The Nutritional Importance of Groundnut to Human Health

By Ogunsola Samuel Sunday


Groundnut, botanically named as Arachis hypogeal, is considered a vital source of nutrients. It is rich in calories, and contains many nutrients and minerals, antioxidants and vitamins that are essential for optimal health. Studies have shown that groundnuts, together with its butter and oil, significantly reduce the risk of heart disease when consumed daily. Groundnuts have been recognized as a protein source, with researches showing that 100g of groundnut contains 23.68g protein.

Groundnut prevents diseases like pellagra and severe skin disorder by supplying enough tryptophan to the body. Groundnut has been referred to as a poor man’s protein as it is readily available at affordable price. According to the United States Department of Agriculture, Arachis hypogea contains 21.51g of carbohydrate per 100g. The major class of carbohydrate present in groundnut is starch which is a homopolysaccharide made up of alpha-D glucose residues joined together by glycosidic bonds. Groundnut supplies carbohydrates to the muscle which are utilized for doing work and they are stored in the liver as glycogen, released for use as and when necessary.

Fatty acids that are present in groundnut belong to the category of lipids. In addition to carbohydrates, they are also considered as energy producing biomolecules. In terms of fatty acids present, edible part of roasted groundnut have 6.893g saturated fatty acids, 24.64g monounsaturated fatty acids (oleic acid) and 15.69g polyunsaturated fatty acids. The presence of high mono and poly unsaturated fatty acids reduces the risk of coronary heart diseases.

Groundnuts are also vital sources of the water soluble vitamins for the body, along with vitamin E which is fat soluble. The vitamin E supplied by groundnuts is a dietary antioxidant that helps to protect cells from oxidative stress, a normal, yet damaging, physiological process. 100g of groundnut contains 0.44mg of thiamine which helps in preventing beriberi. It is also known that a deficiency of vitamin B2 leads to cheliosis (fissures of angles of the mouth), angular stomatitis (throat infection) and mouth ulcers. All these can be prevented by taking a diet rich in vitamin B2, and groundnuts are a potential source of vitamin containing 0.098mg of riboflavin.

Vitamin B5 is also found in good amounts in groundnuts. Chemically, vitamin B5 is a dipeptide consisting of pantothenic acid. Pantothenic acid in humans is needed for the formation of coenzyme A, a factor which is responsible for many vital reactions in the human body such as Krebs cycle, synthesis of cholesterol and synthesis of heme. Vitamin B9 (folate) has been found to be present in groundnut, leading to its ability to protect against cancers of the lung, colon and cervix. The vitamin B9 supplied by groundnut is also useful for human growth and helps in the mechanism of normal nerve and brain functioning.

Minerals such as magnesium, calcium, phosphorus, zinc, copper and selenium are abundantly present in groundnut. Therefore, regular addition of groundnut to normal daily diet can help in strengthening bones, teeth and gums, healing of wounds, prevention of stunted growth, diarrhoea, impotence and hair loss. It has anti-aging effects, while also preventing or delaying the onset of cancer.

Despite all these, there are risks to eating groundnuts. One of these is a significant risk in eating raw groundnuts when a carcinogenic substance called aflatoxin is present. This poison is produced by a fungus known as Aspergillus flavus. Also, though it may occur rarely, eating contaminated groundnuts can cause liver diseases, and a 1974 study suggested that consuming large amounts of groundnut oil can cause clogging (blocking) of the blood vessels, especially the arteries.

It has been discovered that in 0.4-0.6% persons, particularly in children, consumption of groundnuts in any form lead to allergic reactions called peanut allergies, some of which are very severe. These may develop during childhood or could be genetically due to a family history of peanut alergy. The symptoms associated with peanut allergy may range from oozing and skin rashes to swelling of face to shortness of breath or wheezing.