Sunday, April 05, 2009

How a cup of hot chocolate could boost brain power and stave off fatigue

The flavanol religion again. It is much more likely that other things in chocolate -- such as the stimulant theobromine -- were responsible for any effect. It is an enduring wonder that so many researchers think they "just know" what the causal path is. But with only 30 students tested, the generalizability of the results is highly questionable anyway

It is supposed to be the perfect bedtime drink to send you off to sleep. But in fact, a cup of hot chocolate could be just the thing to peep you up, scientists say. Research shows that flavanols - plant chemicals abundant in dark chocolate - stave off fatigue and boost mental sharpness. It is thought that they widen blood vessels, boosting blood flow to the brain.

Psychologists asked 30 people to carry out a battery of mental arithmetic tests before and after having a flavanol-rich chocolate drink or a dummy beverage. They found the sweet drink boosted performance on one of the tests, which involved repeatedly subtracting the number three from a start point of between 800 and 999.

The flavanols also appeared to counteract the tiredness brought on by doing the intensive arithmetic, the British Psychological Society's annual conference heard. Researcher Crystal Haskell (CORR) said: 'We asked them about their mental fatigue and that increased but the cocoa offset that increase.'

The study, carried out at the Brain, Performance and Nutrition Centre at Northumbria University, also found that a 500mg dose of flavanols was more effective than a higher one. With this being equivalent to five bars of chocolate a day, the researchers are now trying to find out if lower levels would also be of benefit.

Flavanols belong to a group of compounds called polyphenols, which are also abundant in red wine, tea, olive oil, onions, leeks, broccoli and blueberries.

Co-researcher David Kennedy said: 'The amounts we were giving them were more than you would get from eating small amounts in diet but there is quite a bit of evidence showing that general consumption over time is protective against neurodegenerative disease and decline in cognitive function. 'The more fruit and vegetables and things containing polyphenols that you eat, the better for your brain.'

Other research has credited flavanols with cutting the inflammation linked to heart disease, and with reducing the odds of dangerous blood clots. They are also said to help keep diabetes and high blood pressure under control.

One of the key attractions for many is that chocolate simply makes us feel good - stimulating the release of chemicals more normally associated with sex and exercise. Researchers have even gone as far as to claim that the smell of chocolate alone can protect against colds.

But, sadly for chocolate lovers, the treat's high fat and sugar content means dieticians recommend it is eaten as part of a balanced diet, rich in less appealing foods such a brown rice, pulses and fruit and vegetables.


Sports drinks 'can be worse for your teeth than cola'

I think the last paragraph below is the most persuasive. To ignore the role of saliva is quite amazing

They may enhance your performance on the pitch but energising sports drinks won't do the same for your winning smile, scientists say. Researchers found that some juices and squashes are so acidic that they can weaken the teeth after just a few mouthfuls. Taking regular sips during one day is enough to weaken the surface of a tooth, the scientists warned. The effects are even worse if you brush your teeth straight after taking a swig. Powerade, Gatorade, Vitamin Water, SoBe Life Water and Propel Fitness Water were all found to cause damage.

The research follows the rising popularity of sports drinks such as Lucozade. High in sugars and acids, they are designed to replace minerals and liquid lost during exercise - and to boost the athlete's energy. But past studies have shown that many are more corrosive than cola.

Their ingredients can be problematic - mainly the citric and ascorbic acid added to improve flavour and prevent the drink going off. Acid erodes the tooth's enamel coating and trickles into the bone-like material underneath, softening the tooth. If left untreated it can cause severe damage - and even tooth loss, the New York University researchers found.

Professor Mark Wolff, who led the study, said: 'This is the first time that the citric acid in sports drinks has been linked to erosive tooth wear.' His team looked at the effects of a sports drink on cows' teeth, which closely resemble human teeth. Half a tooth was dunked in a sports drink, the other half in water. 'Five teeth were immersed in each drink for 75 to 90 minutes to simulate the effects of sipping on sports drinks over the course of the day,' said Dr Wolff. When compared, the fragment exposed to sports drink had a 'significant amount' of erosion and softening, they told the annual meeting of the International Association for Dental Research, in Miami.

Brushing teeth immediately after having a drink can make the problem even worse, as the softened enamel is much more vulnerable to abrasive chemicals found in toothpaste.

In 2004, British dentists found that fizzy drinks double the chances of a 14-year-old suffering tooth erosion, which is more serious than tooth decay. Decay occurs when sugar reacts with bacteria in plaque to attack the areas between, or on top of, teeth. Erosion happens when the smooth, hard enamel is eaten away by acids, exposing dentine, the substance that makes up the bulk of a tooth, or even its root.

Lucozade Sport said: 'Sports drinks are functional drinks designed to keep people hydrated and refuelled during exercise. To avoid any dental issues we advise that it is not sipped or swilled around the mouth, but swallowed quickly.' A spokesman for Gatorade's Sports Science Institute said: 'This study does not replicate real life as the teeth were studied outside of the mouth. 'Ohio State University conducted a real-life study, the most comprehensive to date, and concluded that there is no relationship between the consumption of sports drinks and dental erosion.'


No comments: