Oats could hold the key to a healthier lifestyle
Published on 21 March 2011 in Food, health and wellbeing
Introduction
Cardiovascular disease (CVD) is the main cause of mortality in Western countries. Mortality rates from the condition in Scotland are amongst the highest in the world. The disease has multi-factorial causes of which dietary factors represent a key component.
The consumption of whole grain foods, such as wholemeal bread, wholemeal pasta or whole grain cereals (porridge, whole wheat) is associated with lowered risk of heart attack. Moreover, whole-grain food intake appears more strongly protective than intakes of fibre, vegetables or fruits. Whole grain intake has been associated with a reduced risk of type 2 diabetes and could also be effective in reducing blood cholesterol and hypertension, as well as other CVD risk factors.
In the UK, wholegrain foods are comprised mainly of wheat and oats. Oat-based foods contain high amounts of soluble fibres such as pectins, gums, and hemicelluloses whereas wheat-based foods contain high amounts of insoluble fibers (mainly cellulose and insoluble hemicelluloses). These differences in composition between both types of whole-grain food may be responsible for differential effects on blood cholesterol. Oats, and other foods containing high amount of soluble fibres seem more effective than wheat in reducing “bad” cholesterol in the blood.
Key Points
- High blood pressure is one of the most important risk factor for CVD, particularly stroke.
- Research has focused mainly on the effect of soluble fibres present in whole grain which can reduce blood cholesterol concentration.
- Current UK dietary advice regarding the consumption of whole grain foods is only contained within more general advice to increase the consumption of complex carbohydrates.
Research Undertaken
A large wholegrain intervention study (one of the largest of its type worldwide) commissioned by the Food Standard Agency under the Diet and Cardiovascular Health Research Programme, has recently been conducted at the Medical School and the Rowett Institute of Nutrition and Health at the University of Aberdeen.
We found that three daily portions of whole grain (wheat and/or oats), can significantly reduce blood pressure in middle aged overweight people. The decrease observed (5 to 6 mm Hg) could result in the decrease of coronary artery disease and stroke by 15% and 25%, respectively.
Interestingly, none of the other markers of disease risk, such as total and LDL cholesterol concentrations in blood were affected by the intervention. We are now trying to identify the components present in whole grain responsible for these effects as well as to understand the mechanisms by which wholegrain reduces blood pressure. This information will help to the development of novel strategies to prevent and/or treat cardiovascular disorders.
Policy Implications
Although the mechanisms by which whole grain foods decrease blood pressure remain unclear, our findings have important public health implications and provide a sound scientific basis for advising the daily consumption of 3 servings of whole grain foods to combat CVD.
Author
Dr Frank Thies f.thies@abdn.ac.uk
