One frightening piece of research shows that 79% of women think that their social lives would improve if they were as thin as Calista Flockhart (star of Ally McBeal). Calista Flockhart is 5'6" tall and is reputed to weigh just 100lb (20% less than the minimum recommended weight for a woman her age and height). She's also reputed to be a size 2. And her co-stars on the show are all competing to match her in thinnness - peer pressure at work, even among intelligent and highly-paid people.

The average model is at least 5'9" tall and generally between 10lb and 25lb below the minimum recommended weight for their age and height. Exceptions such as Cindy Crawford are rare enough to be noticeable.

Every newsagent has racks of magazines showing men with washboard abs, when the reality is that most men don't have six-packs. And in truth the classic six-pack is extraordinarily difficult to achieve. Even very fit men often don't achieve this because it demands a very low body fat percentage which can only be achieved by focusing on very little else. In other words, if you see a guy with an honest-to-goodness six pack the chances are he's as obsessive as any teenage girl with an eating disorder.

The first step is to know what's normal. More to the point, it's worth knowing that weight alone is a poor indicator. Luckily these days it is fairly easy to get a body fat measurement - most fitness clubs and gyms will do this for you, it takes a few minutes, and it gives you a fairly accurate reading of your body fat percentage. Men should achieve between 12% and 20%, women somewhere closer to 18% to 25% (lucky things). Your weight should probably be not less than 5% below the recommended weight for your age and height, and not more than 5% above - but be prepared to adjust this if (be honest, now!) you are genuinely big-boned, very fit (muscle is considerably denser than fat), or maybe you are petite or have a fast metabolism.

So, how do you actually change your shape, lose and control your weight?

It's like the old joke about how many psychologists it takes to change a light bulb. You have to want to change. If you are below the weight band but feel you are too fat, please stop reading this forum now and seek professional advice. I have seen anorexia at first hand, and it is distressing. If on the other hand you're a gym rat and want to get bigger still, well keep off the steroids and get a personal trainer. This is for the rest of us.

Diet

A great philosopher once said, 'Diet is just 'die' with a 't' on it.' (It was Garfield the cat). But, hey, these days diet is much more fun than it was in the carrot-juice-and-three-lettuce-leaves days. If you want to lose weight, many people swear by the Montignac food combining system, whereby certain food groups may not be combined in a single meal. Although recent research shows that this may actually be less effective than the old fashioned EH system (where you Eat Half the normal quantity), it has the very definite plus of being interesting. Even if it's only half as effective, the fact that it's easy to stick to without monotony makes it a strong contender.

One other diet which can produce dramatic effects fairly quickly (and sustainably) is to focus on fat reduction. Stop using butter, margarine, drink black tea and coffee, have toast instead of cereal with milk, reduce dairy product intake. Don't overdo it, a certain amount of fat in the diet is essential, but so many modern foods have added fat that cutting out the fat which you add can have an immediate and positive effect.

Current thinking indicates that five or six light meals spread over the day is better than the traditional three square meals of old. This is not an excuse for grazing (you can kiss your waistline goodbye if you sit on the sofa eating Pringles and watching the telly of an evening), but it is a good idea to have some healthy snacks to prevent the body kicking in its built-in emergency systems. One reason so many weight-loss diets fail is that the body responds to reduced food intake by slowing down the metabolism - the 'famine response' - which works against you, especially as this also means that the food you eat may be laid down as fat as a buffer against the perceived famine conditions. Which also probably wasn't quite what you had in mind. So break out the crudités, dip them in houmous instead of Sainsbury's rather nice thousand-island dip, and enjoy.

Exercise

Oh my is this a thorny subject. Every year in January millions of people take themselves to the gyms and health clubs of the world as a New Year's resolution. And between five and six weeks later most of them have stopped going. Why? Because exercise is, of itself, boring. So the secret of a successful exercise programme lies not in the exercises themselves, but the combination, duration, environment and dedication.

There are two main sorts of exercise, resistance and cardiovascular, and both suffer from exactly the same problem: just as you're hitting a rut and getting bored with them, the effect hits a plateau and you stop making progress. There is a way round it, but you have to have a good gym. The secret of a successful exercise programme is as follows:

• Commitment. You have to mean it.

