One thing that Margaret Thatcher will always be remembered for – apart from creating the Poll Tax – is her ability to survive on only four hours’ sleep a night.

The Iron Lady’s philosophy – that “sleep is for wimps” – pretty much sums up how many people think about sleep today.

We want to work more, do more and experience more; and there simply aren’t enough hours in the day to fit it all in.

Many of us see eight hours of lying on a mattress as wasted time, but be advised: this approach to life is dangerous.

To deny yourself shut-eye is to deny yourself vitality, health and – possibly – happiness.

And, if nothing else, being sleep deprived will make you a grumpy old so-and-so.

Sleep is good. Don’t listen to those workaholics; sleep is not a lazy indulgence.

You should savour your napping time, because time asleep is time very well spent. People who have good sleep habits tend to be calmer, more emotionally stable and happier about life.

And get this: People who get plenty of sleep also have a trimmer physique. (Who’d have thought that sleep could be the “lazy man’s diet”?) You might not read it in the diet books, but getting your fill of slumber will mean your body can handle blood sugar levels better, with the result that you are less likely to crave chocolate fudge cake in the evening.

We still don’t know all the reasons why we need to sleep. The most recent research shows that sleep gives brain cells the time they need to recover by “taking out the trash”; cleaning out harmful chemicals that have accumulated during the day’s thinking.

It will come as no surprise, then, to learn that sufficient Zs gives you a sharper mind, a better memory and more patience.

So kick back this evening and turn on the chillout music playlist. Don’t worry about getting exactly eight hours; some people need more sleep, others less. Between seven and nine hours is about right for most.

And as you peacefully glide into Neverland, be glad in the knowledge that life is so much better because of it.

It’s most definitely time to open our eyes to the value of shutting them.

* Sleep difficulties are a common problem. For good advice, see the NHS Choices website (search: “NHS better sleep”). Anyone who has persistent daytime tiredness should consult a healthcare professional.