By Peter Samuel
Nzu, in the Igbo language, South East of Nigeria, is also known as Calabash chalk. It is a geophagic material consumed by many pregnant women and breastfeeding mothers as a remedy for morning sickness in most African countries.
Consuming nzu (calabash chalk) during pregnancy has formed a critical subject of discourse on my health and community-based platforms, as to whether it is good or bad for pregnant women and their unborn babies.
Meanwhile, some persons who spoke with HSA explained that the practice of consuming Nzu can have severe adverse health impacts on both the mother and the fetus, due to high levels of toxic substances like lead and arsenic, as well as harmful microorganisms in it.
Geophagia, the deliberate consumption or craving for eating earth, soil, chalk, or clay, is an ancient practice common to both animals and humans.
The practice is not limited to any geographic region or sex, but has become a common habit cutting across all social classes. It is highly prevalent in situations like poverty and famine to suppress appetite, and also in some psychiatric conditions like pica, compulsive indiscriminate eating of non-nutritive substances.
In most African countries, calabash chalk or calabash clay is among the most common forms of geophagia. Popularly called nzu in Nigeria, calabash chalk is known as La Craie or Argile in French, and Mabele in the Congo.
It is usually found in soil (mining pits) and occurs naturally as a light brown to almost white solid that is relatively soluble in water.
Calabash chalk is marketed in the raw form or processed by combining clay, sand, wood ash, or salt; packaged as powder, molded blocks, or pellets, and is readily available in open shops.
It is consumed by many because it is believed to have various ethnobotanical uses. It is used as an antacid, antidiarrheal, contraceptive, nutritional supplement, wound healing, and skin beautification agent.
It is also used for the treatment of skin diseases, fetal growth and well-being during pregnancy, and sociocultural activities. In general, pregnant women tend to consume more calabash chalk.
They use calabash chalk as a remedy for morning sickness and to satisfy their increased appetite and other peculiar desires. Being an earth material, calabash chalk is not unlikely to be contaminated with microorganisms or heavy metals, which may even increase during processing and/or storage.
Nzu can cause inflammation, edema, and hemorrhages in the stomach and esophagus. The chalk can contain harmful soilborne pathogens, such as bacteria, fungi, and parasites, which can cause foodborne illnesses.
Studies have shown that nzu can cause damage to the liver, spleen, and femur bones. Pregnant women with a suppressed immune system are particularly vulnerable to these risks.
Studies on the analysis of calabash chalk are currently very few, but the available data indicate that it contains heavy metals, with qualitative and quantitative compositions varying by geographical location.
However, it is believed that aluminum is a significant constituent, probably because kaolinite is present in most calabash clays. Others include lead, arsenic, and chromium.
This is important, especially as pregnancy is a delicate and vulnerable period, and is generally unsafe for many chemicals.
A medical doctor, certified food scientist, and Clinical Nutritionist, Prof. Henry C. Uro-chukwu, emphasized that nzu has no nutritional or medical value and can jeopardise the health of both mother and child.
“Nzu is called pics. It has no nutritional or medical value. Instead, it’s harmful because it depletes iron stores and therefore leads to anaemia in pregnancy, a situation that can jeopardize both the baby and the mother.
“For those who have already consumed it, it is best to improve intake of vegetables, fish, and legumes and avoid further intake.”
While traditionally used for perceived benefits like relieving nausea and providing minerals, eating nzu (calabash chalk) is associated with significant health risks due to potential contamination with toxic heavy metals like lead.
The potential for harm, including neurological damage, outweighs any supposed health benefits, and medical professionals strongly advise against its consumption.
It is sometimes consumed to provide minerals like calcium and iron. It is believed to help with diarrhea and other stomach issues by binding to toxins in the gastrointestinal tract. It can be eaten to suppress hunger.
The negative impact of consuming nzu apparently outweighs any supposed health benefits. Calabash chalk can be contaminated with toxic heavy metals like lead, arsenic, and chromium, which can cause poisoning, nerve damage, and developmental issues.
High levels of lead can lead to impaired cognitive function and other neurological problems. Instead of supplementing minerals, it can actually cause deficiencies. For instance, lead in the chalk can lead to low potassium and iron levels.
Exposure to heavy metals like lead is hazardous for the developing fetus and can lead to developmental harm. It can cause muscle weakness, low blood levels, and can be anxiogenic (anxiety-inducing).
In her reaction to the consumption of nzu, the Chief Nursing Officer, Government House Clinic, Abakaliki, Nurse Egwu Ogechi, emphasized that the consumption of the substance has the potential to harm unborn babies.
“Pregnant women are advised against taking white calabash because the edible clay contains lead, and consuming it can cause lead poisoning and harm to the unborn baby.
“It could also lead to various health issues, including health risks for the mother. It could lead to muscle weakness, nerve damage, an inflamed stomach, which could cause discomfort for the mother, poisoning, low blood levels, and constipation.
“White calabash, also known as nzu, can also cause health risks for the unborn baby, such as poisoning, impaired normal development, behavioural disorder, elaborated risk of school dropouts, and potential link to criminal behaviour and juvenile delinquency.
“Normally, pregnant women have Pica and crave for unusual things most times, but instead of craving for nzu, they should consider seeking medical attention for proper evaluation and guidance.”
She called on pregnant women to focus on taking a balanced diet rich in essential minerals and vitamins. This will help them to learn about safe and healthy practices during pregnancy.”
A pregnant woman, Mrs. Veritas Oge from Afikpo Local Government Area of Ebonyi State, said she will not take nzu for her pregnancy.
“No, I never did whenever I got pregnant. There is no particular reason for it. Some crave it. Maybe because they want to eat it, just like a normal person would crave a specific kind of food. There is no health benefit to consuming nzu.
“My advice is that women should stop consuming nzu whenever they are pregnant, because it has side effects such as abortion and stillbirth.”
HSA further gathered that it is not recommended to eat nzu because of the severe health risks, particularly the risk of heavy metal toxicity.
Calabash chalk has a negative relationship with maternal health and pregnancy outcome. It is crucial to contact a healthcare provider if you have consumed Nzu to get proper guidance and monitoring.
Health authorities have advised pregnant and breastfeeding women to avoid nzu due to its high levels of lead and arsenic.
