A study carried out by the Japanese Journal of Epidemiology has established concrete links between exposure to fluoride and uterine cancer (also known as endometrial cancer).

The relationship between fluoride concentration in drinking water and uterine cancer mortality rate was studied in 20 municipalities of Okinawa (a part of Japan that was under US control until 1972 and was fluoridated) and the data were analyzed using correlation and multivariate statistics. The research was published in a peer reviewed scientific journal. The Japanese Journal of Epidemiology.

Results demonstrated a significant positive correlation was found between fluoride concentration in drinking water and uterine cancer mortality in all 20 municipalities.

After controlling for confounding factors including socio-economic factors, the relationship between fluoride concentration and cancer mortality rates was considerable higher.

The report stated that "The uterine cancer mortality rate in the municipalities supplemented with fluoride at a concentration of 0.30 mg/1 (mean over 13 years) is 69.5% higher than that in the municipalities at zero fluoridation (water is artificially fluoridated to 0.8mg/L in Southern Ireland).."

"Uterine cancer mortality rate in fluoridated municipalities appears to have declined rapidly subsequent to cessation of fluoridation."

Uterine cancer is now the most common gynaecological malignancy in Europe and North America and accounts for 13% of all cancers in women and is most frequently found in women over the age of 50 following the menopause. Ireland alone has over 300 women diagnosed each year.

Ireland is the only country that has a legislative policy set by Government mandating that all citizens must consume fluoridated water.