Fresh concerns over safety of herbal preparations
They are much sought after for their health benefits. They have become common medicines in many Nigerian homes. But recent research has raised concerns that indiscriminate use of packaged herbal bitters may have a toxic effect on the spleen, pancreas and heart. CHUKWUMA MUANYA reports.
PLANT extracts, now popularised as 'herbal medicines', have been shown to prevent, treat, manage and cure several diseases from cough to cancer.
This proven efficacy has resulted in great patronage for any product that comes with the name 'herbal'. Most companies are capitalising on this window to rip in more profits. From toothpaste to creams, health drinks to breads, the story is same.
The latest craze is herbal bitters. The manufacturers in an aggressive marketing drive claim they are recipes for indigestion, weight loss, youthfulness, strength among others.
Medicinal, herbal bitters contain blended ingredients in a water or alcohol (tincture) base. Originally sold as a digestive aids because of their ability to increase the production of saliva and digestive juices, bitters became popular in Europe in the 1600s. This was due in part to the opening of trade routes with China, where the origin of bitters can be traced back more than 5,000 years.
Today, herbal bitters are used primarily as digestive stimulants, detoxifiers and antibacterial agents and can be taken either internally or externally, depending on the manufacturer and treatment.
Phytochemical analysis shows that bitters contain complex carbohydrates, alkaloids, vitamins and minerals that have antioxidant, antiviral and antispasmodic properties. It has been shown that these ingredients work together to reduce inflammation, control pain, relax muscles and improve digestion and elimination. Bitters can also be effective as appetite stimulants in some people.
According to a Professor of Phytomedicine at the University of Benin, Edo State, MacDonald Idu, "If you are suffering wound infections and rashes, foods containing bitter principles are the best antidotes, while bitters are also indicated for treating skin disorders, fever, jaundice and loss of appetite."
Idu said that several bitter components were bactericidal, germicidal and anti viral in their nature, as well anti inflammatory in effect. "Bitter foods are known to elevate the air mass element in your body and reduce the excess amount of ills in other elements. Oriental herbal texts indicate that herbal bitters are very light and cold in their nature and the typical taste is due to the presence of various components like caffeine, alkaloids and a bitter principle called berberine. The extreme dryness of bitters assists your body to get rid of excessive mucus, watery storage particles and help remove pus from the wounds," he said.
According to Oriental medicine, herbal bitters are beneficial as a slimming agent and this unique action helps people reduce their weight and increase bone weight.
"Bitter foods are also expectorants in removing mucus from your air passage, as well as improve circulation," Idu added.
Indeed, fresh herbal bitters from plants like Vernonia amygdalina (Bitter leaf), Ocimum gratissimum (scent leaf), Telfairia occidentalis (ugu), Citrus medica (lemon), Citrus aurantium (lime), Gongronema latifolium (utazi in Ibo, arokeke in Yoruba), among others have been shown to be effective and safe in relieving disease conditions. But fresh concerns have been raised over the safety of packaged ones.
Until now, most Nigerians believe that herbal medicines are natural and that medications of natural origin are not toxic or dangerous. There have been reports of acute and chronic intoxication resulting from the use of herbal remedies. Several researchers also reported that most herbal remedies exhibit organ specific toxicity, hence the delay in manifestation of toxic effects.
Lack of standardisation is a major concern regarding use of medicinal herbal medicines. Herbal medicines are complex mixtures in which the active ingredient may not be known or may be only a small per cent of the total product. Some are believed to achieve their beneficial effects through the combined actions of several ingredients.
However, little is known about chronic toxicities that might be associated with their prolonged use. There has been minimal research to assess possible systemic toxicity that might be associated with high doses or due to chronic administration of products.
Most herbal medicines are not registered with the National Agency for Food and Drug Administration and Control (NAFDAC). What NAFDAC does is to list the products after doing only toxicity tests.
So far, efforts made by regulatory authorities in ensuring safety of registered pharmaceutical products in Nigeria seem to concentrate on effects of these pharmaceuticals on renal and liver function test.
