The United States authorities declare tree nuts to be a food offering protection against cardiovascular illness
The FDA (Food and Drug Administration), the American body which regulates and monitors hygiene and health aspects of pharmaceuticals and foods, has issued an official statement concerning the beneficial effect of tree nuts on cardiovascular health. The statement explains that scientific evidence suggests, but does not prove, that consuming 45g of tree nuts as part of a diet low in saturated fats can reduce the risk of coronary illness. Since 1993 the FDA has been monitoring and approving any inclusion on food packaging or containers of phrases or slogans linking the foods to health. Thus, the FDA approved and declared the following links existing between foods rich in calcium and the prevention of osteoporosis, foods low in saturated fat and cholesterol and the prevention of cardiovascular illness, and antioxidant vitamins and cancer, among others. This latest statement about tree nuts is one of only six statements approved by the FDA in relation to cardiovascular health, and is the first of them to refer to a natural food. The FDA approved the statement after appraising the abundant scientific evidence corroborating the beneficial effect of tree nuts on the human body; numerous research studies exist which prove the effects for health. The first studies conducted on large population groups showed that individuals who regularly consumed tree nuts displayed a lower risk of cardiovascular illness. The data gathered showed reductions of around 50% in the risk of suffering a heart attack in consumers of more than five portions of tree nuts a week. Subsequently, dietary intervention studies were conducted in which falls in LDL cholesterol (bad cholesterol) levels of the order of 9-20% were observed in volunteers after consuming tree nuts, and of 4-16% of total cholesterol. This reduction was suggested to be the main cause of the reduced risk of heart attack and coronary illness observed in tree nut-consuming groups. Subsequent studies also showed that tree nuts' antioxidant effect may help to avoid oxidation in our bodies, avoiding the formation of thrombi or clots which might lead to some kind of vascular incident. Recent research assessed the effect of these foodstuffs on other pathologies such as cancer or diabetes, and tree nut consumption was linked to a reduced risk of some types of cancer, including prostate cancer, though this link remains to be confirmed. As regards diabetes, some studies indicate that individuals who regularly consume tree nuts have a lower probability of suffering from diabetes; moreover, a recent study conducted with diabetics also showed that regular consumption of tree nuts does not affect glucose levels in the blood and that in fact it has positive effects on the lipid profile of diabetes sufferers. The nutritional profile of tree nuts is largely responsible for their effects on the human body. Tree nuts have particularly low levels of saturated fats (only between 5 and 12% of their weight is saturated fat); while between 45 and 63% of their weight consists of mono and polyunsaturated fats (omega 3 type in the case of walnuts) like those contained in olive oil and similar to those in bluefish, with beneficial effects in terms of preventing cardiovascular problems. They also contain other components to protect the heart such as vitamin E, selenium, magnesium and several phytochemical components with hypocholesterolemic effects (i.e. causing a reduction in cholesterol levels in the blood) or providing cardiovascular protection. The antioxidant capacity of tree nuts is another of their main features; recently Halvorsen and her colleagues published a study in which the antioxidant qualities of various foodstuffs of vegetable origin were analysed: walnuts proved to be the foodstuff with the second-highest antioxidant content. To complete their excellent health cocktail, tree nuts are rich in fibre, a component which contributes to lowering absorption of cholesterol, to reducing synthesis of bodily cholesterol and to better intestinal transit. For all these reasons nutrition experts agree on the importance of tree nuts, recognising their beneficial effects and advising the general public to consume them regularly. Spanish nutrition societies currently recommend an intake of one to five portions a week of tree nuts, where one ration is roughly a handful.
Keywords
Nutrition & Health