How to embrace a diet for life These three women's regimes differ wildly, but they all agree on one thing - a diet is for life not just post-Christmas. Lindsay, 35, is an actress. She is single and lives in London Until my early thirties I'd never had a problem with my weight - I was one of those lucky girls who could eat what they wanted and still stay slim. At about 32 I noticed I was starting to get rolls of fat around my middle. I didn't like it but couldn't seem to motivate myself to do anything about it. Then in March 2010 I went on holiday with a group of very fit, slim girl friends and ended up feeling really self-conscious. I just wanted to stay on my sunlounger and cover up. I hadn't weighed myself for a long time, but when I got home I did, and I was shocked to see I was nearly 12st. I'd put on several stone since the last time I weighed myself. I'm 5ft 9in, so I wasn't seriously overweight, but I felt miserable. I called a friend who'd recently lost a lot of weight and she told me that she'd been on a blood-type diet. The diet, which was developed by a naturopathic doctor, encourages people to eat certain foods and avoid others based on their blood type. The premise is that your blood type affects your digestive system. My friend said it was easy to follow and the results were quick, which was what I wanted. I booked an appointment with a nutritionist who specialised in the diet, and after a blood test she told me I was O positive. Luckily, this is one of the more 'user-friendly' blood types, and the diet I was put on was quite straightforward - lots of lean meats, poultry and fish, and no dairy products, beans, cereals, bread, pasta or rice. Other blood types have to follow stricter diets. For example, if you're blood type A you're supposed to avoid meat altogether. Now for breakfast I have fruit and soya yogurt sprinkled with flaxseed oil, which is high in omega-3. I eat lots of red meat and liver, which is apparently good for my blood type. I also swap potatoes or pasta for sweet potato, which has a lower glycemic index. Snacks are fruit or a handful of nuts. I love the fact that there's no tracking of calories or fat, as that would drive me crazy. I'm also allowed two small portions of carbs a day, although I usually only eat one. I try to eat any carbs at lunchtime, though, as my nutritionist told me that eating carbs close to bedtime means they're more likely to be stored as fat. The only alcohol I drink now is red wine as my particular blood group means that I need to avoid things high in acidity, such as white wine. The results were quick. Within six weeks I'd lost nearly 2st and had dropped a dress size. It probably helped that my energy levels were so amazing that I was also hitting the gym every day. The great thing is that the weight has come off in all the right places - so I've still got my hourglass figure but with a smaller bottom and a flatter stomach. I know some people question the science behind blood-type diets, but it has worked for me. Nearly three years on I have kept the weight off and now weigh 10st 4lb and am a size 10 to 12. I stick to the diet 99 per cent of the time but if I feel like having pizza or a piece of cake then I will - I just get back on the diet the next day. I honestly don't feel as if I'm on a diet - to me it's a lifestyle change, and the only motivation I need to keep going is knowing that I look and feel great. Typical day on a blood-type diet Breakfast: Fruit or yogurt with linseed or flaxseed oil Lunch: Meat or fish with sweet potato or a piece of spelt/rye bread and lots of vegetables Dinner: Any kind of red meat or fish such as halibut or mackerel with broccoli or asparagus See: www.rejuv.co.uk THE RAW-FOOD DIET India Leigh, 43, is a food and travel writer. She is single and lives in East Sussex As a food blogger, I love learning about the way people eat, and about five years ago I started hearing a lot about raw food diets. The more I read, the more it appealed. Then, on holiday in California two years ago, I visited some of the local raw-food restaurants - and I loved the food, which was interesting and varied. But I still couldn't quite commit. I've been a vegan since 2001 and the thought of cutting out soups or stews was too scary. It was only when I started to gain weight a year ago that I felt it was time to give it go. Putting on weight was alien to me. I was far from fat - I am 5ft 3in and have always been about 8st - but last year my weight crept up to 9st, and