Alkylresorcinols (AR) are phenolic lipids found in high amounts in wholegrain wheat and rye. They may be important as bioactive components and/or biomarkers of wholegrain wheat and rye intake. AR absorption was studied with pigs during a habitual diet and after a single meal of AR-rich diet. In study 1, four pigs were fed wholegrain rye (RD) and white wheat bread (WD) for 1 week in a cross-over design. Arterial and venous AR concentrations were determined over 540min after feeding on days 5 and 7. In study 2, four pigs were fed a synthetic, starch-based diet for 5d, and arterial and venous AR concentrations were determined over 960min after feeding a single meal of RD. In study 1, plasma AR concentrations after consuming RD peaked at 120min, remained elevated between 120 and 420min, and were re-elevated on refeeding at 480min. In study 2, AR appeared in the plasma after 60min, peaked at 180–240min, and remained elevated after 960min. The apparent elimination half-life was 3·93h, and the maximum plasma concentration was 666 (sem 35) nmol/l. Arterial and venous plasma AR concentrations were similar, suggesting that AR are absorbed via the lymphatic system. AR concentrations in pig plasma increase rapidly after a meal containing AR, and persist in plasma for at least 5d, indicating that AR may be a useful biomarker of wholegrain wheat and rye intake.