While nuts such as almonds, walnuts, Brazil nuts, hazelnut and macadamia are rich in oil content, they are also ideal sources of nutrients. Several studies have reported that people who consumed nuts regularly were less likely to suffer from heart disease and stroke. There were many other researches linking consumption of nuts to lower bad cholesterol (low-density lipoprotein or LDL), too.
On September 12, 2011, researchers from the University of Barcelona and the Human Nutrition Unit of the Rovira i Virgili University found the association between eating nuts and higher levels of serotonin in the bodies of patients with metabolic syndrome. Their findings can be found in the American Chemical Society’s (ACS) ‘Journal of Proteome Research’.
Serotonin, which helps transmit nerve signals and lower feelings of hunger, makes people feel happier and improves heart health. Only one ounce of mixed nuts (raw unpeeled walnuts, almonds and hazelnuts) can produce good effects.
According to researchers, the increased rate of obesity around the world indicates that more people have metabolic syndromes. As estimated by the World Health Organization (WTO), metabolic syndrome affects 20 percent of the adult population. In the United States, the prevalence of metabolic syndrome is close to 25 percent in adults.
Symptoms of metabolic syndrome include excess abdominal fat, high blood sugar and high blood pressure, which in turn raise the risk of developing Type-2 diabetes and heart disease. Health experts believe changes in diet might help patients reduce excess weight. Among the changes, regular consumption of nuts has been recommended to fight the metabolic abnormalities associated with metabolic syndrome.
The study looked at 22 people with metabolic syndrome who were given a nut-enriched diet for 12 weeks. The researchers compared them to another group of 20 people who were told to avoid nuts.
After analyzing the broad spectrum of compounds excreted in the patients' urine, researchers found that consumption of nuts had boosted patients' levels of serotonin metabolites in urine and suggested the role of serotonin in the beneficial effects of nuts.
Researchers claimed that their study provided the first evidence in humans of the beneficial effects of nut consumption in reducing levels of substances in the body associated with inflammation and other cardiovascular risk factors in patients with metabolic syndrome.