• Goals. Use the SMART technique (Specific, Measurable, Achievable, Realistic and Timed). So, set yourself a target of two pounds lost per week for one month, or whatever.

• Variety. You have no idea how boring it is running towards a mirror image of yourself. So ask the trainers in the club for suggestions - two minutes running at 7mph on the flat, one minute at 6mph on a 5% incline, repeated four times, for example. You are paying for their expertise; use it!

• Regular re-assessments. When you join most clubs they'll assess you. You can generally get a re-assessment any time just by asking, and they'll help you work out a new programme with new challenges and different exercises. If they don't, you're at the wrong place. Find a better gym.

• Just do it! You have to go, and keep going. Three or four times a week. Sounds like a lot? Well, it might be - but it's the same amount of time you probably spend keeping up with soap operas, and it's much better for you.

There are other things, such as buying really comfortable shoes (one shop locally has a machine which takes an imprint of your foot as you run) and enrolling in classes. Misery loves company, and you can't beat a good old-fashioned circuit for burning the calories.

So, to the two main forms of exercise:

Resistance Training

Resistance training is weight-lifting dressed up. It does good things for your self image (especially if you're a bloke) and it makes you more able to carry out everyday tasks, because you're that bit stronger. Much more importantly, resistance training builds bone density and thus helps combat osteoporosis.

What else does it do for you? If you are underweight, it helps you gain weight in a healthy way. And since muscle weighs more than fat it's more productive too. If you weight train you are less likely to injure yourself moving things around the house (unless, of course, you decide to pick up loaded wardrobes using your new-found strength) and it gives your partner a kick as they explore each new muscle.

The downside is, there are a lot of people who weight train seriously with the aid of drugs, most often steroids. These destroy your heart; Arnold Schwarzenegger has had open-heart surgery. He also illustrates the other downside - loss of flexibility. Be very careful to maintain full joint movement in your programme. Arnie reputedly can't tie his own tie anymore. But then, he can afford a man to do that for him. You might not get so rich.

Cardiovascular (CV) Training

This is the heading under which sweaty out-of-breath type exercises are grouped. Typical CV exercises include running (usually on treadmills), stair-climbers, rowing machines, cross-trainers and the like. Here's where you'll lose that tummy. You can do abdominal exercises (sit-ups, for those of us aged over 30) for the rest of your life and never achieve a flat stomach; fifteen minutes on the cross-trainer three times a week and you won't recognise yourself.

The common thread with CV exercises is that you burn energy, usually by using the legs (these are the easiest muscles to work, so a soft target for any serious calorie burning).

WARNING: If you are significantly overweight, or very unfit, and you set out to run a marathon on the treadmill, you might just end up in a wooden overcoat. Seriously. The use of a heart-rate monitor (available from about £30) is very strongly recommended. Also seek medical advice.

Mixed Training

If you really want to lose weight and get fit, go to the gym for at least an hour every other day and spend every second when you're not CV training, on the resistance machines at low weight. Do twenty repetitions at something you can lift reasonably comfortably then run to the next machine and do the same there. Your heart rate will stay in the weight-loss zone for the whole hour! Or, join a circuit training class. This is great - misery loves company.

Non-boring Weight Training

One Researcher has come up with a convincing argument why a little weight training is a good thing... and it doesn't have to be that boring.

I believe that a little weight training is essential - especially for the person who wants to lose a lot of weight. Don't think of weight training as something for the serious athlete. Muscle keeps the back straight (minimizes a potbelly) and holds the knee, shoulder, and hip joints in place. Besides, it burns calories 24 hours a day, whether it's exerting itself or not. So if you're just starting to exercise, be sure to work out those leg and back muscles - less chance of injury.

I first began weight training when I had to go to physical therapy for my shoulder. The therapist told me that strengthening the muscles around the shoulder joint would reduce the problems I had with it (kept injuring the tendon from repetitive motion). Haven't really had a problem since.

As for boring, repetitive exercise - I vary my workout from day to day. The gym I go to has TV's mounted on the exercise bikes, so I can work out and watch sitcoms. If I get tired of that, I go jogging, or work out on the stair stepper. I do spend a lot of time thinking while I'm exercising - especially when I'm jogging. They say exercise is good for relieving stress. This is because repetitive motion allows the brain to work out problems that it hasn't had time to think about while you're occupying it with work or what to eat for dinner...

