The 52-year-old actress, famous for playing Mel Owen in the BBC soap as well as starring in New Tricks, opened up in a new interview.
She told Closer that she’s cut out alcohol after becoming a “lightweight” during the menopause and couldn’t have two drinks without getting “hammered”.
Tamzin explained: “Let’s just say I put on a lot of weight when I hit the menopause – over a stone.
“I eat a lot of food and I’ve got very high metabolism, but I could definitely tell I was heavier.
“I’ve never been one to diet but, when I stopped drinking, I lost the stone I’d put on and instead craved goodness, like fresh salads and juices.”
The star explained that she embarked on a health overhaul after filming the BBC series Freeze The Fear with Wim Hof last year, where celebs competed in sub-zero temperatures.
Tamzin said she didn’t drink for six months – even on her birthday – saying: “I felt amazing.”
The actress joined EastEnders as Mel in 1998 and went on to appear in more than 600 episodes of the soap.
She went on to star as Sgt Jo McDonagh in Red Cap and DCI Sasha Miller in the drama New Tricks.