Cereal grains and coronary heart disease

Abstract

Cereal grains and their products provide around 30% of total energy intake in British adults, (much more than any of the other major food groups). Coronary heart disease (CHD) is the largest single cause of death in Britain and many other Western countries. This review examines the question whether there is a relation between cereal consumption and CHD.Several of the nutrients in cereals have known potential for reducing risk factors for CHD: the linoleic acid, fibre, vitamin E, selenium and folate. Cereals also contain phytoestrogens of the lignan family and several phenolic acids with antioxidant properties. Processing generally reduces the content of these nutrients and bioprotective substances. Although cereals at the farm gate are very low in salt, processed cereal foods, eg bread and some breakfast cereals, are high-salt foods and thus could contribute to raising blood pressure.Human experiments have clearly shown that oat fibre tends to lower plasma total and LDL cholesterol but wheat fibre does not. Rice bran and barley may also lower cholesterol but most people do not eat enough barley to have an effect. Cereal foods with low glycaemic index such as pasta and oats are beneficial for people with diabetes and might lower plasma lipids.Between 1996 and 2001 an accumulation of five very large cohort studies in the USA, Finland and Norway have all reported that subjects consuming relatively large amounts of whole grain cereals have significantly lower rates of CHD. This confirms an earlier report from a small British cohort. The protective effect does not seem to be due to cholesterol-lowering. While cohort studies have shown this consistent protective effect of whole grain cereals, there has been (only one) randomised controlled secondary prevention trial of advice to eat more cereal fibre. In this there was no reduction of the rate of reinfarction. The trial had some weaknesses, eg there were eight different diets, compliance was not checked objectively, and duration was for only 2 y.It appears valid to make health claims (as now permitted by the US FDA) that whole grain cereal foods and oat meal or bran may reduce the risk of CHD.

Cereal grains, legumes and diabetes

“…Whole grain foods have been clearly shown to be associated with a reduced risk of ischaemic heart disease (Truswell, 2002). Part of the favourable effect may be due to lowering of lipoprotein-mediated risk, notably a reduction in plasma total cholesterol and/or LDL cholesterol and triglycerides (Järvi et al, 1999;Chandalia et al, 2000).…”

Healthy Eating Index and C-reactive protein concentration: findings from the National Health and Nutrition Examination Survey III, 1988–1994

“…Our results suggest the possibility that some of this benefit may have occurred through a reduction in inflammation. The findings with respect to grain consumption are particularly intriguing because of accumulating evidence of the benefits of grain consumption, particularly whole grains, in reducing risk for chronic disease, particularly cardiovascular disease (Hu and Willett, 2002;Truswell, 2002;Liu, 2002). The mechanisms through which grain consumption might reduce inflammation are unclear.…”

Cereal based functional food of Indian subcontinent: a review

“…Also, cereals can be used as fermentable substances for the growth of probiotic microorganisms (Charalampopoulos et al 2002). Wheat, buckwheat, oat, barley, flaxseed, psyllium, brown rice and soy products are notified as the most common cereal based functional food and nutraceuticals (Truswell 2002). Cereals are used world-wide as staple foods.…”