There are two theories as to why people age. One theory posits that aging is naturally programmed into the body. The second theory is that aging is the result of damage that has accumulated during life, which is why some people live longer than others.Know More
Everyone ages differently, and scientists believe that the rate at which someone ages comes down to four main things: chemistry, behavior, physiology and genetics. Studies have proven that when scientists adjust the genes in yeast cells, mice and other organisms, the life span of those creatures can be nearly doubled. It is believed that genetics makes up about 35 percent of a person's aging process.
Even with good genes, the body continues to undergo chemical changes throughout its life. Some of these changes cause damage to the body and are factors in the aging process. DNA repair, hormones, heat shock proteins and free radicals are all important concepts when looking at the biochemistry of aging.
As a person ages, certain organs in the body change. This includes the heart, which thickens over time. This thickening is due to a thickening of arteries. This gives the heart a much lower maximum pumping rate. As the immune system ages, it takes longer to replenish T cells. As a result, older people take longer to get over being sick.Learn more about Older Adults
As we age, our noses do tend to change shape and get bigger. Although the human nose doesn't actually continue growing with age, the cartilage found around the lower part of the nose weakens over time, causing the tip to droop because of the effects of gravity.Full Answer >
“Over the hill” is a subjective term meant to imply one is past one’s prime age. There is no specific age, although research suggests one is cognitively over the hill at 24.Full Answer >
In a normal, healthy adult, the resting pulse rate does not change much with age. Age does change the heart's ability to adjust to body activity; however, so it may take longer to get the heart pumping faster or slower during and after exercise. Normal pulse rate varies by person.Full Answer >
Vital capacity decreases with age due to physiological, anatomical and immunological changes that weaken the respiratory system over time. The lungs mature at age 20 to 25, and then progressively decline, according to a study published on the National Center for Biotechnology Information.Full Answer >