Raising the zinc status

Forty years after beginning her research career in Ethiopia, Human Nutrition Professor Rosalind Gibson has returned to the south of that country to work among some of the many people in sub-Saharan Africa who have a nutritional status particularly low in zinc.

Zinc is vital for growth, immune competence and neuro-behavioural functions. It is important for pregnant women who, without sufficient zinc, run increased risk of early labour, low-birth-weight babies and poor neonatal health resulting in increased child morbidity.

Gibson says the average requirement for zinc for pregnant women in this setting is 12mg, but the intake averages 5mg due to a unique diet, heavily dependent on the native false banana, enset (low in zinc), and maize (high in phytate, preventing the absorption of zinc).

Very little, if any, animal-source food is consumed and most is sold for cash. However, there are some upsides to this diet - bacteria produce folate and vitamin B12 during enset fermentation, and iron from soil contaminates the food and is probably absorbed.

A founding member of the International Zinc Nutrition Consultative Group, Gibson says zinc is now attracting the attention of the World Health Organisation.

A number of interventions are planned to improve maternal health and birth outcomes among these people - zinc supplementation for women before, during and after pregnancy, programmes encouraging dietary diversification (particularly the consumption of animal protein) and the biofortification of crops with zinc.

This research is a collaboration among the University of Otago, Hawassa University (Ethiopia), University of Colorado Health Sciences Centre and Oklahoma State University, and has attracted funding from the US National Institute of Health.