Low carb dieting causes accelerated aging. It increases cortisol and is highly catabolic.
You should read the articles on Ray Peat's site on tissues and aging; he explsins what nutrition has to do with it. In particular, he thinks carbon dioxide such as from sugar is protective and PUFAs (nuts, salmon, green vegetables) are bad.
You might track your morning temperature. If it is below 98, you are probably hypothyroid.
Retinoids and copper peptides are good to use to help build collagen. 1st generation copper peptides (ghk-cu) have been shown in studies to work faster than retinoids, and have fewer side effects, but they have some side effects ("copper peptide uglies") that occur with overuse.
Chemical peels are overly harsh and damage the skin. Instead of using acids, scrub your face a few times a week with a Clairisonic or use a microdermabrasion tool once a month. The PMD is getting a lot of good reviews on you tube.
I know about all of this because paleo/primal ruined my skin.