Walnut or Juglans regia is an edible nut from the botanical family Juglandaceae. As a nutrient-dense nut, it offers a lot of health benefits to the human body. These benefits include lowering blood cholesterol, managing diabetes, preventing cancer, strengthening the bones, and reducing inflammation.
Botanical name: Juglans regia
Botanical family: Juglandaceae
The walnut is the seed of the fruit of the walnut tree, Juglans regia. The walnut is not the fruit of the walnut tree, but a seed within the fruit. So, it is botanically not a true nut, but seed of a drupe. The fruit is just a normal drupe with a fleshy pericarp and mesocarp, and a woody endocarp (the seed) which is known as the walnut.
All walnuts can be eaten directly, in either raw, toasted, or pickled forms. They are used as ingredients in other foodstuffs. Walnuts soups, pie, coffee, and cake are various food preparations that walnuts are used as main ingredients. They can be processed to make several products such as walnut butter. Walnut can also be pressed to extract walnut oil, which is mainly used in salad dressings. These nuts are also used in ice cream toppings, or as garnishes on some foods.
However, most of the above uses have few scientific evidences to back them up. That’s why they are labelled folk healing.
Walnut, believed to have originated from central Asia, is one of the most concentrated food sources of nutrients. It is among the nuts with the highest caloric content, about 654 kcal per 100 g.
- Fat – Walnuts are very rich in fats. It makes up about 65% of its weight, even greater than that in almonds and peanut. These fats are formed mainly of unsaturated fatty acids, with more of polyunsaturated acids. Among these two fatty acids, the following stands out:
- Linolenic acid – This helps reduce cholesterol and triglycerides level in the blood. It also helps stop inflammatory actions and prevents the formation of blood clots in the vessels.
- Linoleic acid – This is an essential fatty acid the body cannot do without. It helps lowers cholesterol level. It is also involved in the production of antibodies (substances in the blood that fights diseases), and in the formation of nerve tissue.
These two acids, linoleic and linolenic, are very important to the body, and walnuts are one of their best food sources.
- Proteins – Walnuts contain proteins in about 15% of their total content, but these proteins are deficient in an essential amino acid called methionine. In order to complete the proteins, walnuts are combined with whole grains like rice or wheat, which are rich in methionine. Another advantage of mixing nuts and grains, is the ability of the nuts to complete two important essential amino acids that are deficient in whole grains this time around.
- Carbohydrates – Walnut is among the lowest oil-bearing nut in carbohydrates, only at about 13.5% of its total content. This is one of the reasons why walnuts are tolerated by the diabetics.
- Vitamins – Walnuts are rich in B group vitamins, mainly vitamin B1, which is important for the functioning of the heart, and vitamin B6, which is involved in red blood cell production. However, they are poor in vitamin C and vitamin A.
- Minerals – Walnuts are rich in phosphorus, potassium, and trace elements like zinc, copper, and manganese. They also contain a significant amount of calcium, iron, and magnesium, but are very poor in sodium.
7 Benefits and medicinal uses of walnut
- Lowers blood cholesterol level
- Prevents coronary heart disease
- Manages diabetes
- Fights nervous system disorders
- Improves sexual performance
- Prevents cancer
- Fights inflammation
We have seen that the two fatty acids, linolenic and linoleic, present in walnuts help lower cholesterol level. A research published in the American Journal of Clinical Nutrition, found the consumption of walnut to significantly decrease total cholesterol and LDL or bad cholesterol levels in the body (1). This beneficial action translates to a better heart health and improved blood circulation.
Excess cholesterol in the body is very dangerous to the cardiovascular health, as it can buildup in our arteries and block blood flow to vital organs such as the heart and the brain. And such cases can lead to deadly conditions like heart attack and stroke. By adding just a few pieces of walnut to your diet, you are actually taking beneficial steps in protecting your overall cardiovascular health.
Coronary heart disease
Walnut is very friendly to the heart. Its consumption may be very beneficial in preventing coronary heart disease due to:
- Its cholesterol-reducing property which we have seen above.
- Its high B group vitamins content, which are necessary for the proper functioning of the heart.
- Its richness in fatty acids, as they make part of the energy source for the cells of the heart. Just as the body cells use glucose as a fuel, the heart cells use fatty acids as part of their fuel.
There are many published reports suggesting how walnuts can reduce the risk of developing type 2 diabetes. A research published in 2015 found walnut to improve diet quality, endothelial function, total and LDL cholesterol level, but had no effects on blood glucose level and pressure (2).
Nervous system disorders
Due to the richness of walnut in essential fatty acids, which are directly involved in metabolism of neurons, and other important substances, they may be found beneficial for those suffering from nervous system disorder like depression, stress, and irritability. They can also be useful to knowledge workers and even students, as they boosts brain functioning.
Walnuts are said to increase a man’s potency, and improve sexual performance in general. There are also many reports that have shown how eating a walnut-enriched diet may improve sperm movement and its quality by reducing lipid peroxidation.
Walnuts are a rich source of antioxidants such as polyphenols. These antioxidants present in walnuts can fight the activities of free radicals, whose interaction with body cells might lead to the growth of cancer. Not long ago, researchers have identified numerous compounds in walnuts to have cancer-prevention properties. Some of these compounds include fatty acids, tocopherols, β-sitosterol, and pedunculagin (3).
By adding just a few grams of walnuts to your diet, you can reduce your chances of developing any type of cancer.
A research conducted in 2008 found walnut to possess some anti-inflammatory properties (4). These properties were partly attributed to an acid present in walnut, known as ellagic acid. The research further suggested how its findings serve as a basis for the beneficial effect of walnut on cardioprotection and bone loss.