Eat When you Need to Eat

One recurring theme in these postings is 'only eat when you need to eat, and don't eat more than you need'. In other words, your body will tell you what, when and how much you need to eat. However, it has been found that in many people with weight problems, the mechanism that tells you when to eat and when to stop has become defective. This means that you eat more than your body actually needs, which prolongs the problem. The 'defect' can be put right, though - without operations or pills or any other kind of medical interference. All you need to do is eat sensibly and exercise. 'Eat sensibly' means reasonable portions of foods that contain the nutrients (protein, vitamins, minerals, carbohydrate) that your body needs. As for exercise, it has been found that, if you exercise regularly, your body will regulate the 'I'm hungry' signals so that you only get hungry when you really do need to eat.

Putting it succinctly, bad eating habits cause the problem. Good eating habits and exercise can cure it. And one Researcher agrees...

I do notice that sometimes when I've eaten what looks like enough but I'm still hungry, if I don't eat more, the hungry feeling wears off. I do think you're right about habit.

Dance it Off!

Seriously, dancing around the house to some of your favourite tunes is very good way to obtain some exercise, and it can be done even whilst in the middle of household duties, such as ironing.

Another way to getting in some exercise when time is too short to go to the gym, is to tackle house cleaning with extra zest and look at it as a work out. It is remarkable how much your body works out when you do a solid hour's housekeeping ie, sweeping, scrubbing, hoovering, dusting, taking out the rubbish, changing the beds and so on.

A Gentle Eight- Point Plan

This nice and easy(ish) eight point diet plan seems to make a lot of good sense, coming as it does from the personal experience of a long-term dieter who has learned a lot from years of experience. (For non-UK citizens, 1 stone = 14lbs.)

1. Take it slowly. Weight loss of more than 2lbs per week is unhealthy. The more slowly you lose the weight, the more likely it is to stay off. 1lb per week is sustainable. If that doesn't sound much, it's nearly 2 stone in a year.

2. If you have a lot of weight to lose, break it down into small milestones, say, half a stone (7lbs). That way you won't get so depressed by how much weight you still have to lose. Give yourself a small, non-food treat when you reach each one.

3. Don't use food as a reward for sticking to your diet. It doesn't help.

4. Exercise as well as cutting calories. When you cut back on food your body reacts as if there's a famine, especially if you cut back hard. One way it does this is by slowing your metabolism, so your body burns fewer calories than it did. Exercise speeds your metabolism up again, helping you to burn off those calories. It also helps to get you fit!

5. Give yourself an incentive to lose weight. I'm paying myself £10 for every lb I lose, so I'll have £500 when I hit my target.

6. Allow yourself a weekly calorie total, rather than daily. One of the most common causes of ending a diet is a 'binge' eg, a party. You've broken your diet, so you might as well quit. A weekly calorie total allows you to party one day, then eat more carefully the next.

7. Don't think that a particular food type is forbidden (eg, cakes, biscuits, chocolate). It will only make that food more appealing and make the diet harder to stick to. Build a small daily (or weekly) portion of your favourite food (or drink if you're into a particular beverage - alcoholic or otherwise) into your diet.

8. Keep an eye on your measurements as well as your weight. As you exercise, you may develop bigger muscles, even if only slightly so. Muscle weighs more than fat, so it may look as if you're not losing as much weight as you would like. Use your measurements to check whether you're getting to the size you'd like to be.

A couple of dieting fallacies

• Some types of exercise burn weight off a particular body area: No. Exercise tones muscles, which makes that body area firmer and trimmer. Exercise burns calories, which helps you lose weight, but the weight loss is from all over the body.

• Exercise turns fat to muscle: This is impossible. Fat tissue and muscle tissue are completely different. As you exercise and lose weight, your muscles will firm up and the fat deposits will go down. The fat has not turned to muscle.

A Simple System

Here's a straightforward and simple enough approach to the problem of losing and then controlling weight:

I've recently had a huge overhaul in my life and re-evaluated my lifestyle. I have modified my diet and routines and the way to lose and control weight is to watch what you eat and, sadly, exercise. The food thing was the hardest - it's no good just eating salad etc - in cold weather you want something that will stick to your ribs - do a little research and find out which foods have low fat content and be creative - if you are exercising, the calorie content should be OK.

