No, there's no need to peel cucumber before putting it into dishes or eating as long as you're going to be cooking them with the skin on. Peeling will reduce some nutrients but it won't make too big of a difference overall since they both contain high amounts of water and fiber which are good for weight loss. However, peeling might be necessary depending on what type of recipe you're making. Peeling also reduces the number of calories present in a cucumber but the difference is rather negligible. Some people also choose to peel cucumbers before eating them raw because the skin can be a bit tough and chewy which makes it harder for your teeth to break down. Again, this is more of personal preference rather than an actual necessary step!