Nutrition also affects skill gain. When nutrition is higher than 50%, you get a bonus of 1% increased skill gain per 10% nutrition. For example, 65% nutrition would result in 1.5% extra skill gain, and 99% nutrition would result in 4.9% extra skill gain.
Loss of some amount of some random skills at death is unavoidable (aside from skills that have reached a level of 99+). However, fighting Fighting and skill characteristics will suffer losses in the event of any death, regardless of skill levels previously attained. The only way to prevent skill loss on death is to reach level 9 on the [[Path of knowledge]], which preserves all but fighting skill.