I have been on a slimming diet and managed to lose some weight. How can I keep the weight off now?

Thirst of all remember why you lost it - you have lowered your blood pressure and reduced the strain on your heart. So praise yourself. You will feel better and that alone will give you the incentive you need to keep slim and fit. Here are some more tips.

• Maintain regular exercise, walking briskly, cycling, swimming (see Chapter 10).

• Keep eating sensibly: plan your meals and follow the plan carefully.

• Eat more starchy foods (such as an extra slice or two of bread a day) to prevent you losing more weight if you have reached your target. Do not be tempted to turn to biscuits and cakes again!

• At parties or business lunches, if there is a buffet, choose carefully and don't overeat just because its free and the size of the spread is tempting (see question below on eating out).

• If hunger strikes, drink a glass of water and eat fruit - don't open the fridge door.

If you start gaining weight, look carefully at what you are eating and how much you exercise - what have you changed? If you lose weight below your target, gradually increase your calorie intake first of all by 200 kcal a day (an apple is 60 kcal, a slice of bread 80 kcal: there are many 'calorie counting' booklets on the market, listing various foods both raw and packaged); after a week, check it again and keep exercising.

I have seen two different charts for an ideal weight. What should my target weight be?

Your ideal weight must take into account your height (see Figure 9.1). Doctors work to your Body Mass Index or BMI. This is your weight in kilograms divided by the square of your height in metres:

A normal BMI is 20-25. It works well for people over 1.6 m (5 ft 3 in) up to 1.87 m (6 ft 2 in) but not so well for short or tall people. Ask your doctor or practice nurse to help you work out your BMI and set your own target BMI. Now check it against your bathroom scales which are not as accurate but which will still show any changes. You can work out what you weigh in kilograms which is equally a guide to your BMI. For example, say that your BMI is 27 and that you want to get to 25, work out your kg at each BMI point and then, using your bathroom scales, all you need to do is set your kg target, as you know what BMI it represents. If you are not sure what to do or how to do it, ask the practice nurse to help you. Here is an example to help you:

A 1.87m (6 ft 2 in) man weighs 95 kg. His calculated BMI is:

He would like to be healthier with a BMI of 24-25 so the calculation is:

He now knows what to aim for on his scales.

Check your weight once a week only and aim to lose 1 kg (2.2 lb) in the first week and then 0.5 kg a week thereafter. If you use bathroom scales, do not put them on a carpet, and check them against a known weight (such as bags of flour) from time to time. Compare them with your doctor's scales or a large one in a chemist's shop.

Figure 9.1 What you should weigh. Take a straight line up from your height (without shoes) and across your weight (without clothes), and put a mark where the lines meet. How did you do?

I find the whole business of BMI confusing - can it be made simpler?

Of course. Simply follow the height and weight chart. Another simple formula is:

• Height in cm minus 110 = optimal weight in kg for men

• Height in cm minus 100 = optimal weight in kg for women.

So, if you are male measuring 5 ft 10 in, convert your height to centimetres (177.8 cm), take away 110 and you reach 67.8 kg. This is your ideal weight.

I have heard the nurse talk about a waist/hip ratio. What is this? Does it apply to my husband as well as me?

If your tummy is fat, the risk of heart problems increases and you can calculate the risk by comparing the waist measurement with that at the hip. You divide your waist measurement by your hip measurement. So, if your waist measures 26 in and hip 34 in, then you would have a ratio of 0.76 (26 divided by 34); you would not be at risk because the safe ratio for women should be no more than 0.8; this means that your waist should not be more than 80% of your hip measurement. Put another way, being apple-shaped is bad but pear-shaped is positively good!

The ratio for your husband, say with a 40 in waist and a 34 in hip, is calculated by dividing 40 by 34 which equals 1.18. He would be at risk because the safe ratio for men should be no more than 1.0. So his waist should not be greater than his hip measurement or the ratio would be over 1.0. Having a belly that's bigger than your hips increases your risks of getting coronary artery disease.

Waist circumference is used more as a sign of obesity and predisposition to diabetes. It is measured breathing out, 2 cm (1 in) above the umbilicus (navel). For men, if your waist is 94-102cm (3 7-40in) you are overweight; over 102 cm (40in) and you are fat (politely known as obese). In women, if the waist is 80-88cm (32-35 in) you are overweight, and over 88 cm (35 in) you are fat.

Doctors tend to focus more on abdominal obesity which increases the risk of heart disease.