm and germ.
Bran is the tough, fibrous outer layer that protects the inside of the kernel. The next layer is the starchy endosperm, a storehouse of energy for the germ inside the endosperm. As the seed’s reproductive kernel, the germ contains vitamins, minerals, and unsaturated oils.
A cup of whole grains delivers about 10% of our daily protein requirements.
For vegetarians and vegans, combining whole grains with legumes and seeds will provide a complete source of protein.
As well as being a source for essential vitamins such as thiamine (B1), niacin (B3) pyroxidine (B6), and vitamin E, wheat, barley, buckwheat, millet, rye, and brown rice are good sources of minerals such as magnesium, phosphorus, manganese, copper and selenium. Oats also include iron and zinc in the package, while quinoa and mung beans supply folic acid.
Whole-grains and whole-legumes have a high content of dietary fibre which, along with adequate daily intake of water (make sure it’s filtered), assists with problems such as constipation.
Studies also suggest that the phytophenols in whole-grain fibre may protect against digestive cancers (1).
A recent meta-analysis indicated that high intake of whole grains is associated with reduced risk for type 2 diabetes (2).
And eating more whole grains has also been shown to protect against heart disease (3).
Overly refined grains have lost more than half their B vitamins, 90 percent of the vitamin E, and virtually all of the fibre.
This makes the starch easily accessible to our body’s starch-digesting enzymes, spiking blood sugar and creating that sugar high, then the ‘crash and burn’ after-effect.
Overall, the evidence suggests that whole grains are an entire nutritional package,
and when the elements are intact they work together.
To maximise nutrition and minimise processing it also makes sense to choose organic whole grains.
Sustainable organic farming focuses on nutrient rich soils so that the plant can extract the maximum nutrients and minerals during the growing season. In addition organic grains have not been treated with herbicides and pesticides on the farm, or while being stored at the mill.
Be wary of ‘wholemeal’ products, which may appear healthy.
Organic grains, even the white flours, usually undergo much less processing than conventional grains.
Conventionally milled wheat often has the bran layer removed (to make white flour), and then added back to create ‘wholemeal’ flour. Bread made with this flour can spike blood sugar as much as refined white flours.4 So look for products that are genuinely wholegrain.
If you eat cereals or toast for breakfast choose whole grains such as rolled oats or quinoa flakes to avoid a mid-morning energy slump. Try adding some seeds and nuts for that extra sustained release of energy.
If you do like white bread, then go for sourdough.
In one study researchers noticed that sourdough outperformed conventionally baked breads in different measures of glycemic and metabolic response. It seems that fermentation changes the nature of the starches in the grain, slowing our digestion process for a sustained release of the sugars in the starch (5). It’s now well known that blood sugar spikes lead to many long-term health issues that can be avoided. It may be the main reason whole grains are so good for us.
1. “Bound phytophenols from ready-to-eat cereals: Comparison with other plant-based foods”, Food Chemistry. 2013 Dec 1; 141(3):2880-6. (Neacsu et al.) http://www.sciencedirect.com/science/article/pii/S0308814613006067
2. “Whole grain and refined grain consumption and the risk of type 2 diabetes”; European Journal of Epidemiology. 2013 Nov; 28(11):845-58. (Aune et al.) http://www.ncbi.nlm.nih.gov/pubmed/24158434
3. “Whole-grain consumption and risk of coronary heart disease: results from the Nurses’ Health Study1,2,3,” American Journal of Clinical Nutrition, September 1999 vol. 70 no. 3 412-419; http://ajcn.nutrition.org/content/70/3/412.short
4. “Sourdough Bread Has Most Health Benefits, Prof Finds”; July 07, 2008 – News Release. http://www.uoguelph.ca/news/2008/07/sourdough_bread.html
5. Ibid. Also: Journal of Nutrition and Metabolism. 2012; 2012:184710. Mofidi et al. http://www.ncbi.nlm.nih.gov/pubmed/22474577
This article first appeared in Healthy You Magazine, Winter 2014 issue.
Written by Sheridan Kennedy on June 25, 2015