What is the best product to Regenerate college and in your face
Your safest bet for supporting collagen production in skin are retioids: tretinoin (https://whatsinmyjar.com/skincare-ingredients/tretinoin), retinol (https://whatsinmyjar.com/skincare-ingredients/retinol), retinal (https://whatsinmyjar.com/skincare-ingredients/retinal), retinyl retinoate (https://whatsinmyjar.com/skincare-ingredients/retinyl-retinoate).
Vitamin C (https://whatsinmyjar.com/skincare-ingredients/ascorbic-acid) has been also shown to help thicken collagen in skin.
Regular use of glycolic acid can also help (https://whatsinmyjar.com/skincare-ingredients/glycolic-acid).
What would you recommend for supporting collagen to people with rosacea and /or very sensitive skin
Sunscreen is the #1 product for sure.
Vitamin C is usually tolerated better than retinoids, so you can try a minimalist serum with ascorbic acid (for example https://whatsinmyjar.com/product/goldfaden-md-brightening-elixir, https://whatsinmyjar.com/product/cerave-skin-renewing-vitamin-c-serum, or https://whatsinmyjar.com/product/paulas-choice-c15-super-booster).
Retinoids are also not off limits - it is possible for a rosacea-prone skin to tolerate them (varies from person to person of course). I wrote about starting a retinoid for sensitive skin here: https://whatsinmyjar.com/entries/93/how-to-start-with-a-retinoid-if-you-have-sensitive-skin.
Hope this helps!
Thank you so much. I'll have a look at your suggestions.