Tuesday, June 19, 2012

Seven cups of tea a day 'raises incidence of prostate cancer by 50%' among Glaswegians

Some reasonable reservations expressed below about these unusual results.  I will refrain from making jokes about Glasgow

Men who drink lots of tea are far more likely to develop prostate cancer, researchers have warned.  They found that those who drank seven or more cups a day had a 50 per cent higher risk of contracting the disease than men who had three or fewer.

The warning comes after scientists at the University of Glasgow tracked the health of more than 6,000 men for four decades.

Their findings run counter to previous research, which had suggested that tea-drinking lowers the risk of cancer, as well as heart disease, diabetes and Parkinson’s disease.

The study, led by Dr Kashif Shafique, began in 1970.  Participants aged between 21 and 75 were asked to complete a questionnaire about their usual consumption of tea, coffee and alcohol as well as their smoking habits and general health, and had to attend a screening examination.

Just under a quarter of the 6,016 men were heavy tea drinkers, consuming seven or more cups a day. Of these, 6.4 per cent developed prostate cancer over the next  37 years.

Researchers found that the subjects who drank the most tea were often teetotal and led healthy lifestyles.

As a result, they may have been at a lower risk of death from ‘competing causes’, effectively giving them more time to develop prostate cancer, the journal Nutrition and Cancer reports.

Dr Shafique said: ‘Most previous research has shown either no relationship with prostate cancer for black tea, or some preventive effect of green tea.  'We don’t know whether tea itself is a risk factor or if tea-drinkers are generally healthier and live to an older age, when prostate cancer is more common anyway.'

He added that those drinking the most tea were less likely to be overweight or drink alcohol, and more likely to have healthy cholesterol levels.

‘However, we did adjust for these differences in our analysis and still found that men who drank the most tea were at greater risk of prostate cancer,’ he said.  Dr Shafique did stress, however, that his team was ‘unaware of any constituent of black tea that may be responsible for carcinogenic activity in prostate cells’.

Previous research has found health benefits from flavonoids – antioxidant compounds in tea that are thought to control inflammation, reduce excess blood clotting and limit narrowing of the arteries.

Of seven previous studies on black tea and prostate cancer, four found a potentially protective effect while the remainder found no effect either way.

Dr Kate Holmes, head of research at The Prostate Cancer Charity, said: ‘Whilst it does appear that those who drank seven or more cups of tea each day had an increased risk of developing prostate cancer, this did not take into consideration family history or any other dietary elements other than tea, coffee and alcohol intake.

‘It is therefore unclear as to whether there were other factors in play which may have had a greater impact on risk.’

Almost 80 per cent of Britons drink tea, consuming an estimated 165million cups each day. The British tea industry is thought to be worth more than £700million a year.

Dr Carrie Ruxton of the Tea Advisory Panel, an educational body funded by the industry, said just 92 men in the Glasgow study drank more than seven cups a day and went on to develop prostate cancer.

She added: ‘We’re lacking the complete picture because we don’t know what other dietary factors were involved. Other research suggests tea has a protective or neutral effect on prostate cancer, and the authors acknowledge there is no known ingredient in tea that is cancer-causing.

‘Tea-drinking may be a marker for some sort of behaviour that can raise the risk of prostate cancer, but the study does not show it is a cause.’

Prostate cancer strikes 40,000 British men each year, causing more than 10,000 deaths


More publicity for the serious side effects of Statins

Which were once almost universally pooh-poohed as minor

Women on statins, the anti-cholesterol drugs, are at risk of fatigue, a U.S. study has found.  Two in five women taking the pills had less energy than before, with one in ten reporting they felt ‘much worse’.

While experts stress that patients should never stop taking their pills before speaking with their doctor, it has been suggested that for some women, this side-effect could outweigh the benefits of the drug.

This news comes on top of previous research that suggested women may not benefit from statins as much as men.

So should women carry on taking the pills? We asked the experts...


Statins reduce the amount of LDL (‘bad’) cholesterol, which can lead to hardening and narrowing of the arteries, raising the risk of heart disease, heart attack and stroke.

Statins are recommended for those with heart disease or a high risk of developing it.

Around five million Britons are taking statins, though last month, a review by researchers at the University of Oxford said everyone over 50 could benefit from them.


The new study into fatigue involved two leading statins, pravastatin and simvastatin.

The researchers at UC San Diego School of Medicine looked at more than 1,000 adults, a third of them women, and the effects of statins on energy levels and exercise capacity.

Participants were randomly given a placebo or a statin at an average dose — pravastatin (40mg) or simvastatin (20mg).

The effect appeared to be stronger for simvastatin.
Statins are recommended for those with heart disease or a high risk of developing it

Statins are recommended for those with heart disease or a high risk of developing it


Most people think cholesterol comes from our diets — in fact, most is made in the liver.  Statins work by blocking enzymes involved in the production of cholesterol.

However, many hormones, including oestrogen, are also metabolised by the liver and it’s thought statins may interfere with this, says Dr Sovra Whitcroft, a gynaecologist at the Surrey Park Clinic in Guildford.