What I do is tend to have carbohydrates one day and proteins the next - very rarely the two together. Of course, there are occasions - so treat yourself, indulge once in a while but if you do, the following day, drink plenty of water and eat lots of veggies etc. There is an old addage:

Breakfast like a King
Lunch like a Lord
Dine like a pauper

This worked for my grandma, mum, my papa and is working for my sisters and me. This gives your body a chance to digest food before bed time.

Did You Know...

• Standing up burns more calories than sitting? And if you add in small movement (like tapping your foot, for instance), you burn even more calories.

• Medications can effect your metabolism? Birth control pills and shots are notorious for this, but other prescription medications can have the same effect. they slow your metabolism, so even if you do not eat more, you will gain weight because your body doesn't burn the calories as fast.

• Smoking effects your metabolism? Quitting smoking is one of the best things you can do for your body. After a period of time, simply the fact that you no longer smoke will give you more energy making it easier to exercise and burn calories. But, smoking actually speeds up your metabolism! So when you quit smoking your metabolism slows down, and the odds are very good that you will gain some weight, even if you don't turn to comfort foods. Don't lose heart: eventually as your energy level rises your metabolism will level out, and with exercise (which won't be so hard since you've quit smoking) the extra pounds (and then some!) will fall off.

• Diet pills, herbal diet aids, and 'miracle' products will not help you? Yes, you will see a drop in weight (short-term!!) if you use them correctly, but they do not change your lifestyle which is what you need to do to achieve long-term or lifetime weight management. There is no easy way to lose weight! However, it is a good idea to take a multi-vitamin, no matter how you change your diet. You may want to consult your doctor to find out what kind of vitamin is right for you, but giving your body enough of the basics it needs will ultimately raise your energy level, and more energy burns more calories. You'd be surprised at the specific functions some of those little vitamins and minerals provide!

• Breast feeding is one of the best ways to lose maternity weight? It's true! Most women have a negative body image after childbirth; they feel fat and flabby from what the baby left behind, and it's usually hard to exercise as they are stiff and sore from giving birth. don't be discouraged... breast feeding your baby will really make a difference in the post-partum weight you lose. A majority of women who breast feed after giving birth report losing all maternity weight within one to two months! And it's best for your baby, too!

Perspective!

No reasonable person would argue against the fact that these days too much emphasis is put on appearance, at least in the popular media. We're all under 'scrutiny' and there's a huge industry out there that preys on people's self images with all kinds of worthless and unnecessary products and systems supposed to make them more attractive. And the more insecure you are about your appearance, the more likely you are to try out these (expensive) products. People must be made to believe that there's something seriously wrong with them when there's not. It's an entire culture that seems to be created for the sake of profits, so... keep a sense of balance and perspective about weight. Too much fat is no good for the health. Too much obsession is no good for the soul either. We'll leave the final say to one Researcher who definitely wants us to keep a healthy sense of perspective.

I live in Africa, and here people are not getting fatter, they are getting thinner, and the reason is they are too poor to buy food. People suffer from malnutrition, they are physically deformed, they are mentally stunted. The idea of thin being attractive is a very funny one to me. I would desperately love to see more people with enough meat to cover their bones over here.

What I want is that people should be well nourished. I want that all of this malnutrition should end, it is absolutely monstrous that people grow up with a fraction of their mental and physical capabilities because of not having had the right kind of food, and enough of it, while they were growing up. And in 'rich' countries people are still poorly nourished because junk and supermarket foods don't contain enough of the most important kinds of nutrients.

Nutrition is fantastically important. You only need to see some of the horrifying afflictions that result from really bad malnutrition to realise this. You don't eat to look a certain way - you eat so that you can live! Everything you eat goes to every part of your body, including your brain. It forms the bits of your body and also delivers the energy needed to move those bits around. In other words, you, and your life, are merely the outcomes of the food you eat. A high-quality diet translates into a high-quality life. You don't do it for anybody else. You do it for yourself. You shouldn't care a fig whether people find you more or less attractive the one way or the other! What is at stake is your life, your future, every second of every day, and the things that you will be able or unable to do. That's what nutrition is about. It's not about image.