So why do some people seem to need less sleep than others?

It’s a question that has fascinated scientists for years. Here’s what we know.

Natural short sleepers

Scientists call this the natural short sleep phenotype — a biological trait that allows people to get all the benefits of sleep in less time.

We’re still learning about how common these genetic mutations are and why they occur.

Not everyone who sleeps less is a natural short sleeper

Often, their short sleep is due to long work hours, social commitments, or a belief sleeping less is a sign of strength or productivity.

For the average person, it’s not sustainable to only get a few hours sleep a night. Source: Getty / Carol Yepes

In today’s hustle culture, it’s common to hear people boast about getting by on only a few hours of sleep.

For example, short sleep has been linked to an increased risk of obesity, diabetes, high blood pressure and cardiovascular disease (heart disease and stroke).

The weekend catch-up dilemma

A recent large study suggested weekend catch-up sleep may not offset the cardiovascular risks associated with chronic short sleep.

That said, maintaining such regularity can be particularly challenging for people with non-traditional schedules, such as shift workers.

So, was Thatcher a true natural short sleeper?

It’s hard to say. Some reports suggest she napped during the day in the back of a car between meetings. That could mean she was simply sleep-deprived and compensating for an accumulated sleep debt when she could.