It's amazing how excess weight creeps up on you in your thirties without you becoming aware of it. Suddenly you catch sight of yourself in a shop window or you see a picture taken at your friends wedding and you can't believe how much larger you've become. How did that happen? It feels like pounds of fat appeared overnight.

The bad news is that your metabolism (the rate at which you burn calories) does drop quite naturally from your thirties onwards. So you will start to put on weight more easily. But before you get too depressed be aware that the effect is so marginal that piling on the pounds does not have to be inevitable. It's more likely that you have been getting into bad habits and eating more or moving less than you were before.

If you want to avoid the extra 10lb that the average woman gains in weight between thirty and forty take care not to fall into the following lifestyle traps.

Lifestyle Trap 1 : Too much going on

With partner, kids and/or career all taking your attention, life in your thirties suddenly becomes much more complex than it was before and the time you have for yourself seems to disappear somewhere between school runs, getting the report finished and keeping the house one step above chaos. Almost inevitably you end up taking less exercise and eating out more or using take-aways to cope with getting meals on the table. Try and give yourself and your health a higher priority by asking for help, reducing your commitments and letting less important things slide.

Lifestyle Trap 2 : Matching portions

There's a time of danger when you move in with a partner, which often takes place in your thirties. You start cooking for him and eating the same meals and often the same portion sizes. Whereas you might have made do with something on toast or soup some evenings it's now full dinners with dessert. While your man can probably take the calories - all that excess lands just where you don't want it - on your tummy and thighs. Take care to eat only what YOU need and don't try and match your partner meal for meal.

Lifestyle Trap 3 : Eating for two

For many thirty-year-olds weight problems coincide with having children. Although you need just 300 calories more a day after the first 3 months of pregnancy, it's easy to use having a baby as an excuse to eat and eat. And that excess weight can be hard to lose afterwards. Often the problem is compounded by a second pregnancy before you've lost the weight from the first. To avoid excess weight gain keep exercising as long as it's safe to do so throughout your pregnancy and continue to walk the weight off afterwards - something you can do with kids in tow! And keep eating sensibly and healthily throughout. Pregnancy is a great time to get in the habit of eating well.

Lifestyle Trap 4 : Losing Muscle

If we don't do anything about it, we start losing some strength and muscle each year from our thirties onwards. As each pound of muscle burns about 50 calories a day even when you are at rest, it's important to gain that strength back through resistance or weight training. You should also avoid any diet which advises losing more than a pound or two of weight a week. More than that and you are likely to lose muscle as well as fat. And if you end up putting weight back on, as many people do, it's all fat. This is a major reason for avoiding the yo-yo diet syndrome - you end up fatter (literally) than ever.

Lifestyle Trap 5 : Complacency

In your thirties you're unlikely to see the symptoms of the poor health choices you're making. It's probable that heart disease, diabetes and other nasties have yet to show their face but these silent killers are loitering in the background. Don't take your health for granted. You'll regret it very quickly in the years to come which will be here soon enough. Give your health a top priority and do something about your health and your weight while you still have plenty of time.

Of course you can still look great in your thirties, forties and beyond. There's no real danger in hitting the big-30 (or any other birthday for that matter). The danger always comes with a change in lifestyle. And that's something that you choose - so it's all up to you whether you want to be fat or fabulous by the time you reach 40.

Copyright 2005, Janice Elizabeth Small