Lifestyles and Health
Reading
Curtis, A.J., Health Psychology,
Routledge, 2000, Chapter 7.
Psychosocial
mediators of health
Lifestyle and health
About 50% of premature deaths in western countries can be attributable to lifestyle. Smokers, on average, reduce their life expectancy by five years, individuals who lead a secondary livestock by two to three years. Four behaviours in particular are associated with disease: smoking, alcohol misuse, poor nutrition and lower levels of exercise; these are called the “holy four”. Conversely, rarely eating between meals, sleeping for seven to eight hours each night, and eating breakfast nearly every day have been associated with good health and longevity (Breslow and Enstrom 1980). Recently high-risk sexual activity has been added to the risk factor list.
In this country saturated fatty acids, full fat milk and red meat are being replaced with low saturated fats, semi skimmed milk and white meat.
We are being encouraged to reduce our intake of harmful substances (e.g. smoking and alcohol).
About 50% of premature deaths in western countries can be attributed to lifestyle (Hamburg et al., 1982). Smokers, on average, reduce their life expectancy by five years and individuals who lead a sedentary (i.e. none active) lifestyle by two to three years (Bennett and Murphy, 1997).
With lifestyles, we consider a whole pattern of behaviours that may be tied into the type of job that an individual has, the culture and sub culture they feel part of, and people they live with (Banyard 1996).
Belloc and Breslow (1972) conducted an epidemiological study asking a representative sample of 6928 residents of Almeida County, California whether they engaged in the following seven health practises:
- sleeping seven to eight hours daily
- eating breakfast almost every day
- never or rarely eating between meals
- currently being at or near prescribed height adjusted weight
- never smoking cigarettes
- moderate or no use of alcohol
- regular physical activity.
Good health practice is associated with positive health status and this association was independent of age, sex and economic status (Belloc & Breslow, 1972). Follow-up studies after five and half years and nine and half years showed that good health practice is associated with longevity.
Men who followed all seven of these health practises had a mortality rate that was only 28% of that for men who followed three or less of these practises. For women, the difference was smaller: mortality rates for those who followed all seven practises was only 43% of that for women who followed three or less practises.
Poverty and health
1.
Those in the
lower classes have more stresses in the form of daily hassles (Myers et al
1974).
2.
The less well off
have fewer resources to mediate these stressors, and therefore less control
over their environment. Lack of control
being a source of stress (see stress notes).
3.
Social support is
less available to those in the lower social classes (Adler et al. 1994)
Overall it is the relative poverty
that matters. People in Cuba are poor,
but enjoy good health, because they are nearly all equally poor (Wilkinson
1992).
Ethnicity and Health
In the USA, Blacks suffer more from
heart disease, cancer, liver disease, diabetes and pneumonia. They are also more likely to die from
violence (Markides 1983). In Britain
CHD amongst male Asians is 36% higher than the national average, and is 46%
higher for Asian women. The difference
was most marked for Asians between the ages of 20 and 39 years; CHD rates were
two to three times higher than whites (Balarajan and Raleigh 1993). For British Afro-Caribbeans the incidence of
strokes amongst men is 76% higher than the national average and 110% higher for
Afro-Caribbean women. Mortality through
hypertension is four times higher than the national average, and seven times
higher for Afro-Caribbean women. Cancer
rates have been lower amongst Afro-Caribbeans, but is now rising (Barker and
Baker 1990).
There are also differences in health
behaviour. American Black women smoke
less and drink less than white women (Gottlieb and Green 1987). In the UK few women from ethnic minority
groups smoke. Amongst men
alcohol-related morbidity is high for Asians of Punjabi origin.
Gender and Health
Women live longer than
men. In the eighties the average life
expectancy for men was 71 years and 77 years for women. Paradoxically men consult their doctor less
than women and experience fewer life threatening acute illnesses. Biological explanations for this difference
point to the role of Oestrogen, that reduces blood clotting and cholesterol
levels, whereas testosterone increases clotting (McGill and Stern 1979). Men respond to stresses in a way that is
biologically more dangerous than it is for women. They show, under laboratory conditions, greater stress hormone
levels, blood pressure and cholesterol levels, than women. However, these differences are in part due
to cultural factors. Women who take on
traditionally male stressful jobs tend to exhibit similar biological responses
as men (Lundberg et al, 1981). Men are more likely to be overweight, smoke
more frequently cigarettes containing higher levels of nicotine and tar, eat
less healthily and drink more heavily than women (Reddy et al. 1992). They are more likely to work in unhealthy
environments and be subjected to a greater risk of accidents.
