Solanidine is present in sera of healthy individuals and in amounts dependent on their dietary potato consumption.

Solanidine, a steroidal alkaloid, and its glycosides have been reported to have caused poisoning in man and animals. These alkaloids are normally present in small amounts in potatoes. Measurement of solanidine in body fluid would be expected to establish the real incidence of acute toxicity and help to resolve the question of any chronic toxicity including teratogenicity. We report the detection of solanidine in the serum of 57 normal healthy volunteer subjects in whom it measured 4.0-56.3 nmol/l (1.6-22.5 ng/ml) before the midday meal. There was a significant correlation between serum solanidine concentration and normal dietary intake of potato by the individual concerned. When two subjects abstained from potato and its products serum solanidine fell markedly and became minimal after the second week onwards.