This paper investigates a suspected outbreak of beri-beri which occurred in The Gambia in 1988. The outbreak was spatially specific and had a distinct age and gender bias, with young men aged 15-49 being the group mainly affected. The age and gender bias of the outbreak is particularly interesting as women and children in the developing world are usually more susceptable to conditions associated with malnourishment, than men. The authors investigate the peculiar nature of the outbreak and find that they cannot easily explain the apparent age and gender bias. The authors note that at the time of the outbreak medical treatment took precedence over socio-economic investigations. This makes it difficult to ascertain why certain age and gender groups were affected and thus to target them for future preventative health education programmes. This case study therefore concludes, that where possible, medical investigations must be combined with socio-economic studies if future outbreaks of this kind are to be avoided.