Anti-Inflammatory Properties of Walnuts also reduced Heart Disease Risk

Study "Effects of 2-Year Walnut-Supplemented Diet on Inflammatory Biomarkers" reported in the Journal of the American College of Cardiology suggest that people who regularly eat walnuts in their 60s and 70s may have decreased inflammation, a factor associated with a lower risk of heart disease, relative to those who do not eat walnuts. The study was part of the study on Walnuts and Safe Aging (WAHA), the largest and longest trial to date investigating the benefits of daily consumption of walnuts.

          

"Robust epidemiological evidence shows that daily intake of nuts is associated with a lower risk of cardiovascular disease ( CVD). When comparing extreme amounts of total nut intake (2.5 to 28 g / day), total CVD and CVD mortality were 15 percent and 23 percent lower, respectively, as summarised in a recent meta-analysis of 19 prospective studies. In 3 studies, walnut consumption independent of other nuts showed similar inverse associations with CVD, "the investigators report."

Since nuts have a consistent cholesterol-lowering effect, nut consumption may be associated with a lower CVD risk. A meta-analysis of 24 randomised controlled trials ( RCTs) concluded that walnut-enriched diets resulted in substantial weighted mean differences in low-density lipoprotein cholesterol (-5.5 mg / dl) relative to control diets, but did not affect blood pressure or C-reactive high-sensitivity protein (hs-CRP). With weighted mean differences in flow-mediated dilatation of 0.79 percent in 8 RCTs, nut-enriched diets also affect endothelial function. However, the lower CVD results found in prospective studies can not completely account for these moderate salutary effects of nut diets. Given the prevailing theory that inflammation is a major driver of atherosclerosis, one possible mechanism that links nut consumption to decreased CVD may decrease inflammation.

We hypothesised that it will boost inflammatory biomarkers by introducing walnuts into the regular diet. Therefore, in the WAHA (Walnuts And Healthy Aging; NCT01634841) study, a dual-center (Hospital Clínic, Barcelona, Spain, and Loma Linda University, Loma Linda, California) RCT designed to evaluate walnut effects on age-related health outcomes in 708 healthy elders (63 to 79 years of age), changes in circulating inflammatory molecules were evaluated. Cognitive function, the primary outcome, was impaired by walnut intake only in the high-risk subgroup. A pre-specified secondary outcome was improvements in inflammatory markers.

More than 600 stable older adults ate 30 to 60 grammes of walnuts per day as part of their typical diet or adopted their normal diet (without walnuts) for two years in the research, conducted by Emilio Ros, MD , PhD, from the Hospital Clinic of Barcelona, in collaboration with Loma Linda University. There was a substantial reduction in inflammation among those who ate walnuts, measured by the concentration of recognised inflammatory markers in the blood, which was reduced by up to 11.5 percent. Six of the 10 well-known inflammatory markers measured in the study were significantly reduced in the walnut diet, including interleukin-1β, a potent pro-inflammatory cytokine that has been closely associated with decreased rates of coronary heart disease due to pharmacological inactivation. The study's conclusion is that walnuts' anti-inflammatory effects offer a mechanistic basis for reducing cardiovascular disease beyond lowering cholesterol.

Acute inflammation is a physiological process triggered by injury such as trauma or infection to stimulate the immune system and is an effective protection of the body, says Ros, a lead researcher in the study. Short-term inflammation helps us heal wounds and combat infections, but inflammation caused by factors such as poor diet, obesity, stress and high blood pressure that persists overtime (chronic) is harmful instead of healing, particularly when it comes to cardiovascular health.' The results of this research indicate that walnuts are one food that can minimise chronic inflammation, which can help reduce the risk of heart disease , a condition to which we become more susceptible as we age.

Although current scientific evidence recognises walnuts as a heart-healthy food, researchers continue to study the "how" and "why" behind the cardiovascular benefits of walnuts. Walnuts have an perfect combination of vital nutrients such as omega-3 alpha-linolenic acid or ALA (2.5g / oz) and other highly bioactive components such as polyphenols, which are likely to play a role in their anti-inflammatory and other health benefits, according to Ros.