Negative effects of oral fatty acid supplementation on sweat chloride in cystic fibrosis.

Essential fatty acid supplementation with oral safflower oil (1 gm/kg/day) to 11 cystic fibrosis patients (aged 6 months to 14 years) for one year produced no significant change in sweat chloride concentration (mEq/liter) or sweat rate (gm/min/m2), Addition of vitamin E (10 mg/kg/day) to the safflower oil had no effect on sweat chloride concentration or rate compared to placebo. No clinical improvement could be detected compared to a control group. These results do not support previous reports of the effects of fatty acid supplementation on sweat electrolyte concentrations in cystic fibrosis.