Researchers at the Toxicology Unit, Department of Pharmacology, College of Health Sciences, Nnamdi Azikiwe University, Nnewi, National Agency of Food and Drug Administration and Control (NAFDAC), Lagos Laboratory and Department of Biochemistry, College of Medical Sciences, Abia State University, Uturu, have alerted on the possibility of heavy metal toxicity from herbal products in Nigeria.
The researchers in a study titled "Heavy metal hazards of Nigerian herbal remedies" published in the Nigerian Journal of Pharmacology said that the result showed that 100 per cent of the samples tested contained elevated amounts of heavy metals. They added that the public health hazards from ingestion of herbal medicines should be identified and disclosed by in-depth risk assessment studies.
The study characterised the content of cadmium, copper, iron, nickel, selenium, zinc, lead and mercury in a random sample of Nigerian traditional products.
Ready-to-use herbal products were purchased from the open market and digested. The heavy metal content of the digested filtrate was determined.
Researchers have also demonstrated multiple organ toxicity of a Nigerian herbal supplement, U & D Sweet Bitter, in male albino rats. The study published in Pakistan Journal of Pharmaceutical Science suggests U & D Sweet Bitter may have toxic effect on the spleen, pancreas, and heart of male albino rat.
U & D Sweet Bitter is a registered herbal supplement prepared from roots, leaves, flowers and fruits of different herbs. It is very widely used and can be available in Eastern Nigeria. The marketing label acclaimed therapeutic indications in typhoid, malaria, and stomachache.
The researchers from Abia State University, College of Health Sciences, Uturu, Abia State, Toxicology Unit, Department of Pharmacology, College of Health Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State and Department of Biochemistry, Federal University of Technology, Minna, Niger State, wrote: "In the three month study, three groups of albino rats (150-200g), 539, 1077 and 1616mg/kg aqueous extract of U & Dee Sweet Bitter, were administered orally while deionized water was given to the control group. Animals had access to deionized water and were fed ad libitum with rat chow for 90 days.
"The feed and fluid consumption of the animals were measured on daily basis while the body weight was measured weekly. Animals were anaesthetised with ether after 90 days, bled sacrificed, heart, spleen and pancreas were excised and weighed. The following parameters were measured namely food and fluid intake, body weight, absolute and relative weights of the, spleen, pancreas, heart. Serum glucose, low density lipoprotein LDL (bad cholesterol), high density lipoprotein HDL (good cholesterol) were also determined.
"Food and fluid consumption were not significantly affected. A significant increase in absolute and relative weights was observed while the weekly body weight did not show any significant difference between the control and U & Dee Sweet Bitter treated groups. A significant decrease in total serum cholesterol, low -density lipoprotein (LDL), and high-density lipoprotein (HDL) were seen in U & Dee Sweet Bitter treated groups. This study suggests that U & Dee Sweet Bitter may have toxic effect on the spleen, pancreas, and heart of male albino rat."
Researchers have also questioned the safety of bitter orange (lime) herbal weight loss product. The Australian Therapeutic Goods Administration (TGA) is reportedly examining whether there are any risks associated with an over-the-counter (OTC) herbal weight loss programme sold in Australia.
The product called 'Mega Slim' was linked to serious health risks and this is not the first time its safety has been questioned. This is a concern because the average consumer believes products sold OTC, particularly by a pharmacist, must be safe.
Mega Slim contains a compound called Citrus aurantium or bitter orange (lime), which is a flowering evergreen tree or plant, native to tropical Asia. The dried outer peel of the fruit, without the white pulp layer, is used medicinally and the unripened fruit are a traditional flavouring in the liquor Curacao, the oil extracted from the peel of the fruit is used for a variety of ailments, mainly digestive.
However, phytochemical analysis shows that bitter orange has a complex chemical makeup - the peel contains flavones, the alkaloids synephrine, octopamine, and N-methyltyramine and carotenoids.
