Thanks to swimming for an hour a day and eating healthy food, Helen's feeling in the best shape ever.
On Monday, Helen posted on Instagram: "Very happy today for a whole month I have been so disciplined and focused and have really slimmed down and toned up :).
"I've gone from a curvy size eight to a very slim eight I'm only 5ft 3."
Helen, 23, added a picture of herself at a recent event in Manchester to show off her new figure. it was however taken before Helen dyed her hair a fiery red colour!
She continued: "Just felt a bit sluggish after Christmas and my main inspiration and motivator has been my youngest sister @jnflanagan who has lost quite a lot of weight and looks incredible.
"I have done it by being very disciplined but not depriving myself either of things I enjoy such as wine and chocolate."
"I have also been working every day for an hour my exercise has been swimming. It has been really really hard so I feel really proud of my self to have achieved this :).
"I have made sure I have kept my health in check by following @thegreengoddess and my mum has been very supportive. I Feel great and you get nothing without hard work."
The actress has been filling her Instagram feed with pictures of healthy food of late, and we're glad to hear that Helen's been allowing herself treats, too.
After all, life would be pretty rubbish with a bar of chocolate or two, right?
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