By the beginning of 1992, nearly two and a half million people had died of AIDS worldwide and 19 and a half million were known to be HIV positive. UK figures indicate a marked increase in the prevalence of other sexually transmitted diseases and unwanted pregnancies. There is evidence of the higher prevalence of un-safe sex practice is and perhaps harrowing future increases of HIV infection and AIDS. Adolescents heterosexuals form an increasingly at risk group for AIDS, accounting for about 20% of all newly reported cases in the USA (Stiff et al. 1990). Young women and ethnic minorities appeared to be at particular risk. AIDS related illnesses form the leading cause of death for young women aged 25 to 34 in the USA and the third leading cause for those between 15 and 19 years old. Ethnic minority adolescents, the majority of whom were poor urban blacks, accounted for 53% of new AIDS cases. A similar picture is emerging in the UK. Although the majority of newly diagnosed cases of AIDS are still gay and bisexual men, the incidence of new cases among this group is falling slowly as the incidence of such cases among the heterosexual community rises more rapidly. Adolescent sexual behaviour places many at high risk for disease, as they are a highly sexually active group. The findings from a British survey, for example, revealed that nearly half adolescents aged between 16 and 17 have had at least one sexual partner during the previous year. However, they are unlikely to plan intercourse and only half use any form of contraception. Hawkins et al. (1995) reported that the most frequent safer sex behaviour amongst well-educated heterosexual students was the use of the contraceptive pill. The least frequent sexual practice, reported by only 24% of the sample, was the use of condoms. An important factor is that the majority of young persons do not see themselves as at risk of HIV infection or have feelings of invulnerability towards the disease.
Physical exercise
Exercise
Those who are physically active throughout the adult life live longer than those who are sedentary. Paffenburger et al (1986) monitored leisure time activity in a cohort of 17000 Harvard graduates dating back to 1916. Using questionnaires it was found that those who were least active after graduation had a 64% increased risk of heart attack compared with their more energetic classmates. Those who expended more than 2000 calories of energy in active leisure activities per week lived, on average, two and a half years longer than those classified as inactive. Exercise is protective against both chronic heart disease and some cancers (Blair et al 1986). How of this protection is achieved, whether through short intends periods of exercise or longer more frequent less intends periods appears irrelevant and no additional health gain is achieved by exceeding these limits.
About a quarter of the UK population engage in health promoting levels of exercise, with a similar picture in the USA. In recent years these levels have dramatically increased. For example in Wales 20% of men and 2% of women took sufficient exercise in 1985 but by 1990 this had increased to 27% of the population. Those who engage in exercise are more likely to be young, male and well-educated adults, members of higher socio-economic groups, and those who have exercised in the past. Those least likely to exercise tend to be in the lower socio-economic groups, older individuals, and those whose health is likely to be at risk as a consequence of being overweight and smoking cigarettes (Dishman 1982). Obstacles to exercise include not having enough time, lack of support from family or friends and perceived incapacity due to ageing.
Brannon & Feist (1997) describe five different types of exercise.
- Isometric exercise involves pushing the muscles hard against each other or against an immovable object. The exercise strengthens muscle groups but is not effective for overall conditioning.
- Isotonic exercise involves the contraction of muscles and the movement of joints, as in weight lifting. Muscle strength and endurance may be improved but the general improvement is in body appearance rather than improving fitness and health.
- Isokinetic exercise uses specialised equipment that requires exertion for lifting and additional effort to return to the starting position. This exercise is more effective than both isometric and isotonic exercise and promotes muscle strength and muscle endurance (Pipes and Wilmore, 1975).
- Anaerobic exercise involves short, intensive bursts of energy without an increased amount of oxygen such as in short distance running. Such exercises improve speed and endurance but do not increase the fitness of the coronary and respiratory systems and indeed may be dangerous for people with coronary heart disease.
- Aerobic exercise requires dramatically increased oxygen consumption over an extended period of time such as in jogging, walking, dancing, rope skipping, swimming and cycling. The heart rate must be in a certain range which is computed from a formula based on age and the maximum possible heart rate. The heart rate should stay at this elevated level for at least 12 minutes, and preferably 15 to 30 minutes. This exercise improves the respiratory system and the coronary system. It is best to have a medical examination before starting a programme of aerobic exercise and an electrocardiogram (ECG) can detect abnormal cardiac activity during exercise.
Overall fitness includes measures of muscle strength, muscle endurance, flexibility and cardiovascular (aerobic) fitness. Each of the five types of exercise described above contributes to these different types of fitness although no one type of exercise fulfils all of these requirements.
