Probably the single most effortless action you can do to increase longevity, reduce the risk of all causes of mortality (Dagfinn, et al, 2016) and improve the quality of your life, is the switch from refined grains to whole grains, because the consumption of whole grains, provide vital nutrients that contribute to the health and maintenance of the human body.(Bae et al, 2013)
Whole grains vs Refined grains
The difference between refined and whole grains is that the whole grain contains the seed and all its key parts: bran, germ, endosperm. Refined grains have their germ and bran removed. Examples of whole grains include whole wheat, dark bread, brown rice, oats, barley and rye.
These seed parts contain main vital nutrients which are of course lost, once removed.
- Protein (22% loss)
- Vitamin E (92 % loss)
- Vitamin B6 (89% loss)
- Vitamin K (84% loss)
- Magnesium (84% loss)
- Thiamin (B1) (76% loss)
- Riboflavin (B2) (76% loss)
- Niacin (B3) (75% loss)
- Fibre (75% loss)
- Potassium (71% loss)
- Iron (67% loss)
- Calcium (56% loss)
- Selenium (45% loss)
- Folate (41% loss)
(Source: Whole grain Council)
Several other nutrients are lost as well. Trace minerals, fibre and phytochemicals such as polyphenolics.
Enriched refined grains
To reduce the loss, some countries require certain refined grains to have some of the lost nutrients added back. Those nutrients are:
- Thiamin (B1)
- Riboflavin (B2)
- Niacin (B3)
The product is then called enriched (example enriched wheat flour) but just like in the regular refined grains, the rest are lost for good, along with their health promoting properties.
Phytochemicals and fiber
- As much as 75% of phytochemicals (phytonutrients) are lost in the refining process. (Minnesota department of health, n.d.) This high percentage includes polyphenols. A chemical that neutralizes n-nitrosamines protects that cause oxidative DNA damage. Among with Vitamin E (which is lost by 92% during the refining process), It offers antioxidant properties. The minerals contained in whole grains are needed by enzymes that conduct antioxidant functions (such as glutathione peroxidase, superoxide dismutase). that are of course lost during the refining process.
- The fiber in whole grains lowers the serum glucose and insulin hence reduces the risk of diabetes 2. Another function of the fiber is to absorb the cholesterol and increase its excretion. This leads to lowering the risk of cardiovascular disease. In addition, fiber reduces inflammation and it is beneficial for the bacteria living in the gut, which then releases substances that promote lower levels of inflammation in the body. (Arthritis Foundation, n.d). On top of that, Aune et al (2011) suggest that a high intake of dietary fiber, in particular, cereal fiber and whole grains, reduces the risk of colorectal cancer.
How much whole grain to eat?
Whole grain’s health effects are countless. Their benefits are confirmed by a plethora of journals. But how much is enough to achieve all these desirable results? The “Dietary guidelines for Americans” recommend the consumption of 3 to 5 servings of whole grains a day.
One serving of whole grains is equal to:
- 1 slice of 100% whole grain bread
- ½ cup cooked 100% whole wheat pasta, brown rice, quinoa, or oatmeal (1 ounce dry)
- 5 small whole wheat crackers
- 2 rye crispbread
- 1 small 100% whole wheat flour tortilla or corn tortilla (6” diameter)
- 3 cups of popped popcorn
- 1 cup cold whole grain cereal flakes
(source: Minnesotan department of health)
In other words, a daily consumption of only 3 slices of 100% whole grain bread will provide you all of the benefits discussed so far, plus a:
- Reduced risk of type 2 diabetes by 26% (Ye, et.al, 2012)
- Reduced incidence of cardiovascular disease by 21% (compared to those consumed 0,2 servings day).(Mellen, et.al, 2008)
- Reduced risk of breast cancer. (Mourouti, et al, 2016)
- Reduced risk of pancreatic cancer (lei, et al, 2016)
- Reduced risk of hypertension in middle-aged and older women (Wang, et al 2007)
- Reduced risk of colon cancer (Larsson et al 2011)
Whole grains as a culinary choice
Despite the fact that whole grains are healthier compared to refined grains and their prices are comparable, they are not a widely accepted in personal and commercial culinary choice.
A recent study seems to have pinpointed the reason. The study concluded that whole grains reduce the quality and sensory value in food products because the high concentration of fiber has a negative effect on food texture. If a food product has elevated amounts of fiber, alternative products must be used to improve or maintain the quality.
