aging(redirected from aging of fetuses)
Also found in: Dictionary, Thesaurus, Financial, Encyclopedia.
- Hearing, which declines especially in relation to the highest pitched tones.
- The proportion of fat to muscle, which may increase by as much as 30%. Typically, the total padding of body fat directly under the skin thins out and accumulates around the stomach. The ability to excrete fats is impaired, and therefore the storage of fats increases, including cholesterol and fat-soluble nutrients.
- The amount of water in the body decreases, which therefore decreases the absorption of water-soluble nutrients. Also, there is less saliva and other lubricating fluids.
- The liver and the kidneys cannot function as efficiently, thus affecting the elimination of wastes.
- A decrease in the ease of digestion, with a decrease in stomach acid production.
- A loss of muscle strength and coordination, with an accompanying loss of mobility, agility, and flexibility.
- A decline in sexual hormones and sexual functioning.
- A decrease in the sensations of taste and smell.
- Changes in the cardiovascular and respiratory systems, leading to decreased oxygen and nutrients throughout the body.
- Decreased functioning of the nervous system so that nerve impulses are not transmitted as efficiently, reflexes are not as sharp, and memory and learning are diminished.
- A decrease in bone strength and density.
- Hormone levels, which gradually decline. The thyroid and sexual hormones are particularly affected.
- Declining visual abilities. Age-related changes may lead to diseases such as macular degeneration.
- A compromised ability to produce vitamin D from sunlight.
- A reduction in protein formation leading to shrinkage in muscle mass and decreased bone formation, possibly leading to osteoporosis.
Causes and symptoms
- Programmed senescence, or aging clock, theory. The aging of the cells of each individual is programmed into the genes, and there is a preset number of possible rejuvenations in the life of a given cell. When cells die at a rate faster than they are replaced, organs do not function properly, and they are soon unable to maintain the functions necessary for life.
- Genetic theory. Human cells maintain their own seed of destruction at the level of the chromosomes.
- Connective tissue, or cross-linking theory. Changes in the make-up of the connective tissue alter the stability of body structures, causing a loss of elasticity and functioning, and leading to symptoms of aging.
- Free-radical theory. The most commonly held theory of aging, it is based on the fact that ongoing chemical reactions of the cells produce free radicals. In the presence of oxygen, these free radicals cause the cells of the body to break down. As time goes on, more cells die or lose the ability to function, and the body soon ceases to function as a whole.
- Immunological theory. There are changes in the immune system as it begins to wear out, and the body is more prone to infections and tissue damage, which may finally cause death. Also, as the system breaks down, the body is more apt to have autoimmune reactions, in which the body's own cells are mistaken for foreign material and are destroyed or damaged by the immune system.
- diminished or lack of desire for food
- increasing confusion
- failure to thrive
- urinary incontinence
- weight loss
- Vitamin E, 400-1,000 IUs daily. Protects cell membranes against damage. It shows promise in prevention against heart disease, and Alzheimer's and Parkinson's diseases.
- Selenium, 50 mg taken twice daily. Research suggests that selenium may play a role in reducing the risk of cancer.
- Beta-carotene, 25,000-40,000 IUs daily. May help in treating cancer, colds and flu, arthritis, and immune support.
- Vitamin C, 1,000-2,000 mg per day. It may cause diarrhea in large doses. If this occurs, however, all that is needed is a decrease in the dosage.
- B12/B-complex vitamins, studies show that B12 may help reduce mental symptoms, such as confusion, memory loss, and depression.
- Coenzyme Q10 may be helpful in treating heart disease, as up to three-quarters cardiac patients have been found to be lacking in this heart enzyme.
aging/ag·ing/ (āj´ing) the gradual structural changes that occur with the passage of time, that are not due to disease or accident, and that eventually lead to death.
AgeingDermatology Changes in the skin and subcutaneous tissues associated with growing older. Ageing effects (e.g., patchy hyperpigmentation, fine wrinkles, telangiectasias) result from intrinsic and extrinsic processes and reflect the physicaleffects of the passage of time. Ageing skin is usually associated with a sagging face, in which deeper tissues (i.e., subjacent soft tissue) and structural landmarks lose their resiliency.
Geriatrics A multifaceted process in which bodily structures and functions undergo a negative deviation from the optimum. Ageing phenomena include decreases in memory, muscle strength, muscle mass, manual dexterity, cardiac output, and auditory and visual acuity, as well as loss or thinning of hair. Other ageing phenomena include increased body fat, and increased risk of cancer, diabetes, infections, osteoarthritis, and osteoporosis accompanied by a decrease in height due to decreased intervertebral space.
Intrinsic ageing The immutable effects of chronologic ageing, e.g., atrophy-attenuation of epidermis, retraction of rete pegs, decreased number of Langerhans’ cells and melanocytes, general decay of structural dermal and epidermal components
Extrinsic ageing Effects of external factors, e.g., sunlight, smoking, gravity and gravidity, keratinocytic dysplasia, solar elastosis, and possibly carcinogenesis; intrinsic & extrinsic ageing are intimately linked and thus not divided
Inevitable & immutable Cataracts, decreased skin elasticity, farsightedness, fibrous replacement of muscle, greying, poor recall, slowed intestinal transit, prostatic hypertrophy, wrinkling
Inevitable but modifiable Baldness, cancer, reduced cardiac reserve, slow erection and ejaculation, decreased hearing, immunity, and vision, increased weight, liver spots (age spots), osteoporosis, decreased short-term memory, decreased stamina
agingA multifaceted process in which bodily structures and functions undergo a negative deviation from the optimum; aging phenomena include ↓ memory, muscle strength and mass, manual dexterity, cardiac output, auditory and visual acuity, loss or thinning of hair, ↑ body fat, ↑ risk of CA, DM, infections, osteoarthritis, osteoporosis accompanied by ↓ in height due to ↓ intervertebral space. See Geriatrics, Life-extending diet Dermatology Changes in the skin and subcutaneous tissues of those whose future is shorter than their past; aging effects result from intrinsic and extrinsic processes See Aging, Aging skin, Sagging face.
Patient discussion about aging
Q. I would like to know the best age for pregnancy? Hi I am Deontae; I got married before 1 year. I and my wife planned to have a baby after 3 years. But now she is 25. I would like to know the best age for pregnancy? Which will help us to change our plan?
so if your wife is now 25, i think you guys still have another 5-10 years to "accomplish" your family plan, hehehe...
Good luck, and stay healthy always..
Q. when is the most common age to get any kind of cancer? is there is such age?
Q. Does eyesight always decrease with age? I am 45 years old and never had glasses. All my friends are starting to wear reading glasses. Should I expect this too?