Kuntzleman (1978)
- Organic fitness-our capacity for action and movement determined by inherent factors such as genes, age and health status.
- Dynamic fitness-determined by our experience.
Exercise helps to control our weight and improve our body composition by increasing our muscle tissue. This improves the ratio of fat to muscle for our bodies and helps us to sculptor a more ideal body. Exercise is at least as good as dieting if not better. Exercising retains more leaner muscle tissue whilst dieting loses both fat and lean tissue.
Exercise protects against coronary heart disease (C. H. D.).Cooper (1982) maintains that aerobic exercise should be performed at 70 to 85% of maximal heart rate non-stop for at least 12 minutes three times per week in order to improve cardiovascular system fitness.
Lakka et al. (1994) conducted a large scale five-year longitudinal study of middle-aged men. Results showed that men with high aerobic fitness were up to 25% less likely to suffer a heart attack compared with those with the low aerobic fitness.
Maurice et al. (1953) studied London double decker bus drivers and their conductors. The more active conductors had significantly less incidence of C. H. D. than did the sedentary drivers. Can you think of any confounding factors in this study?
Brannon and Feist (1997) have found that regular physical exercise gives protection against stroke and improves the ratio of high density lipoproteins (H. D. L.) to low density lipoproteins (L. D. L.) (this translates as good and bad cholesterol levels respectively). This also reduces the risk of heart disease and protects against some forms of cancer. Regular physical exercise also prevents bone density loss and helps to control diabetes.
There are psychological benefits to exercising including decreased depression, reduced anxiety, providing a buffer against stress and increased self-esteem and well-being.
Exercise has been found to lower depressive moods in a variety of people, including young pregnant women from ethnically diverse backgrounds (Koniak-Griffin, 1994) and nursing home residents aged 66 to 97 (Ruuskanen and Parkatti, 1994). These findings could be due to the release of endogenous Opiates during exercise.
Exercise helps to reduce state anxiety (a temporary feeling of dread arising from a social situation). It is not clear whether exercise can influence trait anxiety (changing your personality so that you are less anxious). Both exercise and relaxation reduced anxiety. This may be because the change of pace reduces anxiety. Norvell and Belles (1993) showed how combining a non-aerobic weight training course with an opportunity to train away from the pressures of work resulted in significant increases in psychological health, including lowered anxiety levels. Both aerobic and non-aerobic exercise have been found to help people cope with anxiety, with even a single session having a positive effect on alleviating depression, fatigue and anger (Pierce and Pate, 1994).
Exercise is a buffer against stress. This could be because of the positive effect on the immune system. Exercise produces a rise in natural killer cell activity and an increase in the percentage of T-cells (lymphocytes) that bear natural killer cell markers (indicating the sites where killer cells are produced). This warns off invading cells before they have the chance to harm the body. Both exercise and stress reduce adrenaline and other hormones yet exercise has a beneficial effect on heart functioning whereas stress may produce lesions in heart tissue. In exercise adrenaline metabolises differently and is released infrequently and gradually under conditions for which it was intended (e.g. jogging). In conditions of stress adrenaline is discharged in a chronic and enhanced manner.
Sinyor et al. (1986) failed to find any significant stress buffering benefit for stress in healthy young men who began an aerobic exercise programme or a weight lifting intervention. Whereas Roth and Holmes (1985) found that college students who engaged in physical exercise reported fewer stress related health problems and depressive symptoms than did less active college students. However this effect was only found for students with high stress and low fitness, students with low stress to begin with did not have such poor health. So a combination of high stress and low fitness seems to produce poor health.
Sonstroem (1984) in a meta-analysis found a significant positive relationship between exercise and self esteem. Hogan (1989) has found a relationship between fitness and self-confidence and self discipline. Ross and Hayes (1988) have demonstrated a relationship between subjective physical health and psychological well-being.
Over exercising naturally can produce poor health or even death from at risk individuals who are not closely supervised (Brannon and Feist, 1997).
Nutrition: diet and health
Dietary habits
The MRFIT study (Stamler et al. 1986), was a longitudinal study over six years of three hundred and fifty thousand adults. A linear relationship was found between blood cholesterol level and the incidence of coronary heart disease (CHD) or stroke. The risk for individuals within the top third of cholesterol levels was three and a half times greater than those in the lowest third. A 24 year longitudinal study of American men working for western electricity found that men who consumed high levels of cholesterol were twice as likely to develop lung cancer compared with men who consumed low levels of cholesterol. Much of the cholesterol came from eggs (Shekelle et al, 1991).
