Winchester swimming instructor, Tessa Berry, has lost weight equivalent to a mountain of over 900 chocolate bars.

Tessa, from Alresford, nearly halved her weight as she shed eight and a half stone over 16 months.

The King Alfred's College graduate had reached a peak of 181Ž2 stone before she joined Weight Watchers in February last year.

Through sheer determination, she achieved her target weight in less than a year and a half.

"It was incredible, when I made it," she said.

"It's one of those things where you think you'll never get there. I was in shock actually when I got on the scales. I didn't think I would achieve it that week and I couldn't believe it."

The 23-year-old, who studied sports and English at King Alfred's, was spurred on to shift the pounds by a friend who had had some success with Weight Watchers.

"It worked for her and I just agreed to go along. If you go with another person you are more likely to make yourself do it. So we started going to the Kings Worthy group for regular meetings."

The programme involved a drastic re-think of her diet and exercise regime. She began to work out, and was motivated to eat more healthily by the ritual weekly weigh-ins.

The target weight, set according to height and age, drew ever closer with each half-stone loss flagged up by the Weight Watchers team.

"I had a lot of moral support from others in the group trying to lose weight," she said.

"There were up to 40 people at each weekly meeting and I'd really like to thank Lisa Dunn, the group leader, for her support. My friends were really impressed and happy for me, and I had lots of encouragement all the way through."

Tessa, who teaches at a swimming school in Winchester, and part-time at River Park Leisure Centre, was relieved to have seen the diet through to its goal. Her challenge now, she says grimly, is to stick to the regime and keep the pounds off.

* Hants and West Susses Weight Watchers manager, Katie Oakley, has been congratulated by TV chef, Antony Worrall Thompson, on a successful year in which her members have shed over 70,000 lbs.