Some people swear by hair of the dog as a hangover cure, some sing the praises
of aspirin and bananas or Vegemite and water, while others say that nothing
is better than a good old-fashioned fried breakfast. None of these supposed
hangover remedies, however, is anything of the sort, according to a study by
two American doctors which suggests that the idea you can cure a hangover is
a medical myth.
The delusion that it is possible to prevent or alleviate the after-effects of
a night's over-indulgence is one of six pieces of folk wisdom often trotted
out at Christmas that have been punctured by Rachel Vreeman and Aaron
Carroll, of the Indiana University School of Medicine.
Other popular beliefs they say have no foundation in fact include the idea
that sugar makes children hyperactive, that midnight feasts make you fat,
and that you should always wear a hat in cold weather because almost half
our body heat escapes through the head.
In a paper published in the Christmas issue of the British Medical Journal,
the doctors have trawled the published scientific literature for the
evidence behind these common claims. Here are their conclusions.
Hangover cures
Dozens if not hundreds of remedies have been proposed over the years, many of
which are said to have a medical foundation. Many are even advocated by
doctors.
Dr Vreeman and Dr Carroll could find no evidence from randomised trials — the
gold standard for medical research — suggesting that any of them worked.
Good studies were available evaluating the herb borage, the artichoke,
prickly pear, Vegemite, fructose, glucose, tolfenamic acid and propranolol.
None had any effect.
“From aspirin and bananas to Vegemite and water, internet searches present
seemingly endless options for preventing or treating alcohol hangovers,” the
doctors said. “No scientific evidence, however, supports any cure or
effective prevention.”
Why you might think otherwise:
A few small studies have suggested that fluid and salt replacement might be
helpful. Hangovers also get better with time — thus whatever you have taken
will eventually seem to work.
Sugar and hyperactivity
Many parents believe that sugar makes their children more restless and
hyperactive, and deliberately limit their intake of sweets and fizzy drinks
accordingly. Yet this supposed link has been extensively researched and does
not hold up well. Dr Vreeman and Dr Carroll found 12 double-blind,
randomised controlled trials investigating the issue, and not one found
differences in hyperactivity between those who consumed large amounts of
sugar and those who did not.
Studies have found that when parents think that their children have been given
a sugary drink, even when it is sugar-free, they rate their children's
behaviour as more hyperactive. “The differences were in the parents' minds”,
the researchers said.
Why you might think otherwise:
There is good evidence that has linked some other ingredients of sweets and
soft drinks, such as artificial food colours, to hyperactivity. Many parents
thus make the association with sugar, though it is not to blame.
Hats and heat loss
It is a maxim of winter health advice that every parent knows: children should
always wear a hat in cold weather, because human beings lose almost half
their body heat through their heads. Even the US Army agrees: its field
manual recommends hats because “40 to 45 per cent of body heat” escapes
through the head.
Research published in the Journal of Applied Physiology, however, has
shown that there is nothing special about heat loss and the human head. The
body loses heat according to surface area, and while an exposed head can
certainly radiate a lot of heat, so can an exposed arm or leg. If people
wear swimsuits, only about 10per cent of heat is lost through the head.
Dr Vreeman and Dr Carroll pointed out that basic commonsense showed flaws in
the head and heat loss thesis — if true, it would mean that a person going
outside without wearing trousers would be no more cold than a person who
forgot to wear a hat.
Why you might think otherwise:
The myth probably began with military experiments conducted in the 1950s that
measured heat loss among soldiers wearing survival suits in the Arctic.
However, they wore no hats — so it is hardly surprising they lost more heat
through their heads.
Suicides and Christmas
“The combined stresses of family dysfunction, exacerbations in loneliness and
more depression over the cold dark winter months are commonly thought to
increase the number of suicides,” Dr Vreeman and Dr Carroll said.
While a long-running Japanese study found that suicide rates were higher after
the Christmas season and lower before, a US study over 35 years found no
such trend.
A study in Ireland that ran from 1990 to 1998 found no increase over
Christmas, and Irish men were found to be less likely to kill themselves
than at other times of year.
Other research, from Finland and Hungary, has found that suicides were more
common in summer than in winter. “None of this evidence suggests that
suicides do not happen over the holidays. The epidemiological evidence just
does not support that the holidays are a time of increased risk,” the
doctors say.
Why you might think otherwise:
Suicides at Christmas make news stories at a time when there is often little
else, and thus tend to make the headlines more than at other times of the
year.
There is also evidence that divorce proceedings are started more often
immediately after Christmas.
Eating late and obesity
People who want to lose weight are often advised to avoid eating too soon
before they go to bed. Folk wisdom has it that you won't burn the calories
as effectively because you will be resting .
The evidence, however, is quite clear. When you eat makes no difference: what
counts is what you eat, how much of it, and how much exercise you do
throughout the day. Several randomised studies have shown that there is no
connection between eating late and weight gain, so long as calorie intake
and exercise are otherwise the same.
“People gain weight because they take in more calories overall than they burn
up,” the researchers said. “Taking in more calories makes you gain weight,
regardless of when calories are consumed.”
Why you might think otherwise:
Obese people often tend to eat late at night — but this is because they eat
more meals and snacks in general. There is also evidence that people who
sleep badly, for example because of shift work, have a higher risk of weight
gain, and these people may tend to eat late.
Poisonous poinsettias
The red and white flowers and green leaves of poinsettia plants make them a
popular Christmas decoration. Some families with children, however, will not
buy them or will always place them on high shelves, because of a widespread
belief that they are poisonous.
An analysis of cases of poinsettia ingestion reported to the American
Association of Poison Control Centres, however, has found no evidence that
the plants are toxic.
Of 22,793 cases, none resulted in death and 96 per cent did not require
medical treatment.
A study of rats could not find a toxic amount of poinsettia, even when the
animals consumed quantities equivalent to 500 to 600 leaves.
Why you might think otherwise:
It is hard to find an obvious root for this myth. Some garden websites do
promote it, however.
