Sabtu, 05 Mei 2012

Shisha Pipes: Is Smoking Them Really Harmless?

The sweet smelling tobacco is gaining in popularity, but most people who smoke it in cafes are unaware of the potential risks. 
You might call it shisha in Egypt and Sudan, nargile in Turkey and Syria or hookah in India. Some are made from clay, others from ornately carved metals or plastics. But the principle is same – these water-pipes allow you to smoke flavoured tobacco as it is bubbled through water. Maybe you know it simply as hubble-bubble. 
Sharing a water-pipe is thought to be harmless, relaxing fun. They are now enjoying something of a resurgence in popularity in India and the Middle East, where they are said to have originated. In the Middle East the trend has extended to teenagers and women, many of whom do not smoke cigarettes.
This shisha cafe culture has also extended to Europe, Brazil and the United States. If I run home from my office in London, I pass a street filled with cafes where groups of people sit outside engulfed in clouds of honey-scented smoke. In the United States many hookah cafes have opened in college towns and a recent study found that as many as a fifth of American students have tried it. In many countries these pipes are seen as safe enough to be exempt from legislation on smoking in public places.
But the idea that these pipes are harmless is a myth.

Smoke on the water
One of the main misconceptions is that the risks of tobacco are minimised because it is purified as it passes through the water. But this ignores the complete source of the smoke that enters your mouth.
The tobacco burns in a small dish on top of the main body of the water-pipe. You inhale through a mouthpiece connected by a pipe to a reservoir of water at the bottom. As you breathe in smoke is drawn from the burning tobacco and bubbles through the water and up into your mouth. The tobacco is sweetened with glycerine, which can make it damp, so charcoal is added to keep the tobacco burning.  This means the smoke inhaled derives from charcoal too, and charcoal contains several toxic substances, including carbon monoxide, heavy metals and tar.
Some water-pipes are sold with mouthpieces containing cotton filters or a plastic mesh. This does result in smaller bubbles, but a report by the World Health Organisation says there is no evidence that these mouthpieces reduce the harm.

Unknown risk
But surely the water cools the smoke, making it less dangerous than a cigarette?  It is true that this might make an individual puff less harmful, but this does not factor in the quantity of puffs. A typical water-pipe session lasts for at least 20 minutes, often for an hour. So instead of taking 8-12 puffs of a single cigarette a person is inhaling 50-200 puffs in a session. This, in effect, makes it more like chain smoking. In an hour-long session a person can inhale the equivalent of 100 to 200 times the smoke from a single cigarette, which may come as a surprise to most people. A survey carried out this year by the British Heart Foundation found that 84% of respondents thought the amount of smoke inhaled was equivalent to 10 cigarettes or fewer.  
In a study in Florida, USA, customers’ carbon monoxide levels were tested as they left bars that allowed the smoking either of cigarettes or hookah pipes. The people leaving the bars that had water-pipes had triple the levels of carbon monoxide in their bodies. Some reported feeling high, which the authors say could have been the early stages of carbon monoxide poisoning.
But what do we know about any long-term consequences? Here, the science is incomplete, as long-term studies of the kind conducted on cigarette tobacco have not been carried out. Researchers admit the evidence is scant, but suggest that smokers of water-pipes could be at long-term risk for nicotine dependence, cardiovascular disease and even cancer.  Professor Hani Najm, Head of Cardiac Surgery at National Guard Health Affairs in Saudi Arabia told me in an interview that he fears that water-pipe smoking could result in an escalation in heart disease in the Gulf States. So bear in mind one thing. Whether you call it shisha, nargile or hubble bubble, it might smell nice, but it is not as harmless as you might think.

Disclaimer
All content within this column is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or any other health care professional. The BBC is not responsible or liable for any diagnosis made by a user based on the content of this site. The BBC is not liable for the contents of any external internet sites listed, nor does it endorse any commercial product or service mentioned or advised on any of the sites. Always consult your own GP if you're in any way concerned about your health.

Does Cheese Give You Nightmares?

Our health expert Claudia Hammond sifts through the evidence behind the long-held claim
In A Christmas Carol, Ebenezer Scrooge blamed cheese for causing his ghostly night-time encounters.  He only ate “a crumb”, and the story may have had a happy ending, but the idea that cheese gives you nightmares still persists. Is there any truth to this?
A few years ago there were reports that different types of British cheese gave people different kinds of good and bad dreams, though none of the study volunteers reported having nightmares as such. Stilton-eaters had bizarre dreams, fans of Red Leicester dreamt about the past, and those who ate Lancashire before bed dreamt about the future. If you want to dream about celebrities, apparently you should make Cheddar your bedtime snack.
But bear in mind that this was a survey conducted by the body that promotes cheese in the UK, one that goes by the wonderful name of The British Cheese Board. There is no doubt that it was a clever piece of marketing, but as a scientific study it had fundamental flaws. There was no control group, so we do not know, for instance, whether people who did not eat cheese in the evenings had more or fewer bad dreams.

