Scientists at Pennsylvania State University in the USA, Penn State for short, were able to prove that walnuts improve intestinal health with the help of a study of 42 test persons aged between 30 and 65 years who were overweight and obese. The study participants were divided into three groups. Only one group received walnuts during the six weeks of study participation. But all of them received less saturated fat in their diet than two weeks before the diet when they were fed normal American food. The stool sample analysis after the three different diets showed that bacterial species such as Roseburia, which protects the intestinal mucosa, accumulated in the intestines of the walnut group. However, a connection between a healthy intestinal flora and a reduction of heart disease risks was also found. Walnuts contain many healthy vitamins and minerals, dietary fibres and secondary plant substances, and above all quantities of healthy alpha-linolenic acid (ALA), a polyunsaturated fatty acid. Researchers at the American university, therefore, recommend 55 to 85 grams of walnuts per day as a heart- and gut-healthy snack in exchange for unhealthy snacks that would otherwise be consumed. This is because walnuts primarily increase certain bacteria in the intestine, which leads to better intestinal health by improving the so-called intestinal microbiome. Small improvements in nutrition, the researchers conclude, have a major impact on human health. Walnuts, for example, also reduce blood pressure as a natural blood pressure reducer. But also values of total cholesterol and LDL cholesterol (low-density lipoprotein) as a bad component of blood fats can be lowered in a natural way. Soon, scientists at Penn State will be researching the effect of walnuts on blood sugar levels.
