Lettuce is low in calories and has a high water content, which can be a hydrating treat for cats.
Risks
Lettuce should only be given occasionally and in small amounts to avoid disrupting the balance of nutrients in a cat's diet.
There is also a risk of pesticides or chemicals, so it should be washed thoroughly before offering it to cats.
Suggestions
Offer lettuce as an occasional treat in small quantities.
Ensure it is washed thoroughly to remove any pesticides or chemicals.
Note: even if labeled as safe, any food can potentially cause allergies. When introducing a new food, please feed a small amount and observe your cat for any allergic reactions.