|
Protein and energy
supplementation in elderly people at risk from malnutrition.
Reference: Cochrane Database Syst Rev 2002;(3):CD003288
BACKGROUND: This review was carried out because evidence for the effectiveness
of
nutritional supplements containing protein and energy which are often prescribed
for elderly
people is limited. Furthermore malnutrition is more common in this age group and
deterioration of
nutritional status can occur during a stay in hospital. It is important to
establish whether
supplementing the diet with protein and energy is an effective way of improving
outcomes for
older people at risk from malnutrition. OBJECTIVES: This review examines the
evidence from
trials for improvement in nutritional status and clinical outcomes when extra
protein and energy
food were provided, usually in the form of commercial 'sip-feeds'. SEARCH
STRATEGY: We
searched The Cochrane Library (issue 1, 2001), MEDLINE (1966 to February 2001),
EMBASE (1980 to March 2001), Health star (1975 to March 2001), CINAHL (1982 to
Jan
2001), BIOSIS (1985 to March 2001) and CAB abstracts (1973 to March 2001). We
also
hand searched nutrition journals and reference lists and contacted 'sip-feed'
manufacturers. Date
of most recent search: March 2001. SELECTION CRITERIA: Randomised controlled
trials and
quasi-randomised controlled trials of oral protein and energy supplementation in
older people
with the exception of groups recovering from cancer treatment or in critical
care. DATA
COLLECTION AND ANALYSIS: Two reviewers independently assessed trials prior to
inclusion and independently extracted data and assessed trial quality; any
differences were
resolved by reaching consensus. Authors of trials were contacted for further
information as
necessary. MAIN RESULTS: Thirty-one trials with 2464 randomised participants
have been
included in the review. Most included trials had poor study quality. Mortality
data were
combined for meta-analysis from twenty-two trials (1755 participants). The
Relative Risk (RR)
indicated a lower mortality in the supplemented group compared with the control
group (0.67;
95% confidence interval (CI) 0.52 to 0.87). The risk of complications (total
complications if
available, otherwise for example the number of infections by the end of
follow-up) from nine trials
(608 participants) showed no significant difference (RR 0.93, 95% CI 0.77 to
1.13). We were
unable to combine trials for meta-analyses of functional outcome, for example
grip strength,
walking distance and Barthel Index, however there was little evidence of benefit
to functional
outcomes from individual studies. Data describing length of stay were available
from seven trials
(658 participants). There was some indication that mean length of stay was
shorter for the
supplemented groups (-3.4 days, 95% CI -6.12 to -0.69). REVIEWER'S CONCLUSIONS:
Supplementation appears to produce a small but consistent weight gain. There was
a statistically
significant beneficial effect on mortality and a shorter length of hospital
stay. Additional data from
large-scale multi-centre trials are still required to provide clear evidence of
benefit from protein
and energy supplements on mortality and length of hospital stay. Too few data
were reported and
the time scale of most studies was too short to have a realistic chance of
detecting differences in
morbidity, functional status and quality of life. Furthermore, most trials do
not address the
organisational and practical challenges faced by practitioners trying to meet
the individual needs
and preferences of those at risk from malnutrition.
Functional foods and the
immune system: a review.
Reference: Eur J Clin Nutr 2002 Aug;56 Suppl 3:S29-33
In the last decade, preventive medicine has undergone a great advance,
especially in developed
countries. Research has demonstrated that nutrition plays a crucial role in the
prevention of
chronic diseases, as most of them can be related to diet. Functional food enters
the concept of
considering food not only necessary for living but also as a source of mental
and physical
well-being, contributing to the prevention and reduction of risk factors for
several diseases or
enhancing certain physiological functions. In reference to the immune system,
many studies have
pointed out that not only pre- and probiotics, but also single micronutrients
incorporated into
functional foods contribute to an enhancement of immunocompetence. In fact, one
of the
authorized claims consists of pointing out the immunomodulator properties of
functional foods. In
this article, the effect of some functional foods and ingredients such as
probiotics, selenium and
dietary antioxidants (vitamins A, E and C) on the immune function are reviewed.
However, the
optimum intake level and recommended amounts of functional foods have not yet
been
established. Thus, in order to remove the controversy surrounding functional
food, further
research studies are necessary, both in experimental animals and in humans.
Finally: efforts should
be directed towards the ultimate goal, that is, a 'functional diet'.
Body
composition and hormonal responses to a carbohydrate-restricted diet.
Reference:
Metabolism 2002 Jul;51(7):864-70
The few studies that have examined body composition after a
carbohydrate-restricted diet have
reported enhanced fat loss and preservation of lean body mass in obese
individuals. The role of
hormones in mediating this response is unclear. We examined the effects of a
6-week
carbohydrate-restricted diet on total and regional body composition and the
relationships with
fasting hormone concentrations. Twelve healthy normal-weight men switched from
their habitual
diet (48% carbohydrate) to a carbohydrate-restricted diet (8% carbohydrate) for
6 weeks and 8
men served as controls, consuming their normal diet. Subjects were encouraged to
consume
adequate dietary energy to maintain body mass during the intervention. Total and
regional body
composition and fasting blood samples were assessed at weeks 0, 3, and 6 of the
experimental
period. Fat mass was significantly (P <or=.05) decreased (-3.4 kg) and lean body
mass
significantly increased (+1.1 kg) at week 6. There was a significant decrease in
serum insulin
(-34%), and an increase in total thyroxine (T(4)) (+11%) and the free T(4) index
(+13%).
Approximately 70% of the variability in fat loss on the carbohydrate-restricted
diet was
accounted for by the decrease in serum insulin concentrations. There were no
significant changes
in glucagon, total or free testosterone, sex hormone binding globulin (SHBG),
insulin-like growth
factor-I (IGF-I), cortisol, or triiodothyronine (T(3)) uptake, nor were there
significant changes in
body composition or hormones in the control group. Thus, we conclude that a
carbohydrate-restricted diet resulted in a significant reduction in fat mass and
a concomitant
increase in lean body mass in normal-weight men, which may be partially mediated
by the
reduction in circulating insulin concentrations.
Effects of dietary lipids on
serum lipid levels of hypertensive patients.
Reference: Zhonghua Yu Fang Yi Xue Za
Zhi 2002 Jul;36(4):250-3
OBJECTIVE: To survey the intake of dietary lipids and analyze serum lipid levels
in hypertensive
patients, and to study the effects of changing dietary lipids intake on the
serum lipid levels.
METHODS: To estimate the intake of dietary fat and to measure the level of serum
lipids in
hypertensive patients before and after intervention. RESULTS: The baseline
survey showed that
the intake of dietary fat and cholesterol were high in those patients. Their fat
intake is more than
30% of the total energy intake; serum total cholesterol (TC), triglycerides (TG)
and
LDL-cholesterol (LDL-C) levels were higher than the normal level. Correlation
analysis showed
that body mass index (BMI) and saturated fatty acid (SFA) intake were positively
correlated
with serum TC, TG and LDL-C; serum HDL-C/TC ratio was positively correlated with
monounsaturated fatty acid (MUFA) intake, and negatively correlated with BMI and
SFA. The
results implicated that MUFA is the protective factor against hypertension and
hyperlipidemia.
After one-year community-based nutrition intervention, the serum TC and LDL-C
levels of the
intervened subjects were reduced dramatically. CONCLUSION: The results indicate
that
reducing the intake of dietary fat and cholesterol and properly increasing
dietary MUFA intake
have significant effects on lowering serum lipids levels and controlling blood
pressure in
hypertensive patients.
|
Protein
and energy supplementation in elderly people at risk from malnutrition.