Us Brits are a sleep deprived nation with a whopping 70% of us not getting the recommended eight hours of sleep per night.

As a result, exhaustion has become so common that its gained its own acronym: TATT, which stands for “tired all the time”.

According to the NHS, lack of shut-eye is a major cause of TATT, but the condition should not be dismissed as a normal part of 21st century life.

If you’re struggling to sleep, it could be a sign of serious psychological stress.

Alternatively, a person may experience exhaustion when they have no apparent problems sleeping at all. In this case, TATT could be a sign of a physical underlying health condition that needs addressing.

What is the difference between tiredness and exhaustion?

Feeling a little groggy every now and then is a common symptom of tiredness, but those who report feeling tired all the time are experiencing exhaustion.

Dr Sam Rodgers, general practitioner and medical director of online health checker Medichecks, explains the difference.

“Everyone feels tired, at the end of a busy day or a long flight or marathon training. Tiredness will ease after rest and recovery and does not stop you from what you are doing,” he tells HuffPost UK.

“Exhaustion is when you are completely drained, both physically and mentally, to the extent that you cannot carry out your normal activities at work or home.”

Dr Clare Morrison, the general practitioner for online doctor service MedExpress, adds that “the main difference between tired and exhausted is simply the degree of weariness”.

“So if someone runs a couple of kilometres or puts in a seven hour study day, they’d be tired,” she tells HuffPost UK.

“On the other hand, if they ran 10 miles or worked for 24 hours, they’d be exhausted.”

Why do I feel tired all the time?

According to Dr Rodgers, a number of lifestyle factors can lead to TATT.

“There are obvious factors such as a lack of sleep, not eating well, not exercising or feeling over-stressed and trying to fit in too much,” he says.

“It’s also important not to forget our emotional and psychological health, if there is no physical cause identifiable then we would recommend talking through your symptoms with your GP.”

Dr Morrison adds that feeling tired all the time could be a symptom of a more serious underlying health issue. These can include:

:: Thyroid problems :: Diabetes :: Food intolerances :: Sleep apnoea – where the walls of the throat relax and narrow during sleep

According to Dr Morrison, consuming “too much alcohol” can also lead to TATT, so patients should forget about that “night cap” and stick within the NHS’ maximum consumption recommendations.

The NHS also suggests that being overweight or underweight can cause tiredness.

“That’s because your body has to work harder than normal to do everyday activities,” the website explains.

“If you’re underweight, you have less muscle strength, and you may feel tired more quickly.”

How can I feel more energised?

If there is no obvious reason for why you’re experiencing TATT, visit your GP. They will likely refer you for blood tests to rule out any of the medical causes of tiredness mentioned above.

However, Dr Rodgers says you may be able to reduce symptoms of TATT yourself by “assessing your lifestyle and maybe making some basic changes”.

“Most of us need seven to eight hours sleep and it’s best to avoid using your phone or watching TV an hour before you go to bed. Instead, have a warm bath and read a book to help you prepare for sleep,” he says.

“Try to exercise three times a week as a minimum and follow a balanced diet with plenty of oily fish, leafy green vegetables and fruit – eating well will also help to make you feel more energetic.”

He adds that as well as impacting your lung health, smoking can make you tired, so consider trying to quit.

“Get some fresh air – get out at lunchtime for a quick walk around the block or switch the gym to an outdoor run or park workout,” he says.

“If you have a busy lifestyle, make sure you give yourself some time off. Keep a couple of evenings and weekends free so that you can just go home and relax.”

Dr Morrison adds that ensuring you’re in bed before midnight can help you feel recharged, as can taking up relaxing hobbies such a meditation.

If tiredness persists, both GPs recommend going to visit your doctor for support, tests and further advice.