Chinese researchers in the 1960s found that cooking with crude cottonseed oil resulted in
male infertility. Studies indicated that the gossypol could influence the testis directly and
caused azoospermia or oligozoospermia (Dai et al., 1978; Xue, 1980; Xue, 1985). Side effects
associated with long-term use of gossypol (up to six years) resulted in hypokalemic paralysis
(0.75%) and irreversible infertility (9.9%) (Xue, 1980; Xue, 1985).