Maintaining good
hydration with a variety of beverages.
A recently published
study which monitored hydration parameters of two groups of healthy,
sedentary individuals found that including or excluding plain water
as part of daily fluid intake had no impact on hydration
status
Twenty-seven males,
during two three-day periods in a 24 hour controlled environment,
consumed one of two diets in a randomised, crossover trial. One
group drank water and other beverages; and another group drank a
variety of beverages, but no water. The levels of physical activity
and the environments were the same for all who participated in the
study. Body weight and 24-hour urine volumes and twenty-four hour
creatinine levels were measured. Pre-and post-trial urine samples
and 24-hour urines were assayed for osmolality, specific gravity,
chloride, sodium and potassium, and sodium/potassium ratios were
calculated. Using these parameters, no differences were found
between hydration status of the two groups.
“All people need to
think about drinking enough fluids to stay hydrated, especially
during the hot summer months.” says Kristin Reimers, a member of the
research group “Choosing the beverages you enjoy can have a positive
impact on your hydration status.”
Grandjean A.C. et al, (2003)
Journal of the American College of Nutrition, Vol. 22, No. 2,
165-173
TV watching is linked
with risk of obesity and Type 2 diabetes
A large prospective
cohort study of American middle-aged women has found a direct
positive association between time spent watching TV and onset of
Type 2 diabetes, and obesity.
The study followed women
who were free of diagnosed diabetes, coronary heart disease, cancer
and in the case of those tracked for obesity, had a BMI of less than
30. After 6 years the researchers found that for every 2 hours/day
increment in TV watching the risk of becoming obese increased by
23%, and risk for onset of Type 2 diabetes increased by 14%.
Conversely, 1 hour/day of brisk walking reduced the risk of becoming
obese by 24% and the risk of developing Type 2 diabetes was reduced
by 34%. Other forms of sedentary behaviour such as prolonged periods
of sitting or standing at work and in the home were also
significant, although less strong, predictors for the onset of
diabetes and obesity.
The researchers point
out that this analysis of sedentary behaviour and its clinical
associations is one of the first large scale studies that has
analysed the association between specific sedentary activities and
the onset of chronic degenerative disease. The authors cite a 1997
study which found that American women on average watch 34 hours of
television per week, and other studies which have found that
metabolic rate whilst watching TV is lower than metabolic rate
during other forms of sedentary activities such as reading, and
sewing.
The authors suggest that
limiting TV viewing time to 10 hours per week, and establishing a 30
minutes of brisk walking per day habit, could reduce risk of
developing Type 2 diabetes by 43% and the risk of obesity by
30%.
The study by Hu et al,
was published in the Journal of the American Medical Association 9/4
2003, Vol 289: No. 14, pp1785-1791.
Heart-healthy diets
research results
A recent study published
in the Lancet found that heart disease risk amongst Asian
populations was significantly reduced by augmenting the traditional
Indian diet, with a diet designed to boost linolenic acid intake,
with nuts, fruits and vegetables, wholegrains, and vegetable oils
rich in alpla-linolenic acid, such as canola and mustard oils. The
study involved a randomised trial among 1000 patients with a history
of risk factors associated with coronary vascular disease, such as
angina, and Type 2 diabetes.
After two years, those
following the intervention diet were found to be consuming twice as
much linolenic acid as the control group, who were consuming a more
typical Asian diet. The intervention group experienced significantly
less cardiac events, including fatal and non-fatal heart attacks and
episodes of angina.
Another study
published in April 2003 European Journal of Clinical Nutrition, of
11,000 Italian residents, who had had a heart attack, and were
advised to more closely follow Mediterranean-style diet, with
increased consumption of fish, fruits, olive oil, plus raw and
cooked vegetables, also found significant health benefits. After 6.5
years, there was a linear decrease in mortality from any cause
amongst the intervention group.
The economic
consequences of micronutrient deficiencies
A recent study,
commissioned by the Micronutrient Initiative of the economic cost of
iron deficiencies in ten developing countries, estimated that on
average these countries lost 0.6% of gross domestic product (GDP),
as a result of iron deficiency amongst the adult working population.
A further 3.5% of GDP is lost as a result of iron-deficiency anaemia
amongst children, whose learning and physical performance potential
is seriously impaired by iron deficiency.
According to Sue Horton,
a University of Toronto economics professor and lead author of the
study, ‘The Economics of Iron Deficiency’. “One in three of the
world’s population suffers from anaemia so this has tremendous
economic consequences...........A loss of 4 per cent of GDP even in
poor countries translates into billions of dollars lost.”
The authors recommend
iron fortification as an extremely important and inexpensive dietary
intervention. The World Bank is cited, estimating that the economic
and social payoffs of micronutrient intervention are up to 84 times
programme costs.
The study was published
in Food Policy, February 2003, Vol. 28, No. 1, pp. 51-75.
