did keto for a month, i would say yes i feel lighter, the first few days you can see you are getting slimmer because losing body water, thus you need to take salt (healthier salt)

but there is the bad side of it which is you will have keto flu for the first few weeks, you need to eat more salt, and if you would stick for the strict one, 20gram of carbs per day....depends on your preference.

I know some cancer survivor practice this diet because cancer cells can't live without glucose.