It is thought that restricting feed intake in sows impairs welfare, but it is done to prevent excessive weight gains and to avoid reduced reproductive performance. This study combined the effects of feeding level with the presence of a foraging substrate and examined the gilts’ behavioural and physiological responses. Ninety-six individually housed gilts were assigned to one of four treatments: no substrate/restricted-feeding, no substrate/unrestricted-feeding, substrate/restricted-feeding and substrate/unrestricted-feeding. The substrate provided was wood chips. To measure feed intake, the amount of feed given to the unrestricted feeding treatments was measured. Body weights were measured at the beginning and end of the experiment to determine weight gains. At the same time, the gilts backfat thickness was measured using ultrasound. From week 8 to 12, observations were conducted to determine postures, chewing behaviours, pen and floor manipulations. Saliva samples were taken over a 24 h period during week 11. Urine samples were collected during weeks 2, 7 and 12 for analysis of adrenaline, noradrenaline and creatinine levels. Unrestricted-fed gilts had a higher feed intake, which led to higher body weight and larger increases in backfat thickness. Unrestricted-fed gilts had higher feed intake levels when a foraging substrate was provided. Unrestricted-fed gilts stood less and exhibited fewer oral behaviours. Gilts that were provided with a foraging substrate manipulated the floor twice as much than gilts without substrate. Gilts without substrate were observed to manipulate the pen and perform oral behaviour more frequently than those gilts with substrate. Feeding level and substrate provision did not affect adrenaline levels because the gilts were not exposed to any acute stressors. Cortisol and noradrenaline levels were lower in sow provided a foraging substrate. The authors concluded that unrestricted feeding is more effective in improving welfare, but in terms of stress, providing a foraging substrate may also improve welfare.