The study suggests the golden rule of whole grain and refined flour should be 50% – 50% because it results in both acceptable palatable qualities and beneficial health effects. (Bae, et al. 2013)
References and Bibliography:
Aune, D., Chan, D. S. M., Lau, R., Vieira, R., Greenwood, D. C., Kampman, E. and Norat, T. (2011) ‘Dietary fibre, whole grains, and risk of colorectal cancer: systematic review and dose-response meta-analysis of prospective studies.’, BMJ (Clinical research ed.), 343, p. d6617. Available at: http://www.ncbi.nlm.nih.gov/pubmed/22074852 (Accessed: 27 February 2017).
Bae, I. Y., Lee, H. I., Ko, A. and Lee, H. G. (2013) ‘Substituting whole grain flour for wheat flour: Impact on cake quality and glycemic index’, Food Science and Biotechnology, 22(5), pp. 1–7. doi: 10.1007/s10068-013-0216-4.
Fiber and Inflammation [WWW Document], n.d. URL http://www.arthritis.org/living-with-arthritis/arthritis-diet/anti-inflammatory/fiber-inflammation.php (accessed 2.20.17).
Larsson, S. C., Giovannucci, E., Bergkvist, L. and Wolk, A. (2005) ‘Whole grain consumption and risk of colorectal cancer: a population-based cohort of 60 000 women’, British Journal of Cancer, 92(9), pp. 1803–1807. doi: 10.1038/sj.bjc.6602543.
Lei, Q., Zheng, H., Bi, J., Wang, X., Jiang, T., Gao, X., Tian, F., Xu, M., Wu, C., Zhang, L., Li, N. and Li, J. (2016) ‘Whole Grain Intake Reduces Pancreatic Cancer Risk: A Meta-Analysis of Observational Studies.’, Medicine. Wolters Kluwer Health, 95(9), p. e2747. doi: 10.1097/MD.0000000000002747.
Mattoo, a., shukla, V., Fatima, T., handa, A. &Yachha, S. (2010) genetic engineering to enhance crop- based phytonutrients (nutraceuticals) to alleviate diet-related diseases. Advances in experimental medicine and biology, 698, 122-143
Mayo Clinic Health (2014) ‘Whole grains: hearty options for a healthy diet’, Mayo clinic, pp. 13–15. Available at: http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/whole-grains/art-20047826 (Accessed: 15 February 2017).
Mellen, P. B., Walsh, T. F. and Herrington, D. M. (2008) ‘Whole grain intake and cardiovascular disease: A meta-analysis’, Nutrition, Metabolism and Cardiovascular Diseases, 18(4), pp. 283–290. doi: 10.1016/j.numecd.2006.12.008.
Mourouti, N., Kontogianni, M.D., Papavagelis, C., Psaltopoulou, T., Kapetanstrataki, M.G., Plytzanopoulou, P., Vassilakou, T., Malamos, N., Linos, A., Panagiotakos, D.B., 2016. Whole Grain Consumption and Breast Cancer: A Case-Control Study in Women. Journal of the American College of Nutrition 35, 143–149. doi:10.1080/07315724.2014.963899
The Whole Grains Council (2013) The main benefits of whole grains. Available at: http://wholegrainscouncil.org/ (Accessed: 15 February 2017).
Vitaglione, P., Mennella, I., Ferracane, R., Rivellese, A.A., Giacco, R., Ercolini, D., Gibbons, S.M., La Storia, A., Gilbert, J.A., Jonnalagadda, S., Thielecke, F., Gallo, M.A., Scalfi, L., Fogliano, V., 2015. Whole-grain wheat consumption reduces inflammation in a randomized controlled trial on overweight and obese subjects with unhealthy dietary and lifestyle behaviors: role of polyphenols bound to cereal dietary fiber. The American Journal of Clinical Nutrition 101, 251–261. doi:10.3945/ajcn.114.088120
Wang, L., Gaziano, J. M., Liu, S., Manson, J. E., Buring, J. E. and Sesso, H. D. (2007) ‘Whole- and refined-grain intakes and the risk of hypertension in women.’, The American journal of clinical nutrition, 86(2), pp. 472–9. Available at: http://www.ncbi.nlm.nih.gov/pubmed/17684221 (Accessed: 27 February 2017).
Ye, E. Q., Chacko, S. A., Chou, E. L., Kugizaki, M. and Liu, S. (2012) ‘Greater Whole-Grain Intake Is Associated with Lower Risk of Type 2 Diabetes, Cardiovascular Disease, and Weight Gain’, Journal of Nutrition, 142(7), pp. 1304–1313. doi: 10.3945/jn.111.155325.