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Good Nutrition is Ageless
The fastest growing segment of the population in most
industrialized countries is the elderly. And too often this is
also a group most susceptible to many health risks from a nutrient
poor diet. Evidence from numerous sources indicate that a
significant number of elderly fail to get the amounts and types of
food necessary to meet essential energy and nutrient needs. There
are a wide range of reasons why older individuals might not be
eating the most nutritious diet which is all the more reason why
health professionals and care providers need to be constantly aware
of the necessity for maintaining an optimal nutritional health
status in the elderly. Physiological, psychological and economical
changes in the later years can all contribute to poor nutrition
among the elderly, and accordingly establishment of healthy
nutritional habits often requires a multifaceted intervention
approach to address the wide range of factors contributing to
suboptimal nutrient intakes.
After age fifty there are many metabolic and physiological changes
which impact on the nutritional needs of an individual. The
metabolic rate slows and can decline as much as thirty percent over
a lifetime. This results in decreased caloric needs which can be
complicated by changes in an older person's ability to balance food
intake and energy needs. Even with a decreased caloric need, many
older people have difficulty getting sufficient calories which can
eventually lead to chronic fatigue, depression, and a weakened
immune system.
As we age our body composition changes with a decrease in lean
tissue mass (as much as 25%) and an increase in body fat. Such
changes can be accelerated because older adults utilize dietary
protein less efficiently and may actually need a greater than
recommended amount of high quality protein in their diet to maintain
lean tissue mass. These changes in metabolism and physiology can be
exaggerated due to complications from digestive difficulties, oral
and dental problems, and medication-related eating and nutrient
problems.
And while there are many physical and clinical factors that can
contribute to under-nutrition in the elderly, there are as many
equally important social and economic factors which can further
complicate the nutritional well-being of an older individual.
Contributing factors include loneliness, lack of cooking skills,
depression, economic concerns, weakness and fatigue, and, in too
many cases, an unwarranted fear of many high quality, nutrient
dense, affordable foods. All these factors can contribute to the
fact that a significant number of older men and women consume less
food than required to meet energy and nutrient requirements, and are
at moderate to high nutritional risk.
The nutritional risk of the elderly is no doubt affected by the fact
that the low-fat, low-cholesterol diet message has been heard loud
and clear by this population. Many elderly readily accept the fear
of fat and cholesterol message because of their heightened concern
regarding their own health, and the knowledge that the risk for
chronic diseases increases with age. And while dietary limits on fat
and cholesterol consumption are widely assumed to be effective
risk-reduction interventions in young and middle-aged adults, the
appropriateness of such dietary restrictions in older individuals
has become an area of considerable debate.
There is evidence that good nutrition promotes vitality and
independence whereas poor nutrition can prolong recovery from
illness, increase the costs and incidence of institutionalization,
and lead to a poorer quality of life. Good nutrition is ageless and
the message to older people must be that the quality of your
nutrition is basic to the quality of your life. And while the
evidence of the value of nutritional balance is clear, the
nutritional status of many older individuals lacks that balance and
the problem is often complicated by a fear of foods and
over-emphasis on single nutrient issues. In this review we will look
at the relative benefits of cardiovascular risk reduction with
dietary restrictions versus the potential risks to the nutritional
well-being of the elderly when these interventions often result in
reductions in many nutrient dense
foods.
The real question which must be addressed is whether the "one diet
fits all" approach readily fits both the nutritional needs and
health concerns of the elderly. Dietary restrictions of fat
and cholesterol are implemented in order to lower plasma cholesterol
levels and the associated cardiovascular disease risk. The bases for
this dietary intervention approach to risk reduction are studies in
middle aged populations which indicated that an elevated plasma
cholesterol level is an independent risk factor for heart disease
and that reduction of an elevated cholesterol reduced relative risk.
To date, however, there have been no long-term drug or dietary
plasma cholesterol lowering intervention trials in healthy patients
older than 65 years. Some investigators have presented data
indicating that while total cholesterol levels are an excellent
predictor of CHD risk in middle-age, they are a poor indicator of
events in elderly patients [Corti et al. 1995]. Krumholz et al.
(1994) followed 997 subjects 65 years and older for 4 years and was
unable to document a graded and continuous association between
plasma cholesterol levels and CHD mortality or all-cause mortality
in persons older than 70 years. Studies by Kronmal et al. (1993),
using data from the Framingham Heart Study, indicated that HDL
cholesterol levels are a better predictor of risk in the elderly
than LDL cholesterol. Analysis of the data to determine the
relationship between the various causes of mortality in the
different age groups and specific plasma lipoprotein cholesterol
levels indicated that for CHD mortality the positive association
with LDL cholesterol decreased with age. HDL cholesterol was a
strong negative predictor of CHD mortality until past 80 years of
age. For total mortality the relationship with LD from positive to
negative at 62 years of age. In contrast, HDL cholesterol levels
were positively associated with better survival at all ages. Similar
results have been reported by Corti et al. (1995) showing that the
relative risk of death from CHD in persons 71 years and older is 2.5
times higher with an HDL less than 35 mg/dl compared to those with
levels greater than 60 mg/dl. The authors estimated that for each
unit increase in the total:HDL cholesterol ratio there was a 17%
increase in the risk of CHD death.
One of the unfortunate consequences of the lower-fat diet message is
that often the replacement for fat calories are calories from simple
carbohydrates which can elevate plasma triglyceride levels resulting
in lower HDL cholesterol concentrations which has been shown to be
an important determinant of CHD risk in the elderly. An additional
effect of a low-fat, high simple carbohydrate diet is to increase
the expression of small, dense LDL particles (Krauss and Dreon 1995)
which are relatively more atherogenic than larger, more buoyant
particles (Gardner et al. 1996).
There are also concerns that low-fat diets may in some individuals
exacerbate insulin resistance leading to hyperinsulinemia which is
an independent risk factor for CHD (Despres et al. 1996). It should
also be noted that calorie dense foods too often are the easiest
replacement for the higher fat, nutrient dense foods. With a
diminished sense of caloric balance the intake of high carbohydrate
foods can readily lead to obesity and its associated risk of CHD (Rimm
et al. 1995). Intake of calorie dense, nutrient poor foods can also
lead to decreased intakes of many important nutrients thought to
play important roles in decreasing CHD risk. These include the fat
and water soluble antioxidants to minimize production of oxidized
LDL (Hodis et al. 1995, Kushi et al. 1996), vitamins B12 and folate
to reduce the risks associated with elevated levels of plasma
homocysteine (Boushey et al. 1995, Herzlich et al. 1996), and other
vitamins and minerals thought to play roles in the regulation of
plasma lipoproteins and blood pressure.
In too many cases it is simply easy for the elderly individual to
reduce consumption of the many valuable nutrients found in abundance
in the food groups they have been advised to restrict or in some
cases actually eliminate. Re-patterning dietary choices in an
elderly individual can result in elimination of major food groups
from the diet without any real nutritional benefit, and with some
nutritional risk. It is for reason such as this that it is essential
that the impact of dietary modifications for fat intake on the
overall quality of the diets of elders be carefully evaluated. It
has been recommended that dietary modifications for older adults not
be overly restrictive and that the major emphasis should be on
dietary needs to address immediate problems such as diabetes, food
allergies and renal problems.
Nutrition advise for older adults should be designed to respond to
the changing physiological, psychological, social and economic
capabilities of the individual while assuring that the overall
nutritional needs are meet with the freedom to keep meals and eating
an important aspect to the quality of life during the later years.
http://www.enc-online.org/elderly.htm
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