Waistline should be half your height

apple_measure_tape_1600_wht_13129There is now further evidence on this from research carried out by Cass Business School at the University of London. It claims to be the first study to analyse official health records to measure the impact on life expectancy on obesity as measured by the ratio between your waist and height.

This is clearly not true as I posted about this in May 2013 describing research at Oxford Brookes University which also looked at the Health & Lifestyle survey, which goes back to 1984, and the Health Survey for England which studies 8,000 people every year.

Leaving these academic institutions to fight it out the results from both studies have the same message: your waistline – as measured at the narrowest point without breathing in – should be half your height or less. So a person who is 5′ 10″ should have a waist of no more than 35″, and a person who is 5′ 4′  have  a waist of no more than 32″.

If a man expands his waistline to 60% of his height he loses 1.7 years of life and a woman doing the same 1.4 years.

Dr Margaret Ashwell, a co-author of the study, said the rule applied regardless of a person’s age or ethnicity. Dr Ashwell first popularised the discovery that apple-shaped obesity is more dangerous than pear-shaped obesity in 1996 (see post: “What fruit is your bum“) because of the amount of central fat in the body which affects vital organs causing heart problems and diabetes unlike fat on thighs and hips.

She said people who rely on their body-mass index (BMI) live on false hope. Using the waist;height ratio puts 69% of the population at risk compared to 56% if you use BMI.

But whether adopting this as the preferred measure will make any difference is anybody’s guess. GPs, who recently attacked childhood obesity welcomed the findings but thought it was unclear whether “worrying people about their weight actually motivates them to make a long-term commitment to lifestyle changes”.


Health predictor? Use your your tape measure

figure_measure_1600_wht_5484Forget bmi (body mass index) as a predictor of your health and well-being, particularly the risk of diabetes and heart disease.

It’s long been doubted as it takes no account of muscles and definess any well-built athlete, serviceman, or similar person as overweight.

As an example the Times compared Arnold Schwarzenegger and Danny Devito. Both have the same bmi but Arnold has a waist-height ratio of 0.47, Danny’s is 0.71.

A far better predictor is your waist-height ratio. The scientists who carried out the study say GPs should be telling people to keep their waist circumferences to less than half their height.

 Researchers at Oxford Brookes University looked at the Health & Lifestyle survey, which goes back to 1984, and the Health Survey for England which studies 8,000 people every year.

Death rates were low for the 10% of people with the lowest waist-height ratios and rose steadily as the ratio increased. People with waists 80% of their height at age 30 lost about 20 years of life.

While bmi shows a similar trend it’s not as strong as using the waist-height ratio.

And for apple-shaped people bmi may give false re-assurance as central fat is more dangerous than fat on the hips. See something I blogged elsewhere: Apples & Pears – What fruit is your bum?