Cholesterol combines with lipoproteins as it is metabolised to form a high-density lipoprotein (H. D. L.) and low-density lipoprotein (L. D. L.). H. D. L. is “good” cholesterol as it is involved in transportation from the arteries and other tissues to the liver. L. D. L. is “bad” cholesterol because it contributes to the formation of plaque within the arteries. About two-thirds of the British population are at risk of CHD owing to high cholesterol levels.
Blood cholesterol levels are to a significant degree mediated by dietary intake of fats. In America 44% of calories are consumed as fat. Be recommended level is 30%. Cholesterol levels are also affected by stress as stress causes cholesterol to not be metabolised by the liver. Other mediating factors are exercise levels and genetic factors.
Simone (1983) estimated that nutritional factors account for 60% of all cancer in women and 40% of all cancer in men in the USA.
Foods that are lacking in preservatives may result in high levels of bacteria and fungi being produced and spoiled food is a risk factor in stomach cancer. Food hygiene education and developments in food hygiene have produced a sharp decline in this disease.
Excessive use of salt has been linked to hypertension and to cardiovascular disease. High levels of fats and dietary cholesterol have been linked to atherosclerosis and coronary heart disease (CHD). A large scale study of Italian and American female breast cancer patients found that these patients do show increased fat intake in their diets; this was almost entirely due to their very high consumption of milk, high fat cheese and butter. Women who consumed half of their calories as fat had breast cancer rates that were three times higher than average. There was no difference between these cancer patients and healthy women in their consumption of carbohydrates and vegetable fats (Toniolo et al 1989). High intake of saturated fats is a risk factor for the severity of breast cancer in older women but not younger women (Verrault et al 1988). Both high and low levels of polyunsaturated facts were directly related to the severity of breast cancer of women.
Alcohol has been implicated in cancers of the tongue, oesophagus, liver and pancreas. In Norway frequent drinkers were five times more likely to suffer pancreatic cancer prepared with nondrinkers (Heuch et al, 1983). Drinking may also lead to cirrhosis of the liver.
Vitamins Aand C, and selenium, are thought to help reduce the risk of developing cancer. Deficiencies in vitamin A may lead to a deterioration in the stomachs protective lining. beta-carotene is a known protector against some types of cancer. Vitamin C also helps prevent the formation of nitrosamine carcinogens. Selenium is a trace element found in grain products and in meat from grain fed animals. In moderate amounts it may provide some protection against cancer.
High fibre diets protect men and women from cancer of the colon and the rectum. Fibre from fruits and vegetables offer more protection against colon cancer than that from cereals and other grains. Fruit consumption offers protection against lung cancer and we should be eating fruit 3 to 7 times per week (Fraser et al, 1991).
Obesity and eating disorders
Obesity is defined in terms of the percentage and distribution of an individual's body fat. Techniques used to assess the body fat range from using computer tomography (e.g. ultrasound waves) to magnetic resonance imaging (MRI). Obesity may also be defined in terms of body mass index (B. M. I.) which is calculated by dividing a person's weight by their height squared using metric units (i.e. kilogrammes and metres squared). Stunkarda (1984) suggested that obesity should be categorised as either mild (20 to 40% overweight), moderate (41 to 100% overweight) or severe (more than 100% overweight). This would suggest that 24% of American men and 27% of American women are at least mildly obese (Kuczmarski, 1992).
Obesity is associated with physical health problems such as cardiovascular disease, diabetes, joint trauma, cancer, hypertension and mortality. Obesity also is associated with psychological problems such as low self-esteem, and poor self image. Many people have false stereotypes and are misinformed about how others become obese. Such stereotypes probably were formulated in childhood (Lerner and Gellert, 1969).
There are three different types of theories that attempt to explain obesity; they are:
- Physiological theories suggesting that there are genetic elements.
- Metabolic rate theories proposing that obese people have a lower resting metabolic rate, burn up less calories when resting and therefore require less food. They also tend to have more fat cells which are genetically determined.
- Behavioural theories suggest that obese people tend to be less physically active and eat more food than required.
Eating disorders
The two main eating disorders are anorexia nervosa and bulimia.
Individuals are diagnosed as anorexic only if they weigh at least 15% less than their minimal normal weight and have stopped menstruating. In extreme cases, anorexics may weight less than 50% of their normal weight. Weight loss leads to a number of potentially dangerous side-effects, including emaciation (wasting of the body), susceptibility to infection and other symptoms of under nourishment. Females are 20 times more likely to develop anorexia than males. But horseracing Jockeys, who are usually male, are susceptible to anorexia. Anorexia particularly affects white, Western, middle to upper class, teenage women.
