Friday, March 13, 2009

Women, keep drinking

Why was a flimsy study apparently showing a link between booze and breast cancer so uncritically accepted? The woman who headed the study is a fraud and a liar whose results were the opposite of what she claimed

For over a decade, a constant stream of studies has warned women who drink that they run an increased risk of getting certain cancers, particularly breast cancer. But this steady stream of anti-drinks advice last week gave way to a global torrent when two new studies about the link between drinking and cancer in women received huge, and typically uncritical, international media attention.

The study that attracted the most attention is sponsored by Cancer Research UK and was published in the Journal of the National Cancer Institute. The lead researcher, Naomi Allen from Oxford University, told the Guardian: ‘Given that this is the largest study in the world to look at this, it’s clear that even at low levels of alcohol consumption, there does seem to be a very significant increase in cancer risk, and most women are probably not aware of that.’

Allen came across with even scarier news for Americans, telling the Washington Post that the ‘take-home message’ was this: ‘If you are regularly drinking even one drink per day, that’s increasing your risk for cancer [since] there doesn’t seem to be a threshold at which alcohol consumption is safe.’

One can’t help but wonder just what Allen herself has been drinking in the Senior Common Room at Oxford. After all, her public pronouncements, her recommendations to government, and the reports about her study in the media are certainly not supported by her results.

First, Allen’s study is an observational one, based on data from the UK’s Million Women Study, which is a study about the association between Hormone Replacement Therapy and cancer and heart disease. Allen’s study comes from self-reports about the drinking habits of women in that study.

This means that the study, as an observational study – the weakest kind of epidemiological endeavour and certainly nothing close to the gold standard of a randomised controlled trial – is inherently unable to draw any causal conclusions about a link between drinking and cancer.

Second, the study fails to meet even the most basic requirement of science – that is, being able to validate its measurements – since it is entirely based on the women’s self-reports of their recollection of their drinking. None of these reports was checked and the authors can make no claim about how reliable they are. No one knows how much or how little these women really drank since no one bothered to measure it. This makes any conclusions based on such ‘evidence’ just a tad dicey. At its foundation, therefore, the study can’t warrant that any of its data about the key fact – the drinking habits of its subjects – is accurate. However, the worst is yet to come.

Third, the study is full of significant puzzles that suggest that its results are unreliable. For example, it reports that the incidence of all types of cancer studied in its non-drinking subjects was 5.7 per cent compared with 5.3 per cent for those subjects who had at least a drink a day, and up to 14 drinks a week. In other words, not only was there no dose-response in terms of cancer risk, but teetotallers had a higher population incidence of cancer than those consuming up to 14 drinks a week! Even those women in the study who drank the most (15 or more drinks a week) had a cancer incidence of 5.8 per cent, which is virtually identical to those who drank nothing. But this particular take-home message somehow escaped Allen’s notice, and that of the media as well.

Fourth, the study looked at 21 types of cancer incidence. Of these, it found statistically significant associations between drinking and only four types of cancer. Moreover, these associations were barely significant. The association with breast cancer, with by far the largest number of cases in the study (almost 22,000), was non-significant. Therefore, of the cancer-drinking correlations examined, virtually none was statistically significant.

What is the real take-home message of this study? Perhaps it should be to avoid drinking policy advice produced by Oxford epidemiologists.


Prince Charles accused of 'outright quackery' over detox food supplement

Prince Charles has been accused of ‘ exploiting a gullible public’ by putting his name to a detox treatment. Professor Edzard Ernst, Britain’s top expert on complementary medicine, said the 10 pound Duchy Herbals Detox Tincture relied on ‘ superstition and quackery’ rather than science. Nicknaming the range ‘Dodgy Originals’ after the Prince’s Duchy Originals brand, Prof Ernst said that using herbal potions to detoxify the body was ‘implausible, unproven and dangerous’.

The 10 pound tincture was launched last month as part of the Prince’s range of luxury organic products. Customers are advised to add a few drops of the dandelion and artichoke solution to a glass of water twice a day. Combined with a balanced diet, it is claimed, the product will help the body cleanse itself of ‘toxins’ and aid digestion.

But Prof Ernst, a complementary medicine researcher at Exeter University and a former homeopathic doctor, said there is no evidence that the tincture works. He said: ‘I know everything about artichoke that there is to know. There is a hint it might lower cholesterol to a very minor degree, but that’s all. ‘And there is nothing to know about dandelion. They say they have produced it to the highest standards, and that may be so. But high quality nonsense is still nonsense.’

The professor warned that detox products could be dangerous if they were viewed as a ‘quick fix’ to unhealthy habits. He said yesterday: ‘Prince Charles contributes to the ill-health of the nation by pretending we can all over-indulge and then take his tincture and be fine again. 'Under the banner of holistic and integrative healthcare he promotes a “quick fix” and outright quackery. ‘Prince Charles and his advisors seem to deliberately ignore science and prefer to rely on makebelieve and superstition. ‘Prince Charles thus financially exploits a gullible public in a time of financial hardship.This comes from somebody who should know better and from somebody who arguably should not be deluding the nation and contributing to its ill-health.’ Prof Ernst added that those who do over-indulge should simply drink lots of water, take exercise and get some rest.

The Duchy Originals website states: ‘HRH The Prince of Wales… believes poor health does not exist in isolation, but is in fact a direct consequence of our lifestyles, cultures, communities and how we interact with our environments. ‘He is passionate about adopting an integrated approach to health, as well as exploring how safe, proven complementary therapies can work in conjunction with mainstream medicine.’

A Duchy Originals spokesman said the tincture satisfied ‘all of the relevant sections of both UK and European food laws’. Andrew Baker, the firm’s chief executive officer said: ‘It is a natural aid to digestion and supports the body’s natural elimination processes. ‘It is not – and has never been described as – a medicine, remedy or cure for any disease.’ He added: ‘Duchy Herbals Detox Tincture contains globe artichoke and dandelion which both have a long history of traditional use for aiding digestion. ‘We find it unfortunate that Professor Ernst should chase sensationalist headlines in this way rather than concentrating on accuracy and objectivity.’

Nelsons Organic Pharmacy, which makes the tincture for Duchy Originals, said that artichoke and dandelion had been used for hundreds of years to aid digestion. Its chairman, Robert Wilson, said: We do not believe this product encourages ill-health through over-indulgence.’


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