Perchance to dream
For argument’s sake, though, let’s explore whether there is anything in cheese that could promote bad dreams. Eating heavy meals with a high fat content late at night can give you indigestion, which in turn disturbs your sleep. Disturbed sleep often involves more nightmares, or at least the memory of more nightmares, because you wake more often and remember them.
In some countries the last course eaten in a big meal is cheese, which might suggest that cheese leads to nightmares, but it could of course be the quantity of food, rather than cheese in particular which led to indigestion. It is worth noting that as well as blaming the crumb of cheese for his apparitions, Scrooge also blames “an undigested bit of beef, “a blot of mustard”, or possibly “a fragment of an underdone potato”.
But there is another substance contained in cheese which might be pertinent here – tryptophan. It is an amino acid found in various foods, including milk, chicken, turkey and peanuts. The body uses it to produce serotonin, a chemical messenger associated with stable mood and sound sleep.  Sometimes it has been suggested that this is why people who celebrate Christmas or Thanksgiving with roast turkey often feel sleepy after lunch – that and the alcohol, of course. Studies on tryptophan as a sleeping pill have shown mixed results, but for some people it is effective.

Extreme response
The idea that cheese has strange effects on the mind could come from a very real, but rare phenomenon known as the “cheese reaction”. There is a class of older antidepressants called monoamine oxidase B inhibitors, which reduce the breakdown of chemicals such as serotonin. These drugs can be effective in treating depression, but they have an unusual and very serious side effect. They prevent the breakdown of the substance tyramine, which occurs naturally in cheese. If tyramine builds up it can cause blood pressure to rise to levels high enough to increase the risk of heart problems or stroke.
The cheese reaction can prove fatal, so although this antidepressant is used less commonly now, people taking it are given strict warnings to avoid cheese and other foods, including cured or pickled products.  The problem is that the amount of tyramine contained in foods is highly variable; when patients experiment they might find they are fine on one occasion, but have a serious reaction the next.
So, incomplete as the evidence is, there is no solid proof that eating cheese at night causes nightmares. What we can say with more certainty is that if you eat immediately before going to bed, or have over-eaten, then indigestion might give you a restless night. But it could be the case that a little cheese might even help you sleep more soundly.
  
Disclaimer
All content within this column is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or any other health care professional. The BBC is not responsible or liable for any diagnosis made by a user based on the content of this site. The BBC is not liable for the contents of any external internet sites listed, nor does it endorse any commercial product or service mentioned or advised on any of the sites. Always consult your own GP if you're in any way concerned about your health.

Why Do We Need to Sleep?

The question still perplexes scientists, but there are now several intriguing theories that explain our need for a daily nap.
Some people need eight hours. Others can exist on four. But the bottom line is that everybody needs sleep - it is as essential as breathing and eating. Yet, despite decades of study, scientists still do not know why we do it.
However, there are some intriguing clues and theories. One obvious clue is that we all feel better after a good night’s sleep, and much worse if deprived of a decent night’s rest. In humans the need for sleep gets so strong after a few days that nothing will keep you awake – with reports of people falling asleep standing up, even whilst being kicked or having intolerably loud music played at them. Within days of having no sleep, people report confusion, forgetfulness and hallucinations. (In case you are wondering, the world record for going without sleep is eleven days.)
But saying that we sleep because we are tired is rather like saying we eat because we are hungry – it is why we sleep, but not necessarily why we need it.

Memory aid
One theory that has emerged in recent years is that sleep helps us to process and consolidate new memories. Our memory system is a psychological wonder, and several studies have suggested that sleep provides some behind-the-scenes maintenance.
For instance, Matthew Walker and colleagues from the University of California gave volunteers aptitude tests like remembering sequences of patterns fired at them on a computer. Half the volunteers learned these patterns in the morning, and half in the evening. To test their memories he got them back into the lab – the morning learners returned after a full day of being awake, the evening learners came back after a night's sleep. Sure enough, those who were allowed to sleep had better recall of the test patterns­.
By the way, there is good news for siesta or powernap lovers. Similar comparisons indicate that you can get a memory boost from a daytime nap. So, if you have been studying or working hard in the morning, do not be too hard on yourself if you fancy closing your eyes for a while.
One school of thought is that sleep aids our memories by refreshing and reorganising them without interfering with our waking thoughts. Evidence comes from several studies using methods that record the brain directly. For instance, when rats were trained to find their way around a maze, their brains produced the same activity patterns during sleep as when they had carried out the task – suggesting that the brain was reconstructing the experience.
A rest might help ease bad experiences, too. A study published last year by Walker’s group has posed the intriguing suggestion that the brain might also deal with the memory of unpleasant or traumatic events during sleep (3).

