The good news is that as of yesterday I am no longer obese.

At my heaviest weight of 16st 3lbs and standing 5ft 10ins tall my body mass index came in at 32.5. As you know obesity begins at 30 on the BMI scale.

Due to an Herculean effort I managed to lose an entire stone. This was achieved by eschewing too much lager and not chewing too many chips. Sadly, even at 15st 3lbs my BMI of 30.6 still qualified as obese.

Then along comes Nick Trefethen of Oxford University's Mathematical Institute to move the goalposts. Mr Trefethen (whom God preserve) has postulated that the BMI, invented by some Belgian bloke nearly 200 years ago, requires tweaking because "it divides the weight by too large a number for short people, and too small a number for tall people".

The old formula is weight divided by height squared. The new calculation is 1.3 times weight divided by height to the power 2.5. Confused? Check your BMI on Mr Trefethen's website at people.maths.ox.ac.uk/trefethen/bmi_calc.html.

Thanks to this Oxford Mathematics Institute diet my BMI has gone down to 29.8 – not obese, merely overweight. I may have a pint of lager and a poke of chips to celebrate.

Among other news on the fat front, research shows obese drivers are more likely to die in car crashes. Check it out for yourself in the Emergency Medicine Journal. Basically, seatbelts do not work as well when strapped around a big fat belly. Another benefit of not being obese is that you will cease to be an object of pity and concern by the Westminster Health Minister Anna Soubry. This Conservative lady claims she can spot poor people in the street because they are usually overweight.

Ms Soubry says: 'When I go to my constituency, when I walk around, you can almost now tell somebody's background by their weight. When I was at school, you could tell the demography of children by how thin they were."

She adds: "There are houses where they don't have dining tables. They will sit in front of the telly and eat."

The problem is that the poor spend their low wages or benefits on junk food. The answer is don't get poor and don't get fat. Eat more lentils and save up to buy a dining table from Ikea.