I thought, 'I'm past 40 and I don't want to start that downward spiral into being overweight.' It was the kick-start I needed. I began looking up recipes online, bought lots of books on raw food, and in March this year started eating raw food only. The idea behind the diet is that raw is healthier because cooking changes food's nutritional content. I started with juicing. In the morning I'd juice spinach, kale, celery, cucumber and half an apple for breakfast. Sometimes I'd add carrots, broccoli or beetroot. I'd keep the leftover pulp for my lunch - if you mix it with pea protein it's delicious and tastes a bit like a cold porridge. As a treat I sometimes sprinkle it with goji berries. For my evening meal I'd put more pulp into a dehydrator. Once it has dried out you can make pulp into crackers or kale chips. Sometimes I would roll it between sheets of nori (which is dried seaweed) and add hummus and avocado to bulk it out, and that would be my evening meal. Raw-food meals can take time to prepare, but once I started to see results I knew I had to keep going. Within two months of starting the diet I'd lost a stone. Trousers that hadn't fitted me for a couple of years were suddenly baggy on me. But it's not just the weight loss that I'm thrilled about. The diet has given me so much more energy - now after a zumba class I sometimes go for a run. My muscle tone has improved drastically, too - my arms now have definition and my tummy is the flattest it has ever been. One of the things a raw-food diet has taught me is that my body doesn't need nearly as much food as I thought it did. I'll never eat cooked food again - the health benefits of eating a raw-food diet are just too good. Typical day on a raw-food diet Breakfast: Juice made from an assortment of fruit and vegetables Lunch: A paste made from sun-dried tomatoes, home-made hummus in nori with some avocado Dinner: Kale with pink Himalayan salt and olive oil with home-made tahini and miso dressing with tomatoes and alfalfa sprouts THE LOW-CARB DIET Liz McAreavey, 50, is the director of the Edinburgh Chamber of Commerce. She is divorced and has three children I first heard about home-delivered, low-carb diets from a close friend. She'd tried one and was evangelical about it, saying she'd lost weight and never once felt hungry. I was heading for 50 and really aware that I'd put on a couple of pounds. If I wasn't to fall victim to middle-aged spread I knew I needed to do something. I thought I knew the problem, too - I was eating a lot of bread and carbs and it was making me overweight and sluggish. I decided to give it a go and signed up to golower.co.uk . The premise of the diet is that your body burns carbs and sugars first; if you restrict those, your body will start burning through fat stores instead. Most people who sign up to home delivery get their food sent to them for a month, but I decided to do it for two weeks to get used to the new way of eating. After that I hoped to be able to go it alone. In the mornings I'd eat a special low-carb granola, lunch was a low-carb soup and my evening meal was a meat dish - something like lamb meatballs and lots of green vegetables. In two weeks I lost half a stone. I loved the fact that there was no portion control, no weighing of things. I then began to cook my own low-carb dishes. Occasionally I craved bread but if I did I'd just eat one with a low-GI content - rye or spelt. Rice and potatoes were out, so if I wanted a comforting risotto I'd simply eat grated celeriac. I also got used to eating big bowls of broccoli, green beans, cabbage and leeks, and lots of salmon, lamb and steak. I didn't feel as if I was on a diet because I was never, ever hungry. By the end of the first month I'd lost nearly a stone, and three years on I've kept the weight off. I do allow myself occasional treats - the odd square of dark chocolate or glass of wine - and if I'm at a dinner party I may well put a potato on my plate just to be polite. But to me this 'diet' is now a way of life. At 50 I feel more energetic than I did at 40 and I'm thrilled when people often tell me I look 10 years younger than I actually am. I feel the best I have ever felt. Typical day on a low-carb diet Breakfast: Special low-carb granola or nut-cluster cereal served with yogurt, blueberries and strawberries Lunch: home-made chicken soup or a pea and pancetta soup Dinner: Meat or fish with lots of green vegetables or Moroccan-style lamb meatballs See: www.naturalketosis.co.uk