One of the first changes in your body you may notice as you age is in its overall shape. Weight gain, shifts in how active you are (and therefore how muscular), chronically elevated levels of the stress hormone cortisol, as well as other hormonal changes, can all move fat to your midsection, leaving you looking apple-shaped (common for both older men and women).
Fortunately, not all changes in body shape are inevitable. Weight training, cardio exercise, healthy diet, and avoiding smoking can all help keep your abdomen -- and the rest of your body -- trim and youthful.
Time affects skin in two distinct ways: intrinsic aging, which is the result of cellular changes in skin cells over time -- and photoaging, which is the premature degradation of skin after years of sun exposure.
Intrinsic or chronological aging can be seen on skin that's never exposed to the sun. It includes thinning of the outer layer or epidermis, as well as thinning of the dermal layer beneath, leaving the skin more fragile and less elastic, and more prone to damage and wrinkling.
Photoaging, by contrast, can make the epidermis thicker, more rough, and leaves pores more visible. It also hastens the breakdown of collagen in the deeper layers of the skin, hastening wrinkles.
Staying out of the sun, and being diligent with high-SPF sunscreen can slow photoaging. Steer clear of tobacco and exposure to chemicals to keep skin healthy and young-looking.
If your hair doesn't seem to be growing as fast as it used to, or even where it used to, you're not alone. Changes on a microscopic or hormonal level can affect the hair follicle, slowing hair growth or eliminating it altogether, as in male-pattern baldness. Turning gray is one of the most universal changes in aging hair. Sometimes too much hair grows in areas it shouldn't, like on a woman's face or chest. This problem is called hirsutism.
Chemical and heat exposure from blow dryers, color treatments and even brushing can harm hair, leaving it rough and weathered.
Solutions range from temporary (conditioners, hair dyes, medications, tweezing and waxing), to permanent (hair transplants and electrolysis).
By the age of 40, a stiffening of the lens makes focusing on close objects more difficult. A yellowing of the lens may also block out certain wavelengths of light, affecting the body's circadian rhythm, or internal clock.
Age-related eye conditions, such as glaucoma, macular degeneration, and cataracts, can develop. More than half of people by the age of 80 will develop cataracts, according to the National Eye Institute. Ultraviolet light and tobacco use are believed to contribute to the development of cataracts.
Our sense of hearing depends on tiny hair cells within the ear that vibrate in the presence of sound. Over time, damage from environmental factors like exposure to loud noises, certain medications, and health conditions like high blood pressure and diabetes can all cause hearing loss.
An estimated 30 percent of people between the ages of 65 and 70 have some form of hearing loss, or presbycusis.
Prevent hearing loss by avoiding loud noises, especially ongoing and long-term exposure. Hearing aids are an effective remedy for a diminished sense of hearing.
Some older people hang on to their taste perception with little noticeable change. Others, especially those taking certain medications like antihistamines or antidepressants, may lose much of their sense of taste. Certain conditions, like Parkinson's, depression and diabetes, can also cause a loss or altering of taste.
Simple aging may account for being able to taste a lesser range of flavors, thanks to specialized taste receptors regenerating at a slower rate. Smell receptors in the nose may also stop turning over as rapidly, which can affect your sense of taste. In addition, certain medications and conditions like stroke and epilepsy, which affect how odors are perceived by the brain, may reduce your sense of smell - and taste.
Beating an estimated 100,000 times a day, this muscular pump delivers oxygen-rich blood to every part of your body. Over time, fat can build up in the arteries leading away from the heart, in a process called atherosclerosis, increasing blood pressure, and forcing this crucial organ to work harder.
Thin women of Caucasian or Asian ancestry are at greatest risk of developing thinning bones, according to the U.S. National Institute on Aging. Bone density loss can be prevented by eating a diet rich in vitamin D, calcium - especially up to the age of 30 when you're achieving peak bone mass, according to the National Institutes of Health - and doing regular weight-bearing exercise like resistance training and walking.
Even if you are diligent with dental hygiene, brushing and flossing daily, certain dietary factors can jeopardize the strength of your aging teeth. Acidic foods can thin teeth enamel, making it more vulnerable to breakage and erosion. Thinner enamel is also more translucent, which can reveal the yellowish dentin within the tooth. The result: yellowish, older-looking teeth.
The good news: a few simple techniques like rinsing with water immediately after eating acidic foods, and waiting 30 minutes before brushing, can keep your teeth white, strong, and looking younger.
Fingernails can be a kind of litmus test for your health in general, and they can change in texture, thickness, color and even shape, over time. Nutritional deficiencies, illnesses and simple wear and tear through exposure to harsh cleaning chemicals and dry air, can all weaken, and damage your nails.
Aging Bladder and Kidneys
Over time, kidneys become less efficient at clearing waste products from the blood. The capacity of the bladder to hold urine also diminishes, and different types of urinary incontinence, or leakage can occur, especially in women.
Certain behavioral techniques and medications like pelvic floor exercises, bladder training, and biofeedback, can improve bladder capacity.
Aging Under the Microscope. Public Information Booklet. U.S. National Institutes of Health, National Institute on Aging. Accessed February 22, 2012. http://www.nia.nih.gov/health/publication/biology-aging/aging-under-microscope