09/06/2015 07:36 BST | Updated 08/06/2016 06:59 BST

The Truth About Being "Naturally Slim" After 40

When you see someone who seems to eat a lot and is still slim, do you curse your bad luck?

Do you wish you had their genes? Or their fast metabolism?

Although genes do impact body shape and some aspects of weight, when a woman over 40 is able to "eat what they want" and still stay slim, it's most heavily influenced by behaviour.

Which is great news, because that's one thing you can copy and make your own.

But what you need to remember is that if you ask a naturally slim woman how she does it, usually all you get is nonsense about a quick metabolism and how "I got it from my mother".

In actuality, most of the time they can't tell you because the behaviours are second nature and so they don't think about them.

So instead of asking them, let me show you what they are really doing:

1. Don't surround yourself with food

One of my clients once described her desk at work as a "smorgasbord".

She was surrounded by food, and so even if she wasn't hungry, the mere sight of it, prompted her to eat what was there.

When food is in front of you, you will find it very hard to resist. So don't keep it in front of you!

Clear your environment of these types of foods. Make it so that if you want a treat, you have to go out and get it, rather than just reach over to your desk.

2. Don't waste calories on mediocre food.

Make sure that if you're eating something, that it is tasty and worthwhile.

Most people don't do this. They might be offered a biscuit and eat the whole thing even if it didn't taste very good.

If you like biscuits, only eat the best tasting ones. Don't "waste" calories on mediocre food.

3. Practice Balanced Indulgence

This is a very common behaviour of naturally slim people. If they know that they are going to have a particularly indulgent meal that night, they will eat less during the day. I call this balanced indulgence.

If you've just had an especially large lunch, don't you think you could get by with a lighter dinner?

Of course you could. But research shows that most overweight people don't think like that and eat the same amount as usual.

This is why some slim people look like they defy the laws of thermodynamics. They look like they eat a lot, but are still slim. This isn't some magic trick. It's just that they eat less at other times.

4. Share readily.

A good example of this, is sharing desserts with someone else.

Most of my clients tell me that after a while, it's hard to justify eating a whole dessert. It's too much at the end of the meal.

It's so much better to share with someone else, so you get a taste, but don't get the overwhelmed feeling of having eaten too much.

5. Eat slowly

Instead of scarfing down food as quickly as possible, take time to eat. Make meals an occasion and ensure that you enjoy and savour them as much as possible.

Contrast this with the average person who may eat some meals while standing up or driving.

6. Don't get depressed if your weight fluctuates

Even when you've been maintaining your weight all your life, you will have fluctuations. You might over-eat after a weekend away, and your weight might go up a pound or two.

When your weight does go up a little, don't beat yourself up about it. It's normal.

7. Know what to do if your weight fluctuates

If you want to maintain your weight for the long-term, you need to know what to do if your weight fluctuates upwards.

For one, you want to know what went wrong, learn from the mistake and try and prevent it happening again.

And secondly, you want to be able to bounce back as soon as possible.

Bouncing back doesn't mean going for extreme measures like crash dieting to offset the bad weekend. Instead it just means getting back to your normal routine.

You can do it too!

If you change your eating behaviour to replicate those that seem to be able to maintain their weight naturally, you can achieve what they have. These seven tips are your starting point.

For more about a behavioural approach to weight loss click here.

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