Medical research shows walnut health effects
Published on 23 November 2015 in Volume 3, Issue 1 of the free online journal called ‘BMJ Open Diabetes Research Care’, which is published by the British Medical Journal, the research in the article found that incorporating walnuts as part of an individual’s daily diet improved blood vessel cell wall function and lowered ‘bad’ cholesterol levels after six months.
The researchers randomly assigned 112 people to either following a diet with dietary counselling designed to curb calorie intake, or one without. Within these two groupings, participants were randomly assigned to the daily inclusion of 56 g (2 oz) of walnuts in their diet or the complete avoidance of walnuts for a period of six months.
After a three month interlude, the intervention arms were reversed.
The 31 men and 81 women, who were aged between 25 and 75, were all at high risk of developing diabetes.
Their height, weight, BMI, waist circumference, blood pressure, cholesterol, fasting blood glucose, and HbA1c (glycated haemoglobin), which gives an indication of average blood glucose levels over time, were assessed at the start of the trial, and then again after 3, 6, 12 and 15 months. Dietary intake was similarly assessed at these time points. Diet quality was assessed using the Healthy Eating Index 2010 (HEI-2010). Improved diet is associated with a better cardiovascular risk profile and a lowered risk of long term conditions.
After taking account of influential factors, such as age, calorie and fatty acid intakes, and the amount of regular exercise taken, the analysis indicated that adding walnuts to the daily diet was associated with improved diet quality.
“Our data suggest that inclusion of walnuts in diet, with or without dietary counselling to adjust caloric intake, improved diet quality and may also improve [endothelial function], and reduce total and LDL cholesterol in this sample of adults at risk for diabetes,” the researchers concluded.
Walnuts are already known to contain essential fatty acid and other nutrients such as folate and vitamin E. Scientists however say serving sizes must be controlled as the nuts are high in calories. The scientists also say further studies in more diverse groups of people are warranted.