Walnuts Reduce Cholesterol and Protect Against Heart Disease in Elderly

 

“It's encouraging to see that eating walnuts may benefit this particular population,” says Dr Emilio Ros, director of the Lipid Clinic, Endocrinology & Nutrition Service at the Hospital Clinic of Barcelona.

 

Just one-and-a-half ounces of the nuts, high in polyunsaturated fats (PUFAs), can boost friendly bacteria in the gut which reduce inflammation and cholesterol – both of which contribute to heart disease. They also reduce hunger and increased feeling full (satiety).

 

Every 28 grams (1oz) of walnuts contains 13 grams of PUFA, and they are the only nut with high levels of alpha-linolenic acid (ALA), the plant-based omega 3 fatty acid with 2.5 gram per ounce serving.

 

WAHA was a two-year clinical trial conducted by researchers from the Hospital Clinic of Barcelona and Loma Linda University aimed at determining the effect of walnuts on age-related health issues.

 

Dr Ros said: "Given walnuts are a high-energy food, a prevailing concern has been that their long term consumption might be associated with weight gain.”

 

"The preliminary results of the WAHA study demonstrate that daily consumption of walnuts for one year by a sizeable cohort of ageing free-living persons has no adverse effects on body weight.”

 

"They also show that the well-known cholesterol-lowering effect of walnut diets works equally well in the elderly and is maintained in the long term.”

 

"Acquiring the good fats and other nutrients from walnuts while keeping adiposity at bay and reducing blood cholesterol levels are important to overall nutritional well-being of ageing adults.”

 

The study followed 707 healthy older adults who added daily doses of walnuts which was equivalent to a sixth of caloric intake to their typical diet or to consume their usual diet without nuts.

 

After a year, the study found that both diets had minimal effect on body weight, triglycerides, and HDL cholesterol.

 

However, the walnut-diet resulted in significant LDL cholesterol reductions compared to the control, nut-free diet.

 

Dr Ros added: "As we continue the WAHA study, we will assess how walnut consumption may affect, among other outcomes, cognitive decline and age-related macular degeneration, conditions that were major public health concerns."

 

Other studies presented at Experimental Biology (EB) 2016 in San Diego suggested walnuts improved gut health, hunger and satiety, and metabolic health.

 

Researchers from the US's Agricultural Research Service found one-and-a-half ounces of walnuts a day significantly affected gut bacteria favorable to decrease inflammation and cholesterol, which are two known indicators of heart health.

 

A University of Georgia study found the types of fat eaten on a daily basis can alter long-term appetite responses, such as hunger and satiety.

 

After consuming high-fat meals rich in saturated fat, 18 sedentary adults of normal weight were randomly assigned to consume either a diet high in PUFA or a control diet for the next seven days.
The researchers found that those who ate a diet high in PUFA favorably alters hunger and satiety markers.

 

Finally, Oregon State University looked at the addition of walnuts and polyphenol-rich foods to a typical high-fat Western diet in mice. Results showed that a walnut-diet supplemented with polyphenol-rich foods such as raspberries, cherries or green tea may help reduce inflammation. Mice that consumed walnuts on their own or in combination with polyphenol-rich foods also demonstrated significant effects on factors related to metabolic syndrome, as well as liver gene expression.

 

Scientific conclusions cannot yet be drawn from abstracts presented at EB 2016, but these findings help advance the understanding of potential benefits of eating walnuts as part of a healthy diet.

 

All studies supported in part by the California Walnut Commission (CWC) were published in The Federation of American Societies for Experimental Biology (FASEB) Journal.