Lucky for you, I made a very high tech and involved chart that shows you why humans age and turn into wrinkled little prunes.
I can tell that you are very impressed with my Photoshop skills! I drew that myself. (Ok, I drew the sun, the rest was just cut and paste!)
Really, there are some more definable things that make us look older. Here are the structural things that happen as we age, resulting in sagging and wrinkles.
2. Changes in the Skin
3. Bone Structure Changes
Notice that the changes in your skin are last aren't always the most prominent, though we all do tend to focus on our skin. Trust me, if the other two are out of whack, you're not going to be worrying about a couple of crow's feet!
When the fat isn't right, the problems are really easy to find. Basically, the current thinking is that in your face there are pockets of fat. Some of them are pretty much always there and will only start to go away with part of the aging process (this loss starts in your 30s for most people but is highly variable due to genetics). These pockets are deep and help provide structure, think deep in your cheeks or under your eyes. Some pockets are a bit more superficial and are more easily affected by weight fluctuations, but will also affect the overall appearance of your face/neck.
What are the results of changes in these fat pockets? If you've lost the fat, you might have sunken cheeks or increased hollows under your eyes (talk about dark circles!). Too much fat can be just as bad (and realize that when most of us gain weight, some of it does go to the bottom half of our face) resulting in a double chin, ill defined jaw line (or if there's enough on the neck, the dreaded turkey neck!) and can also make under eye bags bigger.
So, how to avoid these problems? Maintain a steady and healthy weight.
I do not mean being model thin (I've been backstage at Fashion Week, the girls are very scary in person. Please don't do that!)
I mean a healthy Body Mass Index. aka the BMI. Granted, the BMI is not for everyone (most notable are the large very musclar guys in the NFL, their muscle throws the whole thing off), but it works for all of us "normal" people. Back in the day when I was in primary care (oh, the days of vaccines and discussions about developmental milestones...) calculating BMI was something I did for every patient. It was plotted on a little growth chart, and if a kid was about 75% or higher it resulted in a discussion about portion control, increased veggies and decreased soda and Flaming Red Hot Cheeto intake. (The kids in So Cal are obsessed with that flavor of Cheetos and eating at least 1 large bag was universal amongst our patient population. Eat too many and they turn your poo red. Really.) Anyways, I hope your doctor calculates your BMI for you at your visits, and if not ask for it to be done.
To figure out what your BMI is on your own, there's a great BMI calculator from the National Heart, Lung and Blood Institute. Be honest and use the actual numbers of your weight and height, not the ones that you tell friends and family! Most likely you'll be surprised by where you fall in the curve. (I'm in the mid-range of healthy at 21.4, by the way.)
The way to make those fat pockets cause even more issues is to have massive weight fluctuations. Yes, if you are 800 pounds and can not leave bed, I agree you need to lose a lot of weight. But constantly yo yo dieting off the same 10-20 pounds is likely not going to help. I know Oprah has done it, but most of us aren't so lucky.
Obviously, a good plastic surgeon or cosmetic dermatologist can move fat around or use an injectable to fight these effects. That's not my specialty, so I'll just say find a good one if you're thinking about one of those options.
As we grow older, the skin definitely changes. It's repair functions slow down really in your 30s, you have less collagen and elastin production also in your 30s (read my post on The Dermis to know why this is bad, you lose both structure and elasticity in the skin). These issues are exaggerated when skin is dry, well moisturized skin kind of "plumps up" and helps hide this a bit, at least temporarily. After menopause it all just gets worse, unfortunately. Decreased hormone levels lead to even more lose of elasticity, skin is thinner and drier.
Obviously, these are the things that I'll be addressing the most in my posts. Overall the goal is to increase collagen and elastin production, keep up cell turnover (which also helps with increased collagen and elastin production), moisturize the skin and keep the overall tone and texture of skin even. Some of the ingredient categories that help achieve these goals are Retinoids, Anti-Oxidants, and Peptides, just to name a few.
Bone Structure Changes
With age, everyone's bones will lose some mass. And while there does seem to be a little bit of debate about how much this affects aging. I've seen a lot of quotes from different plastic surgeons, some put a lot of stock in this, some say that if there are bony changes with age, especially after menopause, then you should only expect bones to change at the most a millimeter.
So, should you do anything about bony changes? Probably not much more than you would do to combat bone loss in the rest of your body. That means keeping up your calcium intake (either via diet or supplements), some level of physical activity and talking to your doctor about other options if needed.