The energy confinement time for ohmically heated discharges in the FT (Frascati, Italy) tokamak was studied in a wide range of plasma parameters. It was found to increase linearly with the line averaged density below a value of 1x10/sup 14/ per cubic centimeter and to saturate at higher densities. Analysis of the experimental data showed that, at the same density at which saturation was reached, the effective charge state became nearly equal to 1, and the electron and ion temperatures became nearly equal. The saturated energy confinement time showed a strong isotope effect with a reduction factor of 1.5 when operating in hydrogen. The sawtooth period was closely correlated with energy confinement time and displayed the same saturated behaviour and isotope effect. The ion thermal diffusivity was found to be compatible with neoclassical theory up to the maximum density, but a neoclassical multiplier of 3 would only fit the highest line averaged density data. The electron thermal diffusivity first decreased with the inverse of line averaged density, but remained nearly constant in the saturated region. Therefore, ohmic saturation in the FT seems to be primarily caused by electron transport.