Sunday, October 08, 2006
Exercise fails to cut obesity
When will people admit that a fat body is mostly the outcome of a genetic tendency towards overeating?
Giving young children more physical exercise does not stop them becoming obese, a study has shown. The Glasgow University study, based on work with more than 500 four-year-olds, counters the assumption that in an age dominated by television and computer games, children could slough off the pounds if they exercised more. The study, published in the British Medical Journal, set out to establish whether greater physical activity would prevent children from becoming overweight. They recruited 545 children in their last year at 36 nursery schools.
Half the schools instituted three extra half-hour sessions of physical play and activity every week, and parents were given information packs encouraging them to give their children more activity and less television. The other half had no extra activity or information. All the children were regularly weighed and measured and their body mass index (BMI - the relationship between weight and height used to check for obesity) was calculated. There was no difference between the groups. "We found no significant effect of the intervention on physical activity, sedentary behaviour or body mass index," wrote the researchers. Nor did the children show less tendency to sit about or more inclination to run around. The only positive finding was that the more active children had better motor and movement skills, which may make them more confident about doing physical activity in the future.
The authors say the study is one of the few into the prevention of obesity in children. Yet the problem is serious: in Scotland in 2001 at least 10 per cent of children aged four to five and 20 per cent aged 11 to 12 were obese. The researchers wrote: "Successful interventions to prevent obesity in early childhood may require changes not just at nursery, school and home but in the wider environment. Changes in other behaviours, including diet, may also be necessary."
The British Heart Foundation, which part-funded the study, accepted the research was solid, but said it did not mean it was not necessary to encourage children to run around and play. "It's absolutely vital for young children to be active," said prevention and care director Mike Knapton. "Although this study suggests that the benefits of a small amount of extra exercise for nursery children are not visible immediately, we know it's crucial to encourage good exercise habits from an early age. Children get less active as they get older so it's vital that youngsters get regular physical activity to lay the foundations for good health as they grow up."
Source
Black tea 'soothes away stress'
Scientists have proved what many tea drinkers already know - a regular cuppa can help you recover more quickly from the stresses of everyday life. A team at University College London found black tea helps to cut levels of the stress hormone cortisol circulating in the blood. They found people who drank tea were able to de-stress more quickly than those who drank a fake tea substitute. The study appears in the journal Psychopharmacology.
In the study, 75 young male regular tea drinkers were split into two groups and monitored for six weeks. They all gave up their normal tea, coffee and caffeinated beverages, and then one group was given a fruit-flavoured caffeinated tea mixture made up of the constituents of an average cup of black tea. The other group was given a caffeinated placebo identical in taste, but devoid of the active tea ingredients.
All drinks were tea-coloured, but were designed to mask some of the normal sensory cues associated with tea drinking (such as smell, taste and familiarity of the brew). This was designed to eliminate confounding factors such as the 'comforting' effect of drinking a cup of tea. Both groups were subjected to challenging tasks, while their cortisol, blood pressure, blood platelet and self-rated levels of stress were measured.
In one task, volunteers were exposed to one of three stressful situations (threat of unemployment, a shop-lifting accusation or an incident in a nursing home), where they had to prepare a verbal response and argue their case in front of a camera. The tasks triggered substantial increases in blood pressure, heart rate and subjective stress ratings in both of the groups. However, 50 minutes after the task, cortisol levels had dropped by an average of 47% in the tea-drinking group compared with 27% in the fake tea group. Blood platelet activation - linked to blood clotting and the risk of heart attacks - was also lower in the tea drinkers. In addition, this group reported a greater degree of relaxation in the recovery period after the task.
Researcher Professor Andrew Steptoe said: "Drinking tea has traditionally been associated with stress relief, and many people believe that drinking tea helps them relax after facing the stresses of everyday life. "However, scientific evidence for the relaxing properties of tea is quite limited." Professor Steptoe said it was unclear what ingredients in tea were responsible. He said it was very complex, and ingredients such as catechins, polyphenols, flavonoids and amino acids had all been found to affect neurotransmitters in the brain. Nevertheless, the study suggests that drinking black tea may speed up our recovery from the daily stresses in life. "Although it does not appear to reduce the actual levels of stress we experience, tea does seem to have a greater effect in bringing stress hormone levels back to normal. "This has important health implications because slow recovery following acute stress has been associated with a greater risk of chronic illnesses such as coronary heart disease."
Source
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Just some problems with the "Obesity" war:
1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).
2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.
3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.
4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.
5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?
6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.
7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.
8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? [/sarcasm].
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