‘As oestrogen promotes sleep, any disruption to its levels could lead to tiredness.’


The list of officially acknowledged side-effects has grown. Initially these included upset stomach, headache or insomnia. Memory problems were added in 2009.

However, GPs point to other side-effects such as irritability and ‘generally feeling old’ that are never mentioned in studies, yet are common.

Another concern is hair loss.  Dr David Fenton, a consultant dermatologist in London, says this is a rare side-effect he has witnessed.

‘Women shed more hair than they should, and it can exacerbate any genetic tendency towards the female equivalent of male pattern baldness. I see many with thinning patches.’

A recent Greek study, published in the International Journal of Cardiology, suggested up to 10 per cent of patients reported myopathy — muscle pain.

‘There has not been a post-marketing surveillance study of statins,’ says Dr Malcolm Kendrick, a Cheshire GP and author of The Great Cholesterol Con.  ‘So no one really knows what the adverse effects may be or how many people experience them.

‘Some say side-effects are vanishingly rare. But many patients I see have probable side-effects from a statin with a significant impact on their quality of life.’

And many experts agree women seem to suffer more side-effects than men.  Dr Richard Karas of Tufts University Medical Center in Boston, U.S., says because women are smaller and tend to be older when prescribed statins, this might contribute.

However, the British Heart Foundation reports only one in every 10,000 people who take statins will experience a potentially dangerous side-effect.

The NHS estimates statins save 7,000 lives a year, so the risks are seen to be outweighed by the benefits.


It's generally accepted that for people who have had a heart attack, stroke, or have heart disease, statins can be a life-saver.

But more controversial is whether women benefit in the same way as men.  When it comes to preventing another stroke or heart attack (known as ‘secondary prevention’), a key study, the Jupiter trial, found that taking rosuvastatin cut the recurrence rate in men and women.

As Kausik Ray, professor of cardiovascular disease prevention at St George’s University, London, points out, the five-year study ‘was so successful at reducing the incidence of deaths it was stopped after two years’.  ‘It found that healthy women at risk of heart attacks benefited significantly as much as men from taking statins.’

However, Dr Kendrick points out that while the recurrence rate dropped for both genders, the death rate dropped only for men.

As well as preventing a second heart attack or stroke, statins are also increasingly being used as ‘primary prevention’ — before there’s any sign of heart disease, let alone a symptom such as angina or a heart attack.

Here, the picture about the benefits for women is less clear.  A major review by the Cochrane Library (a highly regarded research organisation) said there was no evidence for using statins for primary prevention unless the patient was deemed at high risk of cardiovascular problems.

The review also pointed out most of the trials were conducted on white, middle-aged men.

So we can’t necessarily assume the findings will apply to older people, who may be at greater risk of adverse effects, and women, who may be at lower cardiovascular risk (thanks to their better lifestyles, oestrogen — which protects the heart — and their naturally higher levels of ‘good’ cholesterol).

For instance, when researchers from Harvard Medical School re-analysed eight major studies in 2007, they concluded there was no evidence statins worked as primary prevention for women.  ‘My view is that statins are, for women, completely useless for primary and secondary prevention,’ says Dr Kendrick.

However, Professor Ray disagrees, pointing out that in the Jupiter trial, which was published in the New England Journal of Medicine, 40 per cent of the nearly 18,000 participants were women.

‘The evidence clearly shows that women at risk of heart disease benefit to a similar extent as men, though the number of women in trials is small,’ he says.


‘It's difficult to monitor fatigue — you can’t measure it like cholesterol,’ says Professor Ray.  ‘The latest study is useful, but it is not going to change what we do.

‘Fatigue is a common symptom, especially in women, but can be due to other causes.

For example, you may have an underactive thyroid and in premenopausal women fatigue could be related to anaemia. These conditions are often not picked up.’ 

Dermatologist Dr Fenton points out that tiredness could also be a side-effect of the lifestyle measures many implement when prescribed statins.

‘Losing weight, taking up exercise and restricting a diet by eating less red meat can all cause tiredness. It’s vital to check iron levels.’

Even if the fatigue is linked to statins, don’t stop taking the drug automatically, especially if you’re at high risk for future events, e.g., you are diabetic.

‘If you have a strong family history of heart disease, and a poor lifestyle, or have multiple risk factors, putting up with fatigue may be more sensible than being at risk of heart attack,’ says Professor Ray.

‘You need to discuss this with your GP.’


‘You can certainly try taking them in a different way,’ says Professor Ray.  ‘For example, I’d recommend you take a drug holiday, under medical supervision. Stop taking your statin for a week (which is how long it will take to clear your system) and then see how you feel.’

‘Or you could ask to be swapped to a long-acting statin, such as rosuvastatin, a 5mg twice-weekly tablet, which may suit your body’s digestion.’

Statins have been linked to low levels of co-enzyme Q10 — a natural compound found in cells which is important for turning glucose into energy.  ‘This may cause tiredness, but you can’t measure levels in the body, so you can only see if taking a supplement helps by trial and error.  'It can’t hurt and might help,’ says Professor Ray.


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