Weight-loss jabs have been hailed as a pain-free, effective way of losing pounds. But it turns out they may be responsible for adding on a few pounds - to the price of meat.

Experts say the demand for protein from consumers on the jabs is one of the reasons behind an expected 10 to 20 per cent increase in the price of meat this year.

Oisin Hanrahan, the chief executive and founder of Tesco-backed supply chain platform Keychain, said several pressures including global insecurity and energy prices were contributing to the rising cost of meat.

But he added that rising demand was also a factor, driven by an emphasis on the importance of nutrient-dense protein for those eating smaller portions as a result of the effects of GLP-1 medication, or weight-loss jabs.

Mr Hanrahan said: ‘It wouldn’t surprise me if there was, say, a 10 to 20 per cent (increase) on certain meat items over the year.

'Increasing demand is also increasing price, and all those on GLP-1 medications know they need nutrient-dense, high-quality protein - and that is your beef, lamb, chicken and pork.’

Figures from analysts Worldpanel show inflation on fresh meat was at 14.5 per cent for the four-week period ending December 2.

Mr Hanrahan said chocolate, coffee, butter and fruit were among other products that had seen the most ‘eye-watering’ rises over recent months.

He urged consumers to be open to buying meat and other products on offer rather than going to the supermarket with rigid lists.

Millions of Britons taking the weight-loss jabs may have to stay on them for life, experts have warned.

Most users regain their weight within two years of stopping the treatment, much faster than traditional dieters, a landmark study found.

The analysis examined 37 studies involving more than 9,300 people and showed that weight returned rapidly, regardless of how much was lost.

A pound a month of weight was gained, with many returning to their original weight in 17 to 20 months.

Professor Susan Jebb, co-author of the study and adviser to ministers and the NHS on obesity said: 'Obesity is a chronic relapsing condition, and I think one would expect that these treatments need to be continued for life, just in the same way as blood pressure medication.'

GLP-1 drugs work by suppressing the feeling of hunger by mimicking the hormones released after eating, but withdrawing this hormonal 'fix' can leave users vulnerable to rebound hunger.