I would suggest a series of Skintyte treatments. These are laser light treatments that are painless and done in the office, usually in series of 5 or 6 treatments over several months. The laser stimulates the collagen to strengthen and the skin to tighten. Check out Skintyte before/after photos online. You'll be amazed.
I am a 40 year old physician who also is concerned about keeping my skin looking young and keeping that healthy glow. Eating correctly and drinking plenty of water are, of course, part of it. An appropriate skin care regimen is also key. But the thing that has helped me (and my patients) the most is ForeverYoung BBL. These are painless laser light treatments that rejuvenate dull skin and improve fine lines/wrinkles while bringing out that youthful glow. These have no downtime and are extremely affordable when compared to most aesthetic/cosmetic procedures. It's pretty amazing.