Friday, October 07, 2005

Allergies, allergies, everywhere... but very few are real

About a sixth of teenagers think they have a food allergy - but only one in 50 actually do. Obviously, teenagers are often a little neurotic, but who can blame them when the media is full of stories about how one thing or another is bad for you? Sickness becomes a self-fulfilling prophecy, or one bout of mild ill-health is immediately linked to something they've come into contact with which was innocent.

Teens' allergy fears 'mistaken', BBC News, 7 October 2005

School meals and health

Children who eat school meals are at least as healthy as those who bring meals in from home, according to new research. For all Jamie Oliver's attempts to present school dinners as poison and only fit for pigs, they are nutritionally okay - not brilliant, but perfectly adequate in most respects. Given that most office workers are happy with a sandwich and a pack of crisps for lunch, our children seem to be no worse off than their parents.

Pupils 'healthier on school food', BBC News, 5 October 2005

I've written quite a few articles now on school meals for spiked:

Making a meal out of school dinners
Jamie Oliverís campaign for better grub for schoolkids promotes modern prejudices about food.

Hard to swallow
Jamie Oliver's hit TV show Jamie's School Dinners seemed to endorse some 'porkies' about modern food.

The Dinner Lady
Jeanette Orrey's practical cookbook is spoiled by the half-baked prejudices of the Soil Association.

Fat chance of making kids healthier
Thereís no need for the government to micromanage school meals.

Thursday, October 06, 2005

Rationing salt

A report published this week suggests that people in Britain consume too much salt, and that reductions in salt intake could cause a significant reduction in cardiovascular disease. Why 6g? A Summary of the Scientific Evidence for the Salt Intake Target, produced by the UK Medical Research Council (MRC), argues that a reduction in salt intake from current average levels of about 9.5g per day to the government's 6g per day target would lead to a predicted 13 per cent reduction in stroke and a 10 per cent reduction in coronary heart disease.

One of the report's authors, Dr Susan Jebb of the MRC, said: 'It is important for people to understand the links between salt and high blood pressure and to recognise the importance of reducing salt intake as part of broader lifestyle changes to decrease the risk of heart disease and stroke.'

While a link between salt intake and cardiovascular disease seems plausible, there is little direct evidence to support this report's assertion. High blood pressure is a well-known risk factor for heart disease and strokes. Reducing salt intake seems to lower blood pressure for many people, although for some people it has no effect whatsoever - and for a few, leads to an increase in blood pressure.

However, little research has been done into the direct effect of salt intake on the risk of ill health. What we do know is that the human body is very adept at regulating salt levels in the blood so that excess salt is excreted. This capacity to adjust salt levels has been crucial to our ability to cope with changes in temperature and diet, and our ability to adapt to living in a very wide range of different climates. It seems that the government and medical researchers would prefer to downplay this sophisticated mechanism in favour of salt regulation by guideline.

Moreover, blanket advice to cut salt intake may even cause harm. Sudden changes in temperature, due to a heatwave, exercise or travel to a hot country, can cause those accustomed to milder temperatures to suffer sodium deficiency. The current obsession with cutting salt intake may increase this risk.

The data linking salt intake with health is contradictory - and if there is a positive benefit, it is likely to be small. Reducing salt may help the seriously hypertense, for whom any means of reducing blood pressure is beneficial. For the rest of us, reducing salt in our diet is more likely to lead to bland food than better health.

Why 6g? A Summary of the Scientific Evidence for the Salt Intake Target, Medical Research Council, 3 October 2005

The (Political) Science of Salt, Science, 14 August 1998