Walnut is an edible seed of the tree nut Juglans regia. These nutrient contain high levels of polyphenols, phytochemicals that have antioxidant effects. Also, walnuts are an excellent source of a proteins, fiber, and manganese, magnesium and copper.
Researchers from Pennsylvania told the American Chemical Society that walnuts contain the highest amount of antioxidants compared to other nuts. Antioxidants protect cells against damage caused by harmful molecules known as free radicals. The researchers said that all nuts have good nutritional qualities but walnuts are healthier than peanuts, almonds, pistachios and pecans. Dr Joe Vinson, from the University of Scranton in Pennsylvania, tested the antioxidant levels of nine different types of nuts and discovered that a handful of walnuts contained twice as many antioxidants as a handful of any other commonly eaten nut. “Twenty-eight grams of walnuts have more antioxidants than the sum of what the average person gets from fruits and vegetables,” he says.
Nuts, like almonds, hazel nuts, Brazil nuts, peanuts, walnuts and cashews can all play a role in reducing the risk of heart disease, according to a Harvard review. Walnuts are a good source of the healthy fat alpha linolenic acid. (One-quarter cup of walnuts provides all the alpha linolenic acid you need in a day). New researches have associated a higher intake of alpha linolenic acid to a reduced risk of heart disease and heart attack in men. One study looked at nuts rich in alpha linolenic acid (ALA), like walnuts, and found that they had a heart-protective effect during times of acute stress. A meta-analysis reported in the new ssue of the “American Journal of Clinical Nutrition” evaluates how the plant-based omega-3 fatty acid ALA offers protective effects on cardiovascular diseases. The study found ALA to be linked with a lower risk of cardiovascular diseases, especially coronary heart disease death.
Besides omega-3 fatty acids that prevents erratic heart rhythms and regulate plaque formation in blood vessels, the amino acid arginine in walnuts improves the elasticity of blood vessels. Overweight people can help protect themselves from heart disease and diabetes by adding walnuts to their diet. A group of at-risk adults who were put on a walnut-enriched diet saw improved endothelial function, which impacts inflammation and controls blood pressure, according to study out of Yale University. Due to the strength of evidence supporting cardiovascular health, the Food and Drug Administration (FDA) approved a qualified health claim for walnuts in March 2004.
Numerous substances in walnuts, such as gamma tocopherol, polyphenols, and phytosterols, may offer protection against cancer development. In a study, reported in “Nutrition and Cancer“, studied whether consumption of walnuts could affect growth of human breast cancer tumors (MDA-MB 231) implanted into mice. After 35 days, the breast cancer tumors of the walnut fed mice were significantly less. Recent research from the School of Medicine at The University of Texas Health Science Center San Antonio demonstrates that eating a modest amount of walnuts can protect against prostate cancer. Scientists at the UT Health Science Center injected immune-deficient mice with human prostate cancer cells. Three of 16 mice eating the walnut-enriched diet developed prostate tumors, compared with 14 of 32 mice on the non-walnut control diet.”We found the results to be stunning because there were so few tumors in animals consuming the walnuts and these tumors grew much more slowly than in the other animals,” disclosed study senior author Russel Reiter.
Since there’s a high concentration of omega-3 fatty acids in walnuts, they’re important for brain health. Insufficient omega 3 intake has been associated to depression and decline in cognitive function. A study done at “Purdue University” demonstrated that children with a lower concentration of omega-3 fatty acids have a higher risk of hyperactivity, learning disorders, and behavioral problems. Although research has not found a way to ward off dementia cognitive decline may be preventable. Consuming specific foods, being physically active, and engaging in social activities may help maintain and increase cognitive health. Beyond protecting against age-associated problems, a British Journal of Nutrition animal study found that walnuts may improve working memory, problem-solving and motor function. The combination of antioxidants and alpha linolenic acid in walnuts may provide antiamyloidogenic, anti-inflammatory and antioxidative effects, thereby protecting brain cells. An in vitro study using walnut extract found that it counteracted oxidative stress and cell death caused by amyloid beta-protein, a major component of amyloid deposits and senile plaques in the brains of people with Alzheimer’s disease.
A Yale study reported in “Diabetes Care” finds walnuts improve blood flow in adults with type 2 diabetes. Endothelial function significantly improved after consumption of the walnut-enriched diet compared to the diet without walnuts. The scientists concluded that a walnut-enriched diet may improve endothelium-dependent vasodilatation in patients with type 2 diabetes, thus reducing overall cardiac risk. New research reported online by the “Journal of Nutrition”, found an inverse correlation between walnut consumption and risk of type 2 diabetes in two large prospective cohorts of US women: the Nurses’ Health Study (NHS) and NHS II. Scientists followed approximately 138,000 women over a 10-year period and found that those who ate two or more 1-oz servings of walnuts per week were 24% less likely to develop diabetes compared with those who ate fewer or no walnuts.
Walnuts have been associated to a positive effect on sperm development. Eating around two handfuls of walnuts a day ameliorates sperm health in young men, a study in the journal “Biology of Reproduction” suggests. In this study, 117 healthy men aged 21 to 35 were randomized either to continue eating their usual diet or adding 2.6 ounces of walnuts to their usual diet. Sperm shape, movement and vitality improved in men who added walnuts to their diet over twelve weeks. The control group experienced no changes.