A lot of people avoid taking bitter leaf juice or even using it to prepare meals because every part of the leaf is bitter. It might be unpleasant but its daily intake of Nigeria’s indigenous staples or as a spice in food may help lower blood pressure.
In a new study, researchers who systematically assessed studies on the benefits of bitter leaf suggested that hypertensive patients should take more bitter leaf soup or juice to reduce their blood pressure.
They concluded that bitter leaf can lower blood pressure because it contains chemical constituents like flavonoids which can increase the availability of nitric oxide (NO) in the body and potassium which can cause relaxation of the blood vessels, thereby lowering blood pressure.
For the systematic review, the researchers looked at research studies by experts from 2011 to 2021. The results of the six selected articles indicate that bitter leaf is able to lower blood pressure. This is proved in the blood pressure lowering experiments of cats, suggesting that bitter leaf can affect a significant drop in blood pressure in cats with normal blood pressure levels.
The 2022 study was in the International Journal of Biomedical-Nursing Review.
Hypertension is a non-communicable disease caused by genetics, stress, and lack of physical activity. It is included in the silent disease. This is because the patient will only know that he has hypertension after checking his blood pressure and because this disease does not have distinctive symptoms. So far, no effective drugs have been found to cure high blood pressure.
Bitter leaf has high iron content. Iron is the main component of haemoglobin carrying oxygen from red blood cells. Also present in it is Vitamin C and high amounts of minerals like potassium. As such, it has many benefits for treating various diseases, including diabetes, colorectal cancer, stomach aches, skin blemishes, typhoid fever, malaria fever and constipation.
Previously, researchers said that adding bitter leaf to the diet had a lowering effect on bad and total cholesterol concentration at both 5% and 10% dietary incorporation levels under laboratory conditions in animals.
The study assessed the effect of feeding both a high-fat diet (HFD) and methanol extracts of Vernonia colorata (MEVC) on lipid profile (amount of cholesterol and fat in the blood) and body weight changes in 30 Wistar albino male rats aged between 10 and 12 weeks.
It was in the 2021 edition of the journal, Biokemistri. It involved Ijeoma Nina Eke-Ogaranya and Anthony Chibuzor Nnamudi at the PAMO University of Medical Sciences, Port Harcourt, Rivers State, in collaboration with Ifeoma Irene Ijeh at the Michael Okpara University of Agriculture, Umudike, Abia.
Different amounts of the extract of Vernonia colorata were administered orally on a daily basis. Body weight was measured weekly while the amount of cholesterol and fat in the blood was measured at the end of the study which lasted for 10 weeks.
The study found that the bad cholesterol and fat-lowering effects of extracts of Vernonia colorata were similar to Orlistat, the drug designed to treat obesity. It also resulted in a dose-dependent decrease of 22.2% and 15.8% in the body weight of animals that were administered 1000mg/kg and 200mg/kg of methanol extract relative to a 12.5% decrease in the Orlistat group.
There was a significant decrease in LDL cholesterol concentration upon concomitant feeding of a high-fat diet and administration of methanol extract of Vernonia colorata relative to the high-fat diet control group.
Vernonia colorata is suggested to stimulate cholesterol-lowering activity, thereby ensuring the conversion of more cholesterol into bile acids, thus resulting in the reduction of total blood cholesterol level due to increased excretion.
According to the study, “The dose-dependent steady loss in weight could have been as a result of the presence of anti-nutritional factors such as saponins in Vernonia colorata which may reduce lipid distribution and nutrient availability by delaying the absorption of fats in the intestines.”
Previous reports state that regular intake of the bitter leaf also protects the vital organs from damage due to toxicity from poisonous substances. A study published in the Journal of Food and Nutrition Sciences demonstrated how bitter leaf could be used to prevent kidney, liver and heart damage.
According to the study, the ethanol leaf extract of Vernonia amygdalina ameliorates and protects the liver, kidney and heart of male albino Wistar rats against theobromine-induced toxicity and modulates the adverse effects on lipid profile.