Whole grains are nutrition powerhouses containing over 26 nutrients and bioactive substances including dietary fibres, vitamins, minerals, and a range of protective phytonutrients. Studies have shown that adults and children who consume higher intakes of whole grain foods each day have better diet quality and nutrient intakes(1, 2) including higher intakes of fibre, all vitamins and most minerals as well as lower intakes of added sugar and saturated fat.(1)
Overall, studies show that consuming 2-3 serves of whole grain foods each day reduces the risk of cardiovascular disease, type 2 diabetes, colon cancer and obesity by around 20-30%.(3, 4)
Interestingly the disease risk reduction which whole grains appear to offer far exceeds the protection expected from the individual nutrient found in whole grains.(5) As such, it is likely the beneficial nutrients and phytonutrients found in whole grains have individual, synergistic and additive actions that positively affect health.(6, 7)
Here is an outline of some of the many possible mechanisms by which whole grains reduce risk of disease(5):
- The actions and interactions of the many phytonutrients, including antioxidant compounds and polyphenols found in whole grains.
- The ‘prebiotic effect’ of whole grains which results in beneficial changes in the good bacteria which live in our gut.
- Beneficial pH changes in the colon.
- Through a positive influence on blood glucose control, particularly with low glycemic index (GI) whole grain foods including oats, rye, barley and quinoa based foods.
- Through the beneficial effects of the different types of dietary fibres which promote digestive regularity and digestive wellbeing.
For a guide to boost your whole grain intake, check out GLNC’s Fact Sheet Whole grain foods - A hallmark of a healthy diet.
References:
- O'Neil CE, Nicklas TA, Zanovec M, Cho S. Whole-grain consumption is associated with diet quality and nutrient intake in adults: the National Health and Nutrition Examination Survey, 1999-2004. Journal of the American Dietetic Association. 2010;110(10):1461-8.
- O'Neil CE, Nicklas TA, Zanovec M, Cho SS, Kleinman R. Consumption of whole grains is associated with improved diet quality and nutrient intake in children and adolescents: the National Health and Nutrition Examination Survey 1999-2004. Public health nutrition. 2011;14(2):347-55.
- NHMRC. A Modelling System to Inform the Revision of the Australian Guide to Healthy Eating. . Canberra Department of Health and Ageing, 2011.
- GLNC. The Grains & Legumes Health Report. Grains & Legumes Nutrition Council, 2010.
- Slavin J. Why whole grains are protective: biological mechanisms. The Proceedings of the Nutrition Society. 2003;62(1):129-34.
- Okarter N, Liu RH. Health Benefits of Whole Grain Phytochemicals. Critical reviews in food science and nutrition. 2010;50(3):193-208.
- Liu RH. Potential Synergy of Phytochemicals in Cancer Prevention: Mechanism of Action. The Journal of nutrition. 2004;134(12):3479S-85S.