Another characteristic of anorexia nervosa is that of distortion of body
image. Anorexics think that they are too fat. This was investigated by
Garfinkel and Garner (1982). Participants used a device that could adjust
pictures of themselves and others up to 20 per cent above or below their actual
body size.
An anorexic was more likely to adjust the picture of herself
so that it was larger than the actual size. They did not do the same for
photographs of other people.
American undergraduates were shown figures of their own sex and asked to
indicate the figure that looked most like their own shape, their ideal figure
and the figure they found would be most attractive to the opposite sex.
Men selected
very similar figures for all three body shapes! Women chose ideal and
attractive body shapes that were much thinner than the shape that was indicated
as representing their current shape. Women tended to choose thinner body shapes
for all three choices (ideal, attractive and current) compared to the men
(Fallon and Rozin, 1985). The perfect figure has changed over the years. In the
1950s female sex symbols had much larger bodies compared with present-day
female sex symbols.
The hypothalamus is implicated in anorexia. The hypothalamus controls both eating and hormonal functions (which may also explain irregularities in menstruation).
Personality factors and family dynamics could also play a part in anorexia. The anorexic lacks self-confidence, needs approval, is conscientious, is a protectionist and feels the pressure to succeed (Taylor, 1995). Parental psychopathology or alcoholism also plays a part as does being in an extremely close or interdependent family with poor skills for communicating emotion or dealing with conflict (Rakoff, 1983). The mother daughter relationship has been implicated. Mothers of anorexic daughters tend to be dissatisfied with their daughter's appearance and tend to be vulnerable to eating disorders themselves (Pike and Rodin, 1991).
Birch (2000) found that American 5 to 9 year olds whose parents stopped them from eating foods they condemned as fattening were at much greater risk of suffering weight and eating problems.
They lost the ability to regulate their own food intake and, were unable to understand cues from their bodies telling them whether they were hungry or not, binged on the restricted food whenever their parents were not around to stop them.
According to the researchers, it was the mothers who were most concerned about their own weight and who dieted most often who were most likely to risk their daughters' health and self-image by attempting to restrict their diet.
'Essentially, mothers who used more restriction had daughters who, in the absence of hunger, ate more snack foods when they were available. This indicated a heightened response to the presence of palatable food and a consequent reduction in the ability to regulate energy intake in response to hunger and satiety cues.' Revealingly, girls were far more likely to demonstrate this effect than boys.
The phenomenon, according to the study, appears to be connected to affluence. While many middle-class mothers were obsessed with keeping themselves and their daughters thin, low-income parents were more concerned with feeding their children enough and so were far less likely to restrict their diet.
Half of the 200 five-year-olds interviewed gave worryingly informed responses to questions about dieting and weight loss. Asked why people dieted, some responded that it was to get thin so they could 'get more dates'.
Abridged from The Observer 3rd Sept 2000
In treating anorexia the patients weight is brought back up to a safe level in a residential setting using behavioural techniques based on operant condition. Success in the residential setting may not translate to the home environment and therefore family therapy may be necessary to help families learn more positive methods of communicating emotion and conflict.
Bulimia
Bulimia is characterised by recurrent episodes of binge eating followed by attempts to purge the excess eating by vomiting or using laxatives. The binges occur at least once a day usually in the evening and when alone. Vomiting and the use of laxatives disrupts the balance of the electrolyte potassium resulting in dehydration, cardiac arrhythmias and urinary infections.
This disorder mainly affects young women and is more common than anorexia affecting five to ten% of American women. Bulimia is not confined to middle or upper-class females and transcends racial, ethnic and socioeconomic boundaries. Like anorexia explanations encompass biological, personality and social factors. Bulimics often suffer from other disorders such as alcohol or drug abuse, impulsivity and kleptomania. It may be triggered by life events such as feeling guilty or feeling depressed. There is a stronger link between depression and bulimia compared with depression and anorexia. The depression seems to be linked to a deficit in the neurotransmitter substance serotonin. Bulimics may report lacking self-confidence and use food to fulfil their feelings of longing and emptiness. The binge eating and vomiting is justified in terms of needing to have a high calorie intake of food and a desire to stay slim.
Treatment involves medication and cognitive behavioural therapy. Antidepressants drugs are used in combination with psychotherapy. Treatment for bulimia tends to be more successful because bulimics recognise that they have a problem whereas anorexics don't.
Healthier than thou by Barbara Ellen, Observer, 10/09/00
|