If I asked you about what natural changes took place in a person's body through their lifetime, most would respond with puberty and menopause. Did you know that if you lived to 82 years old, you would have gone through about 12 change? Medical science now states that it takes about 7 years for your body to switch out it proteins for new ones. I have observed that there are also physiological changes that accompany each shift. Some of these changes are subtle, and others are rather dramatic. Following is a list of some features of each 7th year epoch:
Age 7: Kids grow like weeds. It is about here that we see the change in kids faces from the rounded toddler years into the little-person stage with more well-defined features and voice change.
Age 14: Puberty. Straight forward enough: The boys get masculine and the girls get feminine. Moving on.
Age 21: This one can go unnoticed by most because for most it simply means going from looking teen-ish to looking twenty-something, but for some, changes that take place on par with puberty. Many find a new wave of achene. Girls often develop larger breasts at this stage. Guys often hit another growth spurt (this one hit Shaquille O'neal) and an increased sex drive (like they need that!), giving rise to the “his sexual peak” axiom. It is not as standard as puberty, but many will find it happened to them, or know someone whom it did.
Age 28: Again, for most this is just a shift in face from young twenty-something to late twenty-something. It is much more rare than the change at 21, but similar changes can happen here, though most of us will only get a few passing zits.
Age 35: Mid thirties. Not much here but more body hair (now thicker), less head hair (now thinner), and the realization that your music is now considered “Oldies-ish.”
Age 42: The usual changes in looks are now accompanied by changes in moods of the sexes. Women's sex drive sometimes increase, giving rise to the “her sexual peak” axiom. I'm not sure of the pronounced chemical change, but for guys, this is often when the piercing and the motorcycle come around. Loss of bone and hardening of the arteries should be in mind now – calcium for the ladies, and cut out the sodium for the guys. Also, you should keep a few pairs of reading glasses around the house, because your arms won't be long enough any more!
Age 49: For ladies, menopause sometimes starts here. The late starters on the mid-life-crisis in the guy camp often start here, but the major hormonal changes will be drawing to a close soon.
Age 56: If menopause is going to happen, now is the time! Her equipment is shutting down, but sometimes his is aswell (genetics and drinking factor in here heavily).
Age 63: Those who take care of their bodies through their lives will always stand out. This stage is sort of a big litmus test on that front. We will all run down in time, but here is when, if you took care of yourself, you will only see the gentle decrease of strengths and abilities as is natural in Maturing life. If drinking, smoking, and lack of sleep were sports you excelled in, then you are probably going to get old quick from this point (no, not Mature... just Old). The cells of your body have strained to keep you going this far, but they have had enough!
Age 70 and Beyond: Hormone levels tend to drop off from here on. Some seniors are spry and energetic while others have trouble doing day to day things… This is all a combination of genetics, personal choices, and luck of the draw.
I am no doctor, but I am observant. This idea is just a combination of things I’ve seen, combined with the few things I’ve read. Hopefully, I’ve hit some marks.