Older adults are wise, resilient, and spend most of their lives free of disabilities. However, many physical and mental conditions can accompany the aging process. With a comprehensive geriatric assessment and maintenance of a healthy lifestyle, these conditions are managed so that older persons can continue with their daily activities. Later life provides many opportunities for social interaction, participation in activities, continued employment, volunteerism, and leisure pursuits. These opportunities are different for each person because resources vary. There are older persons who will have the ability to retire, while others will continue to work. Time, income, interest, and health will determine the extent to which each older person is able to take advantage of various opportunities. Promotion and adherence to a healthy lifestyle that includes a good diet, adequate rest, exercise, engagement in meaningful activities, and a connection to others is critical at all stages of the life cycle.
Many transitions occur throughout the life course. Most are managed with little effort, while others require the assistance of professionals. Professional counselors have an opportunity to position themselves to provide advocacy, referral, counseling, and educational services to a growing older population.
Biological Theories Associated With Aging
Numerous theories have been identified to explain why the human body ages, as there is no single theory that can do so. Each theory provides insight into certain aspects of aging, and a firm grasp of these concepts will help mental health professionals better understand their older clients and the aging process.
Neuroendocrine Theory
The neuroendocrine theory of aging focuses on the neuroendocrine system, which is a complicated network of biochemicals that govern the release of hormones altered by the hypothalamus located in the brain. The hypothalamus controls various chain reactions to instruct other organs and glands to release their hormones. The hypothalamus also responds to the body hormone levels as a guide to the overall normal activity, and as we grow older, the hypothalamus loses its precision regulatory ability, and the receptors that uptake individual hormones become less sensitive to them. Additionally, as we age, the secretion of many hormones decline, and their effectiveness is also reduced (Ramaswamy, 2012). As the body ages, it produces lower levels of hormones that are vital for well-being. Dehydroepiandrosterone (DHEA) is a hormone that comes from the adrenal gland and also made in the brain. DHEA leads to the production of male and female sex hormones. DHEA levels begin to decrease after age 30 and levels decrease more quickly in women. Lower DHEA levels are found in people with hormonal disorders, HIV/AIDS, Alzheimer’s disease, heart disease, depression, diabetes inflammation, immune disorders, and osteoporosis (Mayo Clinic, 2015). DHEA may cause side effects related to other hormones, and women may experience symptoms such as increased unnatural hair growth and deep voice, and men may experience urinary urgency and aggression, among other symptoms. Other side effects that may occur in either sex include sleep problems, headache, nausea, skin itching, and mood changes; and DHEA may affect levels of other hormones such as insulin (hormone that controls the glucose levels in the blood) (Mayo Clinic, 2015). Melatonin is another hormone and has been called the antistress hormone due to its ability to regulate rhythms of other hormones and its ability to blunt the negative effects of cortisol. Cortisol is a hormone that regulates a wide range of processes throughout the body including metabolism and the immune response. It also has a very important role in helping the body respond to stress; however, when cortisol levels are elevated longer than normal, it contributes to illnesses and diseases because cortisol is considered the stress hormone when it is elevated. A decline in human growth hormone results in changes in body composition. Lean body mass shrinks, and there is an increase in adipose (fatty) tissue. This loss of lean body mass leads to atrophy, or wasting away, of skin, skeletal muscle, and bone. Decreased levels of human growth hormone can also lead to elevated cholesterol levels (Park et al., 2011).
The neuroendocrine theory proposes that the most effective approaches to delay (and even reverse) the aging process and ameliorate the diseases of aging is to restore hypothalamic (and peripheral) receptor sensitivity, restore hormone levels to more youthful values by hormone replacement therapy, prevent damage effects of hormones, and restore intracellular bioenergetics (energy transfers in living cells). This theory explains the cause of major diseases of aging, which contribute to over 85% of deaths and disabilities of middle-aged and elderly individuals. These diseases include obesity, atherosclerosis, hypertension, diabetes, and cancer among others (Dean, 2012).
Autoimmune Theory of Aging
The autoimmune theory of aging proposes that protective immune reactions decline with age, as the body becomes less capable of producing sufficient antibodies (Bengtson, Putney, & Johnson, 2005). According to this theory, aging is attributed to the decline of the body’s immunological system. Studies indicate that as individuals age, the body’s ability to produce necessary antibodies declines and immune systems become less effective in fighting disease (Bengtson et al., 2005). At the same time, the white blood cells active in immune response become less able to recognize foreign invaders and are more likely to mistakenly attack the body’s own proteins. For example, one hypothesis proposes that cancer rates are higher in older people because the immune system’s surveillance mechanism may not recognize and destroy precancerous cells as it does in younger individuals (Bengtson et al., 2005).
Additionally, the aging immune system mistakenly produces antibodies against normal body proteins, leading to a loss of self-recognition. An example of this is rheumatoid arthritis, in which the immune system attacks the joints, particularly the hands, wrists, feet, ankles, and knees. While a decline in immune system functioning causes disease, there is no evidence to suggest that a less efficient immune system causes aging (Hayflick, 1996). This theory is unable to account for the mechanism of biological aging, the progressive generalized impairment of functioning that occurs as people grow older. However, the autoimmune theory is another theory that attempts to explain why diseases occur. Its basic premise is that immune reactions normally directed against disease-producing organisms as well as foreign proteins or tissue begin to attack cells of the individual’s own body.
Free Radical Theory of Aging
The free radical theory of aging explains the basic chemical process underlying aging. The reaction of active free radicals, normally produced in the organisms, with cellular constituents initiates the changes associated with aging (Herman, 2006). The free radical theory of aging suggests that free radicals, or unstable molecules, are produced when the body transforms food into chemical energy, creating damage that causes aging. This transformation occurs at the individual cell level. Free radicals also may be generated in the body due to cigarette smoke, drugs, and radiation (Dietrich & Horvath, 2010) and are a by-product of normal cells. Most changes associated with aging result from damage caused by free radicals (Bengtson et al., 2005). Free radicals disrupt the normal production of DNA and RNA and alter the lipids, or fats, in cell membranes. They also damage cells lining blood vessels and interfere with the production of prostaglandins, which are derived from essential fatty acids and regulate many physiological functions. Partly as a result of free radical damage, aging leads to alteration of proteins (cross-linking). The prematurely aged, wrinkled skin of smokers is caused by free radical-induced damage that smoking engenders, and cataracts have been linked to free-radical exposure (de Magalhaes, 2014). Free radicals have also been associated with dementia, cancer, and heart disease. Combating free radicals requires the consumption of antioxidants, which can be obtained through food.