Dream on
From this we also gain an important insight into the fascinating phenomenon of dreams. These crazy adventures our minds have while we are sleeping may be a product of our memories randomly activating so as to keep them fresh, and of the mind seeking connections between all the things we have recently experienced. This could also explain why hallucinations accompany sleep deprivation. Without the opportunity to reorganise our memories during sleep, dreams intrude into our waking lives, causing difficulty in distinguishing our inner lives from reality.
Much of this is informed speculation. It is likely that as well as fine-tuning our brains, our bodies use this opportunity to carry out a list of housekeeping tasks, for instance, repairing damaged cells.
But some scientists argue that the purpose of sleep may not be restorative. In fact, they argue that the very question "why do we sleep?" is mistaken, and that the real question should be "why are we awake?". If you are safe and warm and fed, it is a waste of energy to be awake and moving around (and possibly getting into trouble). Far better, this argument goes, is to be awake only when you have to and sleep when it suits you (4).
One thing is certain, not only do we have to sleep, but it is good for your mind and body as well. Although everyone needs a different amount of sleep, the average is about seven hours – and people who sleep a lot less than this are at a higher risk of various illnesses, such as heart disease, and a shortened lifespan.
So instead of feeling guilty the next time you fancy a nap, think about how much good it will do you.

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Are Cramps Caused by Lack of Salt?

This common affliction has often been ascribed to low salt levels in your diet, but what causes these painful aches is still a mystery.
You wake up in the middle of the night in agony. Your calf muscle seems to have a life of its own and is in spasm, causing an agonising pain down the back of your lower leg. You try to force your leg to relax without success, and you know you are in for a sleepless night. What you have is cramp, or charley horse as it is also known in North America. 
This type of cramp is very common, particularly in the late stages of pregnancy. It occurs more frequently as people get older or if they put on weight, but it can happen to anyone, either during the night or after exercise. The cause of this common affliction has often been ascribed to low salt levels in your diet, or more precisely the sodium that is in salt. Take some salt and ease the pain, so the story goes, but as I will explain there is a much simpler, salt-free solution.
Cramp occurs most often in the calf muscle at the back of the lower leg, the hamstrings at the back of the thigh or the quadriceps at the front. Occasionally it can indicate something more serious, such as claudication, a condition where insufficient oxygen reaches the muscles, causing them to tighten when a person walks. Or in rare cases, cramps can be caused by very low levels of calcium due to a problem with the parathyroid gland in the neck. But as Raymond Playford, Professor of Medicine at Barts and the London School of Medicine and Dentistry, says cramp is not associated with needing more salt in your diet in the majority of cases.

Shock treatment
What causes this cramp is something of a mystery. More than a century ago, people noticed that the men who stoked fires on ships were often afflicted, and it even became known as “stoker’s cramp”. This led to the theory that a lack of salt was the cause. The idea was that the heat of the fire caused the men to sweat so much that they became short of sodium. So naturally the assumption was that eating more salt would prevent the cramps.
A biological explanation for this is that the lack of salt and accompanying dehydration causes the spaces between the cells of the muscles to contract, which then increases pressure on the nerve terminals, leading to pain. The problem with this explanation is the lack of robust evidence for this. To be fair this is not an easy topic to study. Because cramps are involuntary you never quite know when they will happen, making them difficult to investigate. If you assembled people in a lab for observation you could wait a very long time before they got cramp.
This leaves observations of real-life environments, like the finding that American footballers suffer from cramp more when the weather is hot, lending further weight to the idea that, as with the stokers, this is all down to sweat loss and a lack of salt. The problem with this theory is that athletes in cold climates get cramp too. And when sodium loss was measured in athletes taking part in an ultra-marathon in Cape Town, South Africa, the difference between those who experienced cramp and those who did not was too small to be of clinical significance.
Another approach that has been tested is to induce cramps in brave volunteers using electric currents. If a lack of salt plays a part then it should require a smaller current to induce cramps in a person who is partially dehydrated and therefore low on salt. But Kevin Miller and colleagues at North Dakota State University in the US found that this made no difference – though they admit the effect of greater fluid losses on cramp threshold is not known.
If you think about the cramp remedy that you see on a sports field, it gives us a big clue that this does not have much to do with salt. When we feel that agonising pain, the best evidence suggests that it is stretching out the muscle, not fluids, that provides relief. If you feel that pain in your calf muscle you grasp your toes and gently ease your foot towards you. This stretches the muscle and eventually eases the pain. No increase in sodium levels, by whatever means, are needed.
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Disclaimer
All content within this column is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or any other health care professional. The BBC is not responsible or liable for any diagnosis made by a user based on the content of this site. The BBC is not liable for the contents of any external internet sites listed, nor does it endorse any commercial product or service mentioned or advised on any of the sites. Always consult your own GP if you're in any way concerned about your health.

