It is a natural feeling to feel sleepy after a long day at work, or following some strenuous exercise - and a good night's rest can be just the ticket to solve this.
However, over-tiredness could be a sign of many other health-related issues, especially if you are getting plenty of sleep but still feeling fatigued, reports the Express.
So, when does feeling sleepy signal something more serious?
There are several reasons why people may not be feeling as well rested as they expected - and some of these could require attention from a medical professional.
Doctor Raja Mohan, from Rainbow Labs, has explained some of the medical causes for fatigue, especially those that go beyond not getting enough shut-eye.
The NHS recommends that an adult gets between seven to nine hours of sleep a night to feel energised enough to take on the next day.
Read on below to discover the six medical reasons why you may be feeling tired on a regular basis.
Sleep apnoea
Doctor Mohan explained the breathing condition sleep apnoea, saying: "This condition causes you to stop breathing momentarily during sleep, leading to poor sleep quality and daytime fatigue."
Signs of the condition include:
- Breathing that stops and starts
- Making gasping, snorting or choking noises
- Waking up a lot
- Loud snoring
People may also experience bad headaches and mood swings throughout the day as a result of not getting enough sleep.
Anaemia
There are a number of potential causes for anaemia, including an iron or vitamin B12 deficiency, as well as not having enough red blood cells.
The expert noted: "Anaemia is a condition where your body doesn’t have enough red blood cells, which can cause fatigue and weakness."
Your local doctor can help by giving you a blood test and exploring options for treatment.
Depression
Another common reason for fatigue is feeling mentally unwell, as depression can cause low energy levels and lack of motivation.
Dr Mohan said: "Depression can cause a variety of physical symptoms, including fatigue and low energy levels."
Thyroid issues
Issues with your thyroid can cause low energy levels and fatigue problems, according to Doctor Mohan.
He said: "Both an overactive and underactive thyroid can cause fatigue and other symptoms."
Symptoms of an under or overactive thyroid include:
- Being sensitive to cold or heat
- Weight gain or loss
- Depression and mood swings
- Muscle aches and weakness
- Infrequent periods
Chronic fatigue syndrome
This condition is a complex problem, which is when sleep doesn't help someone recover from fatigue.
Doctor Mohan said: "his is a complex disorder characterised by extreme fatigue that isn't relieved by rest."
Diabetes
Diabetes is when a persons blood sugar levels become too high, and their body cannot produce insulin to help regulate their blood sugar levels.
Dr Mohan added: "High blood sugar levels can cause fatigue, as well as other symptoms such as increased thirst and frequent urination."
Signs of diabetes also include:
- Weight loss and loss of muscle bulk
- Itching around the penis or vagina, or frequent episodes of thrush
- Blurred vision
However, feeling tired can also be a contributing factor of a number of lifestyle choices, including dehydration and a poor diet.
Dr Mohan said: "Eating a diet that is high in sugar, processed foods, and unhealthy fats can leave you feeling tired and sluggish."
He added that what we do to our bodies and what we consume in fluids can be influential, saying: "Not drinking enough fluids can lead to dehydration, which can cause fatigue and other symptoms."
And one last reason that you may be feeling tired all the time is as simple as they come - a lack of quality sleep could be the issue.
The NHS website has issued some advice to people who feel "tired all the time", writing: "Before you see a GP, you may want to work out how you became tired in the first place.
"It can be helpful to think about:
- Parts of your life, such as work and family, that might be particularly tiring
- Any events that may have triggered your tiredness, such as bereavement or a relationship break-up
- How your lifestyle may be making you tired.
A doctor will look into the following causes of fatigue:
- Psychological causes
- Physical causes
- Lifestyle causes."
It is extremely important to speak to your GP if you need support or an explanation on some fatigue issues you are dealing with.
As NHS guidance recognises, such experiences "can affect your ability to get on and enjoy your life."
It adds: "Tiredness or exhaustion that goes on for a long time is not normal." As such, "unexplained tiredness is one of the most common reasons for people to see their GP."
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