The Ethiopian Rift Valley has 14 million residents affected by excess fluoride (F). Adamitulu is particularly affected by fluorosis. The low intake of calcium may be a factor in the severity of fluorosis.
An 8 day trial was conducted to determine effects of dietary calcium on urinary F concentration. 28 healthy women were put into the following groups; Control (C), Milk (Mi), Moringa (Mo), Calcium supplement (CS). Groups Ca, Mo, Mi received ~ 300 mg Ca/day. Each morning subjects collected a urine sample for F excretion. Ethical clearance was obtained from Ethiopian Public Health Institute (EPHI).
Urine F (mg/L) over the 8 days was: C 12.2±1.5a, Mi 10.1±0.9b, Mo 8.3±2.1c, CS 8.6±2.1c (values with different letters, P<0.05). The C group shows the typically high F excretion of residents, where water F exceeds WHO upper limit of 1.5 mg/L F. Milk lowered F concentration by almost 20%; however moringa and the CS lowered F concentration by 30%.
Lower F excretion is an indicator of poorer absorption, as we have shown in F balance studies of rats (Kebede et al, Int J Bioch Res Rev10:1-8, 2016). With less absorption, the F burden in the body is lower, and severity of fluorosis is lessened. The effect of diet in fluorosis has been shown in epidemiological studies but our trial and animal study together indicate a direct role of diet on F and therefore the potential of diet to mitigate fluorosis.