Monday, August 30, 2010

The alleged fast-food/diabetes link

The British article excerpted below is typical of what one reads about fast food causing diabetes. The connection seems to be almost an article of faith. Yet when I looked at the evidence a couple of years ago, I could not find anything like conclusive evidence of an obesity/diabetes link, let alone a fast-food/diabetes link.

Let me state the obvious: Most fat people don't get diabetes and you can find lots of non-obese people in any McDonald's. Neither of those things would be true if fast food caused diabetes via obesity.

What has happened here, I suspect, is the usual epidemiological inattention to the direction of causation. It is true that those who already have diabetes do benefit by weight-loss and altering their diet but that does not mean that their diet caused the diabetes in the first place.

So what has caused the diabetes upsurge? At a guess: An interaction between genes and inactivity. Or maybe the increased stress of life in an increasingly lawless society. Or maybe both. But the research to find the real cause will not get done until this stupid obsession with fast food is abandoned. Don't hold your breath

The first thing you see when you enter Mayday University Hospital, Croydon, is a Burger King concession next to the main reception desk. If you don’t fancy that, there is an Upper Crust, and the shop opposite has a huge display with a buy-two-get-one-free offer on packs of Revels, Maltesers and Skittles. Bags of custard-filled mini-doughnuts were half price - but they’re all sold out now.

It is a depressing scene, not least because Mayday was the focus of a recent installment of The Hospital - a hard-hitting, five-part Channel 4 series examining the immediate and long-term effects of teenage obesity, alcoholism, violence and sexually transmitted infections. They are problems which, say health experts, are in danger of crippling the NHS.

The episode at Mayday looked at the impact of diabetes, particularly the obesity-related type 2 diabetes. The TV programme followed consultant diabetologist Dr Richard Savine and his team as they struggled to convince young sufferers to take responsibility for their health.

Speaking today, Dr Savine sums up the problem. ‘When I qualified it was unheard of to find a type 2 diabetic under the age of 40. Now we are seeing teenagers with the disease. 'They have diabetes because they have been fat since they were five years old or younger. In 20 years these people will get heart disease, be going blind, suffer strokes and need dialysis. 'And a large proportion of them will not survive, no matter what we do.’

'When I qualified it was unheard of to find a type 2 diabetic under the age of 40. Now we are seeing teenagers with the disease. They have diabetes because they have been fat since they were five years old or younger'

Watching nurses and doctors at the hospital - where one in five patients has diabetes - tuck into burgers and double choc-chip muffins, it is not hard to see why, with the best will in the world, their words fell mostly on deaf ears....

So what can be done? ‘We need to educate,’ he says. ‘Children are growing up with a skewed idea of what healthy eating is. ‘We need to get them to understand it isn’t normal to eat pizza or kebabs three times a week. And many patients see their health as something that doctors look after when it goes wrong.’

How does a Burger King in the hospital reception fit into that message? ‘Most patients will be fed hospital food, which is now very good,’ he answers. ‘It doesn’t matter whether the burger bar is in reception or next door - if a family brings junk food to a diabetic in hospital, you have already lost the battle.’

Of course, Mayday is not alone. Out of 170 NHS Trusts, 40 rent space to chains including Burger King, Subway and Upper Crust.


The toxic truth about vitamin supplements: How health pills millions take with barely a second thought can do more harm than good

Four years ago, I began taking the much promoted glucosamine supplement after hurting my knee in a skiing accident. Glucosamine is made from shellfish and is widely believed to promote joint health - the theory is that it speeds up the production of the protein needed to grow and maintain healthy cartilage.

Although there's no clinical evidence of its effectiveness, my GP said it might help rebuild the damaged cartilage and improve my joint strength. I didn't hesitate, and immediately started taking the recommended dose, 1,500 mg a day.

Not long after, I found I needed to go to the lavatory far too often - sometimes more than five times a day. I had abdominal discomfort, bloating, gas and my stools were dark and tarry. I self- diagnosed IBS.

My GP prescribed drugs to relax the bowel muscles, but they didn't help. Then, early last year, I ran out of glucosamine and didn't restock. My knee was better and I was taking fish oils, which were being promoted as the new miracle supplement for joints.

Within a few days, my bowels returned to normal and remained so until, after another ski accident damaging the same knee in March this year, I began taking glucosamine again.

Within a week my 'IBS' had returned and I made the link. I researched glucosamine and found that side-effects include diarrhoea and loose stools. I stopped again and, hey presto, everything's back to normal.

Sales of health supplements have soared in recent years, with 40 per cent of Britons taking them. It's such a huge market that manufacturers spend around £40 million a year just telling us about their products.

As supplements are either made from natural substances or mimic substances produced by our bodies, many people, like me, assume they cannot do any harm.

But we're wrong, say health professionals. They point out that the health supplement industry is unregulated, which means manufacturers are not required to list potential side-effects - nor do their products have to go through costly clinical trials.

There are a handful of exceptions, such as folic acid, which is recommended for women trying to conceive. If you take a tablet of 400 micrograms (mcg) strength to help with conception, it is classed as a food.

But increase the dose to 5 mg (to treat anaemia and other conditions) and it becomes a medicine, requiring a licence. Otherwise, there are no checks and balances to protect consumers. And this worries experts.

'Health supplements can produce ill effects,' warns Anna Raymond, from the British Dietetic Association. 'People take supplements randomly, but they can be toxic if taken with some medicines or in high quantities.'

Indeed, glucosamine has been linked to the death of one man. In 2004, Norman Ferrie, a 64-year-old engineer from Dundee, died of liver failure within weeks of taking the supplement. 'The liver had been normal and something had attacked it,' gastroenterologist Dr John Dillon, of Ninewells Hospital, Dundee, told the inquest in 2008. He said there had been two other cases involving extreme reactions to the widely used supplement.

'Increasingly, people are being taken in by the prospect of a magic pill that will make them healthy,' says Dr Dillon. 'Most people don't know that glucosamine and other supplements are only licensed as a food, but are sold as a medicine. 'It would seem fair to ask manufacturers of supplements to list serious risks.

'Everything we need can be got from a healthy diet. The vast majority of health supplements are a waste of money. People feel fluey and start taking supplements they don't need. They could end up with hypervitaminosis, caused by excessive amounts of supplements.' This can lead to vomiting, lethargy and even renal failure. 'The only time a person should take a supplement is if a doctor recommends it,' adds Dr Dillon.

But even taking supplements on doctors' recommendations is not risk free. Last month, it was reported that taking calcium supplements - often prescribed for osteoporosis - could raise the risk of heart attacks by 30 per cent.

And it's not just the main ingredient than causes problems. Another risk is having an allergy to one of the constituents of a tablet, such as a binding agent or the gel coating, says nutritionist Dr Carrie Buxton, from the Health Supplement Information Service.

Despite the concerns, the Food Standards Agency says legislation on supplements is adequate. So, what can you do to ensure your safety? Dietitian Anna Raymond advises anyone who starts taking supplements should tell their GP.

More here

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