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'Black' cooking oil can lead to male and female infertility

'Black' cooking oil can lead to male and female infertility

Doctors and health authorities in Taiwan are warning that consuming olive oil mixed with cottonseed oil introduces the phenolic aldehyde gossypol into the system, adding an organic compound which has been shown to cause reproductive toxicity and is even used as a male contraceptive in some countries. Once ingested, gossypol not only harms the internal organs, nervous system and reproductive system; sustained use can lead to testicular atrophy and decreased sperm motility and quantity in males, while females can suffer uterine atrophy and menstrual disorders. Medical experts note that refining processes and technology must be improved to remove gossypol from cottonseed oil and avoid such harmful results.

Tatung Foods is under fire for marketing what it called 100% extra virgin olive oil that has been found to be olive oil mixed other oils such as cottonseed oil, sunflower oil, copper chlorophyll and other additives. Prosecutors have obtained documents from company chairman Kao Chin-li with "exclusive recipes" containing formulas that call for anywhere from 20 to 40% cheap cottonseed oil. Company records show that over the past seven years a cumulative total of 10,000 tons of cottonseed oil has been imported for an average of about 1,500 tons a year.

Dr. Yan Tsung-hai, a nephrologist at Linkou Chang Gung Memorial Hospital, notes that cottonseed oil is extracted from cotton seed and that cotton seed contains gossypol. Gossypol is toxic, so the refining process must be carried out very carefully to ensure that gossypol is significantly reduced or removed completely.

Yan notes that gossypol is used as a male contraceptive in mainland China, Brazil, parts of Africa and other areas. The Chinese government stipulates that the gossypol content in cotton seed oil cannot exceed 0.02%.

Maw-sheng Lee, a respected authority on obstetrics and gynecology and infertility, points out that the World Health Organization (WHO) has long been studying gossypol and has determined that in a sample of men who consume one tablespoon or approximately 15cc of cottonseed oil daily for a year, 90% will be infertile.

Maw-sheng Lee explains that the WHO found China’s highest rate of male infertility in a district which produced cottonseed oil. Local residents consumed relatively large amounts of the oil over long periods, resulting in insufficient sperm motility in males.

Lee says that the average rate of infertility among men and women of marriageable age in Taiwan has remained fairly steady at about 15% over the past seven years. He says that the impact of consuming cottonseed oil in Tatung oil products – and possibly other food products as well – is hard to gauge, as the oil has been marketed all across the island and not in one particular area.