A Trip Back to Your Roots

Thousands of people flock to Salt Lake City each year, not for Utah’s skiing or national parks, but to search through endless records of births, deaths and marriages at one the world's largest repositories of genealogy information on the planet.
There is a new breed of traveller focused on uncovering family narratives, as evidenced by the 1,500 visitors who visit the Family History Library every day. Run by the Mormon Church, it contains more than two billion names of the deceased, more than 2.2 million rolls of microfilm and 300,000 books.
Utah is not the only place focused on roots tourism. The newly opened £8.2 million Cumbria Archive Centre in England’s northwest, with records dating back to the 12th Century, is banking on the boom. The fact that Cumbria is home to relatives of three former US presidents: George Washington, Thomas Jefferson and Woodrow Wilson fuels interest among genealogy tourists there.
Genealogy tourism -- combining a trip away with a trip down memory lane -- is one of the fastest growing travel sectors, according to University of Illinois research.  One million people, for example, visit Scotland each year, motivated by their ancestral activities and generating £730 million for the economy, according to tourism authority VisitScotland.
Popular with baby boomers, this type of authentic, real life experience is a backlash against the bubble-like environment of all-inclusive resorts, theme parks, gaudy tourist attractions and cruises, according to the University of Illinois.
The global television phenomena, Who do you think you are? has also sparked renewed interest in genealogy. The show features famous people unearthing secrets from their past. And the digitisation of billions of human records and ubiquitous web access has made researching family trees a lot easier and more accessible.
Before you book a flight to your ancestral holiday destination, it is worth researching your roots on sites like Ancestry.com, FamilySearch.org or Genes Reunited. Your country’s national archives are also a good starting point. You can then arm yourself with names, death and marriage certificates, immigration and electoral rolls, as well as towns of origin. Before the latter half of the 20th Century people generally did not travel much, so it is easier to pinpoint names to places.
Also hone in on local museums, libraries, cemeteries and churches close to your family’s home town where you can do your research. You will be disappointed if you book a trip to the Scottish borders if your relatives were from the Outer Hebrides.
You will also find centralised research options in big cities, for instance Edinburgh, Dublin and London can be good places to begin your search if you are completely starting from scratch. The ScotlandsPeople Centre has records that go back 500 years, while the National Archives in Dublin offers advice to genealogy tourists, then there’s UK’s National Archives in London.
Tourism boards in Ireland, Scotland, England, Wales and Canada also actively promote, document and assist people on the hunt for their ancestors, with links and resources for the ancestrally curious on their websites.
If you reach a dead end, or do not have the time or inclination to keep looking yourself, there are companies like Ancestral Footsteps. For a hefty fee you get your own personal genealogist and a tailor-made luxury tour after months of research into your family tree. You can include a chauffeur-driven car and a filmed documentary of your experience as well. While Ancestral Attic in the US is even more specialised helping you arrange a family reunion with unknown relatives, specifically in Eastern Europe.
Various genealogical societies also organise trips to archive centres, where census, birth, marriage and death records are stored.
Finally, do not underestimate your hotel. Edinburgh’s Channings, for example, helps guests find a local genealogist. The Lodge at Doonbeg in Ireland’s County Clare has a genealogist in residence if you are looking for your Irish roots there. 
However, no amount of online searching, staring at microfilm or even a private luxury tour can match the actual discovery of, say, your great, great grandfather's headstone in the grounds of a tiny Devon chapel, or knocking on the door of that thatched village house that was home to your long-dead relatives. This is the thrill of genealogy tourism.
Genealogy trips require more planning than regular getaways. Plan at least six months in advance to track down ancestors and new relatives. And good luck.