It has been shown that weight loss remedies contain between 100 - 200 mg of bitter orange extract in combination with other herbs-bitter orange extract commonly contains from 1.5 to six per cent synephrine and while it is considered safe in the small amounts found in foods, bitter orange is not safe when used in high doses.
Earlier studies suggest that Synephrine and N-methyltyramine, can cause hypertension and cardiovascular toxicity and frequent contact with bitter orange peel or oil can also cause adverse skin reactions; large amounts of bitter orange peel ingested by children can cause intestinal colic, convulsions, and even death.
It has been shown that bitter orange may also interact with medicines such as ulcer, anti-anxiety medication, blood pressure medications, cholesterol medications, allergy medication, fungal medications, Human Immuno-deficiency Virus (HIV)/Acquired Immune Deficiency Syndrome (AIDS) medications, sedation medication and anti-nausea medication and cause serious adverse effects.
Children and pregnant or breastfeeding women are advised not to use the herb as are people suffering from hypertension, tachyarrhythmia (any disturbance of the heart rhythm in which the heart rate is abnormally increased), or narrow-angle glaucoma.
As far back as 2002 scientists were issuing warnings regarding the use of bitter orange. Scientists at Georgetown University Medical Centre in the United States said at the time in a review published in the September issue of Experimental Biology and Medicine, that people taking weight loss products that contain the herb Citrus aurantium might be doing more harm to their body than good.
According to the researchers there was no reliable scientific evidence to support the use of Citrus aurantium for losing weight and more importantly, high doses of the herb, which contains synephrine, may not be safe as it could cause hypertension and also adversely interact with other drugs.
A complaint reportedly sent to the TGA has said that Mega Slim contains large amounts of bitter orange, which was linked to heart problems in a number of cases in Canada - two of which were fatal.
Mega Slim is distributed by the Victorian company Next Generation Supplements, which reportedly denies that there is any evidence to suggest it is dangerous to the health.
The TGA apparently warned the company in 2005 that it was breaking the law by making health claims for Mega Slim without having listed the product on the Australian Register of Therapeutic Goods, and told the company to cease making and supplying the product until a listing had been made but this happened again in 2005.
Experts say that unless advised by a doctor for a serious medical reason, fast weight loss can be harmful and programmes that promise quick weight loss should be viewed with caution. They say diet products and programmes which promise quick weight loss without effort, are suspect and to achieve long-term or permanent weight loss a person must change how they eat and exercise and there are no miracle weight-loss products or plans - to lose weight, you have to reduce your intake of calories and increase your physical activity and be skeptical about exaggerated claims.
Experts insist weight-loss programmes should encourage healthy behaviours which help people lose weight and which they can stick with every day and safe and effective weight-loss programmes should include healthy eating plans that reduce calories but do not forbid specific foods or food groups.
Weight loss experts recommend that depending on a person's starting weight, losing weight at a rate of half to at the most two kilos per week.
Scientists say the use of Citrus aurantium and other herbal weight loss products should not be considered safe simply because they are available OTC.
Idu urged for caution on the use of packaged herbal bitters. He recommended home-made bitters, a combination of scent leaf, bitter leaf, Telfairia occidentalis leaf (ugu), Gongronema latifolium leaf (utazi in Igbo)) and lime peels blended into a juice and taken first thing in the morning and last thing at night.
"Avoid herbal bitters if you are pregnant or nursing and do not treat children with bitters. You should also avoid or stop taking bitters if you have been diagnosed with the following conditions: Kidney disease, Irritable Bowel Syndrome (IBS), Crohn's disease and Chronic gall bladder issues," Idu said.
He said that bitters could also cause adverse reactions if taken in combination with other drugs like sedatives, antidepressants and tetracycline antibiotics.
"Read the instructions and recommendations on the bottle carefully before you begin treatment and do not exceed the recommended dosage for bitters or any other herbal medication. You should always consult a physician before beginning treatment," he said.
