DIETICIANS HAVE revised the previous formula governing the supposed relationship between calorie intake and weight loss – meaning that it’s now twice as hard to lose weight as had been previously thought.

The previous rule of thumb suggested that cutting 500 calories from the daily diet would translate into the loss of 1lb per week – but dieticians say that rule is too simplistic and doesn’t take account of the effects of dieting itself.

Although reducing the calorie intake does prompt weight loss, the formula doesn’t account for the fact that cutting your calorie intake also means your metabolism slows down: meaning the very act of dieting itself makes it tougher to shift weight.

The Guardian quotes Dr Kevin Hall as telling an American conference:

If you change calories, your metabolism slows down and eventually you reach a plateau. [...]

If you want to lose 10lb of weight eventually, you need to cut 100 calories a day from your diet. You will get halfway there in a year, but then plateau after three years.

Hall and other dieticians have reexamined the relationship between calorie intake and weight loss, and used a rebalanced formula to create an online calculator which hopes to give a more realistic projection of how cutting down on food might impact your weight.

The calculator is designed to be used by GPs, but is simple enough to be of use to the general public – though anyone looking at getting medical advice on losing weight should of course consult their own doctor.

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