Three traditional vegetables show strong action against obesity

By Gatonye Gathura

Cowpea, amaranth and pumpkin leaves have helped experimental obese animals at Kenyatta University, quickly shed off excess weight.

“We have confirmed scientifically that these vegetables contain chemicals that fight obesity,” says lead investigator, Kathryn Wanjiku Nderitu.

Shedding that extra fat, Nderitu, told the Standard on Wednesday, can keep away heart diseases, sleep problems, diabetes and early death.

“Our study has conclusively demonstrated that leafy extracts from amaranth (pigweed), cowpea and pumpkin have vital chemicals important in managing obesity.”

The traditional vegetables, which are on a comeback among most urban families, the study shows fights obesity and overweight through three mechanisms. “Extracts from the vegetables decrease body mass, lowers food intake, and burns fats in blood,” says the recent study.

The researchers from Kenyatta and Eldoret universities had fed extracts from the vegetables to fattened mice and now report dramatic results.

The experiments, carried out at Kenyatta University in Nairobi involved 45 female mice, some fattened with the drug Depo Provera, which is used as an injectable birth control by women.

When the fattened mice were treated with extracts from the leaves of pumpkin (Cucubita pepo) pigweed (Amaranthus dubius) and cowpea (Vigna unguiculata) they were confirmed to shed weight.

The study published last week (30th August) in the journal of Evidence-Based Complementary and Alternative Medicine, further investigated the specific compounds in the vegetables responsible for the antiobesity action.

Consequently, Wanjiku said the leaves obtained from Marula village, Eldoret Sub County, Uasin Gishu County, were tested for probable chemical compounds.

The extracts were found to contain alkaloids, terpenoids, diterpenes, flavonoids, phenolics, saponins, anthraquinones, steroids, and tannins, many found to have antiobesity actions.

“We were seeking out scientific evidence to validate or otherwise the traditional medicinal use of these vegetables. It seems they have been vindicated,” says Wanjiku.

The chemicals reduce obesity by either burning excess fat in the blood serum, reducing appetite for food and decreasing body mass.  “The study, therefore, confirmed the important role in the use of African leafy vegetables in prevention and management of obesity.”

Obesity the study overseen by Mathew Piero Ngugi of Kenyatta University says obesity can lead to other disease such as diabetes, heart problems, sleep complications and early death.

“We tell our patients to eat lots of traditional vegetables especially to prevent the development of lifestyle diseases,” says Shadrack Moimett of Koibatek Herbal Clinic.

Their advice, he says is based on inherited traditional knowledge over the years and now welcomes the new confirmatory evidence generated through modern science.

“We have always known these vegetables cleanse the body systems in what modern science call detoxification keeping some heart problems, cancers, bad fats and diabetes away,” says Moimett.

It took 28 days to carry out the scientific study; Wanjku says their primary objective was to confirm that the vegetables actually work against obesity and identify individual compounds responsible for this.

However, she said they did not go into how much a human need to eat and for how long to reduce obesity or be protected against the various lifestyle diseases.

“We advise out patients to at least eat vegetables as often as daily,” says Moimett.

The World Health Organization (WHO) recommends at least 5 servings of fruits and vegetables a day.

To improve overall health and reduce the risk of certain non-communicable illnesses like heart diseases, some type of cancer, diabetes and obesity, WHO recommends consumption of at least 400grams or five servings of fruits and vegetables per day.

A serving of vegetable is equivalent to two  cups (of 250ml) of uncooked, or 1 cup cooked green leafy vegetables while a serving of fruits is equivalent to one medium whole fruit of half a cup of chopped fruits.

However the only national survey of non-communicable diseases carried out by the Ministry of Health and WHO in 2015 showed only six per cent of Kenyans consume the recommended amounts of vegetables and fruits per day.

Also only one in five Kenyans have ever been advised to eat at least five servings of fruit and or vegetables by a health worker.

But there is still a third, important food ingredient to keep you away from an early grave according to the world’s most diverse and largest study published on Thursday in The Lancet.

Legumes such as beans, black beans, lentils, peas, chickpeas, and black-eyed peas the study says are the third magic food component against heart and other lifestyle diseases.

“We now have proven that people who eat more vegetables, fruits and legumes live longer and  have fewer health related problems,” say Victoria Miller, of McMaster University, Canada and lead author of the new study.

In an email to this author last week Miller said they had studied 135,335 people from all continents of the world for 10 years.

An interesting finding from this study and important for the poor Kenyan was that while the WHO recommends 400grams of fruits and vegetables or five servings per day, a little less may also be good enough.

“Our findings suggest that even three servings per day (375 g/day) also has sufficient health benefits against most lifestyle disease  and should be encouraged,” said Miller.

Miller says while both raw and cooked vegetables confer health benefits, uncooked helpings have more advantages.

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