How to Avoid Travel Scams

Watch your bags to avoid being targeted. (Press Association)

Taxi drivers, local tour companies and official-looking badges can't always be trusted by travelers.
Taxis are a common ruse for a scam. Never get into a cab unless you're sure it’s reputable, and always agree on a price beforehand.
Beware taxi drivers (or "helpful" strangers) who tell you that the hotel or attraction you want to go to is closed or fully booked. They are often paid commission by other hotels and restaurants to take you there instead.
Always double-check, through word of mouth, guidebooks or the internet, that local tour companies are reliable. Some will add unwanted extras to your trip (in exchange for commission), while others may take your money and vanish. Many ‘cheap’ buses taking non-locals across the Thai-Cambodian border, for example, fall into the first category.
Pressured buys are a favourite tactic. In Beijing, for instance, you may be invited to a traditional teahouse or art exhibition, and then presented with a huge bill or guilt-tripped into an expensive buy. Beware attractive strangers who invite you to bars only to vanish when a huge bill arrives.
An official-looking badge or uniform gives an extra layer of authority. If you are asked for cash or for your passport in an unusual situation, insist on checking with a police officer or senior-looking official first.
Lastly, refuse all unsolicited offers to buy goods that you are told you can sell at a profit back home. This is known as the gem scam. Despite all this, don't make paranoia your default setting when stepping off the plane. For one thing, scams are common enough at home – check out Directgov for some well-known examples.
This article was published in partnership with Lonely Planet Magazine.

Indonesia Profile

Spread across a chain of thousands of islands between Asia and Australia, Indonesia has the world's largest Muslim population.
Ethnically it is highly diverse, with more than 300 local languages. The people range from rural hunter-gatherers to a modern urban elite.
Indonesia has seen great turmoil in recent years, having faced the Asian financial crisis, the fall of President Suharto after 32 years in office, the first free elections since the 1960s, the loss of East Timor, independence demands from restive provinces, bloody ethnic and religious conflict and a devastating tsunami.
Sophisticated kingdoms existed before the arrival of the Dutch, who consolidated their hold over two centuries, eventually uniting the archipelago in around 1900.
After Japan's wartime occupation ended, independence was proclaimed in 1945 by Sukarno, the independence movement's leader. The Dutch transferred sovereignty in 1949 after an armed struggle. 

Papuanese tribal man 
There is great ethnic diversity across Indonesia's many islands
 
Long-term leader General Suharto came to power in the wake of an abortive coup in 1965. He imposed authoritarian rule while allowing technocrats to run the economy with considerable success.
But his policy of allowing army involvement in all levels of government, down to village level, fostered corruption. His "transmigration" programmes - which moved large numbers of landless farmers from Java to other parts of the country - fanned ethnic conflict.
Suharto fell from power after riots in 1998 and escaped efforts to bring him to justice for decades of dictatorship.
Post-Suharto Indonesia has made the transition to democracy. Power has been devolved away from the central government and the first direct presidential elections were held in 2004.
But the country faces demands for independence in several provinces, where secessionists have been encouraged by East Timor's 1999 success in breaking away after a traumatic 25 years of occupation. 

man sits on red carpet 
Indonesia has the world's largest Muslim population
 
 
Militant Islamic groups have flexed their muscles over the past few years. Some have been accused of having links with Osama Bin Laden's al-Qaeda organisation, including the group blamed for the 2002 Bali bombings, which killed 202 people.
Lying near the intersection of shifting tectonic plates, Indonesia is prone to earthquakes and volcanic eruptions. A powerful undersea quake in late 2004 sent massive waves crashing into coastal areas of Sumatra, and into coastal communities across south and east Asia. The disaster left more than 220,000 Indonesians dead or missing.

BBC Learning English - Exam Skills (Revision strategies)

 

Vocabulary

Activity 1

Circle the word that doesn’t fit in each group.

1. to encourage          to support          to criticise
2. slowly                    rapidly               gradually
3. minimum                utmost                least
4. inevitable               unpredictable      random
5. a summary             a synopsis          a complete text
6. absorption             expulsion            incorporation

Activity 2

Complete these sentences using the vocabulary items above. There may be more than one possible answer.

1. I wish my parents would __________________ me more. They don’t do anything to make me feel more confident.
2. I learnt those words quite __________________ - it only took about half an hour of revision.
3. We expect you to attend a __________________ of three classes a week.
4. It was __________________ that she would get the highest marks – she’s always been the best in the class.
5. Unfortunately you will need to read the __________________ as you need to know all the details.
6. Your __________________ of information depends on how well you can concentrate in class.