THE ASSOCIATION BETWEEN CASSAVA AND THE PARALYTIC DISEASE KONZO
There are three important objections to the cyanide hypothesis. First, cyanide exposure from other sources has not caused konzo. Second, tropical ataxic neuropathy (TAN), a different clinical entity, has also been attributed to chronic cyanide intoxication following consumption of cassava. Third, the association is found mostly in ecological studies or in studies on aggregated level, which considered to be of weak study design.
The evidence for the cyanide hypothesis, in an etiologic role, of high cyanogen intake from insufficiently processed cassava combined with low sulfur intake, is now strong enough to urge prevention, in the short term by promotion of efficient processing of cassava roots. According to this hypothesis, there are three prerequisites for the occurrence of konzo: a farming system dominated by bitter cassava, insufficient cassava processing and a protein deficient diet. However, the cyanide hypothesis has yet to be confirmed.