Lupanine is one of the toxic quinolizidine alkaloids present in lupins, the bitter nitrogen-containing compounds that defend the plant against pests. In bitter lupin varieties it makes the seeds unpalatable and mildly poisonous, causing nausea, vomiting, dizziness and other symptoms if eaten in quantity. Food use therefore depends on low-alkaloid sweet lupin varieties, bred to contain only traces of lupanine and related alkaloids, and on debittering treatments — soaking, boiling and repeated water changes — that leach the water-soluble alkaloids from the seeds. Regulatory limits cap total alkaloid levels in lupin foods, and processors verify compliance by chromatographic analysis of raw materials and finished products.