You've got a shelf full of the latest diet books, from the Atkins to the Zone.
You're used to sitting at the dinner table gloomily pushing steamed fish around your plate while everyone else tucks into pizza.
You've never been happy with your weight – and to you, dieting is a way of life.
But is it one that you'd like your kids to follow?
When we spend weeks living on maple syrup, cutting out carbs or swigging grapefruit juice after every meal, we're also pushing some dangerous ideas. We're teaching our children that dieting, rather than healthy eating, is normal. That a quick fix is better than a long-term change.
And that we don't really believe that what's on the inside counts for much – at least, not when it comes to Mummy's muffin top.
Sarah, mum to two daughters aged seven and three, experienced first hand the effect that a parent's dieting can have on children. She decided to try the Dukan diet, a strict high-protein, no-carb regime.
"I was worried about the effect it would have on the oldest one," she says. "Because we always try to eat as a family, when I started opting out or was eating something different, she wanted to know why.
"At first I said it was because I was fat and needed to lose weight but that really upset her. She got tearful and said she liked me as I was and she didn't want me to change.
"I realised that speaking like that wasn't good in front of her because she had in the past - and did again - asked if she was fat.
"It was a graphic illustration of how vigilant you need to be about the ways you speak to kids - especially girls - about diets and food."
Mary George, of eating disorders charity Beat, says: "Negative attitudes towards shape are so contagious.
"Saying: 'Does my bum look big in this?' may be flippant, but can stay with a child.
"In this day and age, we are bombarded with comments about individuals. It seems to be fine to criticise people's body shape and size - and it's not right."
And she says that it's not just mums of girls who need to watch what they say. "Boys are under just as much pressure from all those celebrity role models who are 'ripped' and have a six-pack."
Of course, there's nothing wrong with losing excess weight for the good of your health.
But do it sensibly – not just for your own sake, but also for your children.
Make sure that they see you're making positive changes for the right reasons.
Sarah decided to talk to her daughter again about healthy eating. She says: "We also discussed the differences between adults' bodies and what they need to eat and exercise, as opposed to kids' growing bodies.
"She never really questioned it again and she eats well and healthily and has a good appetite.
Mary advises: "Whoever prepares the food in the household needs to provide the whole family with a balanced meal that doesn't send out the wrong messages.
"A mother sitting down to a bowl of lettuce can do that. If a child has a predisposition to developing an eating disorder, that kind of behaviour can contribute towards it.
"Celebrate the person within. It's so important to build up children's self-esteem and get them thinking positively about these issues."
Despite losing two stone on the Dukan diet, Sarah's now decided to ditch it in favour of healthy eating and exercise. "It was a drag always having to think about what I was eating and making something different to what the rest of the family was having," she says.
"Now I'm just eating healthily and have started running. My family has been really supportive – particularly my eldest, who is always encouraging me to go out for a run, especially if I say I don't think I can face it.
"She's always saying: 'You can do it, mummy.' I'm really pleased that she gets to see me being active and exercising."
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