The major source of human nitrate exposure comes from vegetables and drinking water. Several studies were performed to estimate the total daily dietary nitrate intake. However, only nitrate that is absorbed from the gastro-intestinal tract may contribute to the toxicity of nitrate in the body. At present no data are available on the bioavailability of nitrate from vegetables. A low bioavailability of nitrate from vegetables may have implications for the risk analyses of nitrate exposure. The present experiment was carried out to study the feasibility of a healthy volunteer study on the bioavailability of nitrate from vegetables. The procedures for the preparation of beetroot, lettuce and spinach were studied. Secondly, plasma samples were drawn from 6 adult volunteers after administration of a single oral dose of either 300 gram beetroot (573 mg nitrate), 300 gram lettuce (742 mg nitrate) or 300 gram spinach (537 mg nitrate). This study demonstrates that the nitrate in all three vegetables is rapidly absorbed from the gastro-intestinal tract. Maximum plasma nitrate concentrations, ranging between 21.3 and 43.7 mg/kg, were reached after 1 to 1.5 hours.