African walnut, beetroot protect against salt-induced hypertension —Scientists
High blood pressure is a symptomless “silent killer” that quietly damages blood vessels and leads to serious health problems. While there is no cure, making small changes like daily intake of African walnuts can make a difference in lowering blood pressure.
In a study, experts found that African walnuts possess a blood pressure-lowering effect in hypertensive rats. It caused a significant reduction in the systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial blood pressure (MAP) and heart rate and blood cholesterol levels.
There was no significant difference in SBP, DBP, MAP, heart rate and body weights of experimental animals with salt-induced high blood pressure that was treated with water extract of African walnut and those treated with lisinopril, a conventional hypertensive medication.
This 2018 study, designed to investigate the potential of Africa walnuts as an antihypertensive agent on blood pressure, heart rate, lipid profile, and body weight was published in the American Journal of Hypertension Research.
A total of 30 male Wistar rats were used for this study. The rats were randomly divided into six groups of five rats each. Hypertension was induced in the rats except for the group one which served as the normotensive control group.
The rats induced with hypertension were treated with 70 mg/kg, 140 mg/kg, 210 mg/kg body weight of water extract of African walnut and lisinopril 5 mg/kg respectively for additional 21 days. Measurement of blood pressure and body weights were taken weekly during treatment while lipid profile was analyzed at the end of treatment.
To prepare the extract, the researchers boil the nuts for two hours and allowed to cool. The shells were removed and the white coloured nuts washed thoroughly. The nuts were grounded with an electric blender, macerated with water and filtered.
The researchers suggested that the significant decrease in blood pressure may be due to the action of flavonoids and saponins contained in the water extract of African walnut.
According to them, African walnuts have been proven effective for keeping the blood vessels that supply the heart flexible and reducing the damage caused by fatty food due to its high content of Omega-3 fatty acids, phytosterols and antioxidants.
The researchers, who said that the consumption of African walnuts should be encouraged, declared that there was the need to research on its possible preservation as the plant is seasonal.
Further studies, they said are required to ascertain the mechanism of action through which it also reduces blood pressure.
African walnut is known as Ukpa by Igbos, Awusa by Yoruba, and Gawudi bairi by Hausas. The plants is cultivated principally for the nuts, which are cooked and consumed as snacks. It has been proven to have nutritive, medicinal, agricultural and industrial values over the years.
In traditional Chinese medicine, African walnuts are said to tone kidneys, strengthen the back and knees, moisten the intestines and move stool.
African walnut is known to be rich in protein, fat, carbohydrate but low in fibre and ash content. The nut has also been found to be very good source of Vitamin A, B1, B2, B6, E, folate, potassium, sodium, manganese, copper, chloride, iron and ascorbic acid.
It also contains plant-based polyunsaturated fatty acids such as alpha-linolenic acid. Furthermore, these nuts contain Omega-3 essential fatty acids and since it cannot be manufactured within our bodies and must, therefore, be ingested.
Previously, researchers have revealed African walnut to be useful in ulcer treatment as well as in tackling male fertility by boosting sperm productions in testicles.
Chronic salt – loading has been reported to increase blood pressure in rats. But incorporating flavourful herbs and spices into a daily diet can also help to cut back on salt intake. Examples of herbs and spices to take include basil, cinnamon, ginger, thyme and garlic.
Garlic can help reduce hypertension by increasing the amount of nitric oxide in the body. Nitric oxide helps promote vasodilation, or the widening of arteries, to reduce blood pressure.
Eating fresh fruits and vegetables, which are rich in potassium, can help lower blood pressure. Such fruits and vegetables include leafy greens, tomatoes, potatoes and sweet potatoes, bananas, avocados and oranges.
Small amounts of beetroot or dietary nitrates added to salty foods may help to also protect against increases in blood pressure. Researchers in a study reported that beetroot juice and nitrate supplements were more than 100 times more potent than potassium in protecting salt-sensitive rats against blood pressure rises.
Writing in the journal Hypertension, scientists found that fortifying salty foods with “surprisingly small amounts” of nitrate-rich vegetable products prevented increases in blood pressure in male Dahl salt-sensitive rats.
They declared: “given that leafy green and root vegetables contain large amounts of inorganic nitrate, these findings raise the possibility that fortification of salty food products with small amounts of a nitrate-rich vegetable concentrate may provide a simple method for reducing the risk for salt-induced hypertension.”