Walnuts belong to the tree nut family, along with Brazil nuts, cashews, hazelnuts, macadamia nuts, pecans, pine nuts, and pistachios. They are three main varieties: English or Persian Walnut, Black walnuts and White walnut. All of them are grown the world over; black walnuts are more common in Nigeria. The biggest producers of walnuts worldwide are in descending order:- China, U.S.A., Iran, Turkey,
Walnut has a very thick shell on the outside, when cracked it reveals an off-white kernel with two unequal lobes covered by a thin transparent sheet. The lobes are edible.
Walnut is rich in Water (4 percent); Energy (654 Kcals per 100grams); Protein (15 percent), Fat (65 percent); Carbohydrates (13 percent; Fibre 6.7 percent, sugar 2 percent); Minerals (Magnesium, Phosphorus, Calcium, Potassium, Manganese and Zinc); Vitamins (B-Complex, and E) and Phytochemicals (Ellagic acid, Carotenoids and poly-phenolic compounds).
The bulk of fat is in the form of Omega -3 and Monounsaturated fatty acids such as Oleic Acid
The health benefits of Walnuts are due to these nutrients listed above.
Research shows that eating about seven walnuts may be all it takes to take advantage of their beneficial nutrient properties.
1. Help reduce risk of Cancer
Walnuts may help reduce not only the risk of prostate cancer and also breast cancer by virtue of what it contains:–phytochemicals. According to the United States Department of Agriculture, consumption of diet rich in phytochemicals can reduce the risk for heart disease and cancer.
Walnut is rich in Ellagic acid and carotenoids; human research shows that ellagic acid has both anti-cancer and anti-oxidant properties. It is said to reduce the risk of cancer of the breast and prostate among others but more studies need to be done.
2. Protect the Heart
Walnut is very rich in the mineral called Potassium which is known to help the heart and reduce blood pressure by relaxing the blood vessels.. Low potassium can cause Constipation, lack of appetite and poor working of the heart.
Walnuts also contain Omega -3, several monounsaturated fatty acids like Oleic acid and several polyunsaturated fatty acids like Alpha-linoleic Acid (ALA). All these reduce the blood level of bad cholesterol and increase the blood level of good cholesterol.
Walnut is very rich in Magnesium which helps with regulating heartbeat,
3. Decelerate Aging
Antioxidants are crucial to your health, as they are believed to help control how fast you age by combating free radicals, which are at the heart of age-related deterioration.
Walnuts contain several Phytochemicals:-Ellagic acid, Carotenoids and Poly-phenolic compounds; these are all Anti-oxidants.
4. Assist in Weight Control
Eating fibre – rich foods like walnut helps in weight control and therefore prevents obesity. Fibre-rich foods are bulky and fill the stomach easily and there is therefore the feeling of fullness and satisfaction.
A study conducted at the San Diego School of Medicine of the University of California, found that eating one and half handful of walnuts daily reduced weight after six months. About 245 overweight women were involved in the study.
5. Improve Male fertility
Walnut contains a lot of zinc which is a co-enzyme of substances necessary for the formation of sperm. Walnut therefore improves male fertility. According to some studies, adding 75 grams (a bit over one-half cup) of walnuts daily significantly improved sperm quality, including vitality, motility, and morphology.
6. Help in management of type 2 Diabetes
Walnut is rich in carbohydrates, about 13 percent; but about half of this is fibre, walnut is 6.7 percent fibre. Consequently, one gets full easily, besides walnut is only 2 percent sugar.
Overweight adults with type 2 diabetes who ate a handful of walnuts daily had significant reductions in fasting glucose levels compared to those who did not.
7. Help prevent constipation
Walnut contains fibre (about 6.7 percent) which is known to ease constipation and also reduce the risk of colon cancer. Fibre makes the stool bulky and so eases bowel movement.
8. Reduce Risk of Heart Disease/Stroke
Walnut contains fibre, mostly soluble fibre; the latter reduces absorption of cholesterol and bile acid (which are also rich in cholesterol) from the small intestines, thereby reducing blood cholesterol level. When soluble fibres are broken down by bacteria in the intestines, some fatty acids released are said to reduce the production of cholesterol by the liver. By lowering blood cholesterol, fibres help to reduce the risk of heart disease and stroke; both are associated with high blood cholesterol Level. Stroke results from narrowing/blockage or rupture of blood vessels supplying blood to the brain.