Do you often wake up in the morning feeling tired or irritable, even after a good night’s sleep? Why does this happen, and what can we do about it? Read on to discover more…


If brain fog and exhaustion sound familiar then you’re not alone – 68 per cent of Britons say they often wake feeling tired. If you sleep for up to seven or eight hours most nights but still feel unrested the next day, and are otherwise healthy, you may want to consider what’s making you feel so tired and whether you need to modify aspects of your diet or lifestyle to address the problem.

You can find out more in our health guides, including how to sleep better and how to get to sleep.

Why is sleep important?

Getting a good night’s sleep is important for a number of reasons. Firstly, it energises us through the following day; secondly, quality sleep helps us learn more effectively and process memories more accurately.

If we regularly don’t sleep well it may impact our quality of life – making us more prone to infection and illness, disrupting our blood sugar balance, increasing depression and low mood and making headaches and migraines worse. We also tend to be less motivated to participate in sports and other activities and it may influence our food choices, so we’re more likely to select sugary, refined foods rather than wholegrains, fruit and vegetables.

Tired man rubbing his eyes as he sits at his computer, cup of coffee close by

Reasons why you’re waking up tired

1. Poor quality sleep

We often associate a good night’s sleep with the number of hours we’ve slept, but that’s not the whole picture. Sleep needs to be restful and uninterrupted so that the brain can transition through each of the stages of sleep.

There are two main types of sleep: REM (rapid eye movement) and non-REM sleep. We enter non-REM sleep first, which typically involves four stages. The first stage occurs just as we doze off, the second stage is a light sleep and the third and fourth involve deep, restorative sleep. The majority of these third and fourth stages takes place during the first third of the night, making the time you go to bed an important factor for getting a good night’s slumber. These stages are especially important, because they enable the brain to process and file memories, deal with anxiety and initiate repair. Although we originally believed REM sleep, which occurs after stage four, to be the most important, research now suggests that the early stages of sleep are just as essential.

The quality of your sleep may also be affected by your environment. If it’s too warm or too bright, noisy interruptions (like a partner snoring or a baby crying) and what you’ve eaten or drunk in the hours before bed are all factors that can interrupt your ability to fall and stay asleep.

Find tips on how to improve your sleep with our guide, or try our recipes to help with sleep.

2. Sleep inertia

This temporary condition is described as ‘disorientation and a decline in mood and performance on waking’. If you experience sleep inertia you may have a slow reaction time, poorer short-term memory, impaired attention and difficulty with decision-making. However, the good news is – this is only temporary and for most people the groggy feeling lifts after 15-30 minutes.

There are several factors that may make you experience sleep inertia, these include:

  • High levels of adenosine – this brain chemical is responsible for promoting sleep and making us drowsy. Higher levels in the morning can prolong that groggy feeling but its action is blocked by caffeine which is why your morning cuppa may be a welcome pick-me-up.
  • Waking during NREM sleep – waking at this important deep sleep stage may make you more likely to experience sleep inertia the following morning.
  • Your chronotype – whether you are a natural ‘night owl’ or a ‘morning lark’ may determine how long-lasting your morning grogginess is, with night owls taking longer to get going in the morning.

You can also discover more about sleep and how much you need, or learn more about the effects of caffeine, with our health articles.

3. Irregular sleep patterns

When your sleep schedule is irregular or out of sync with your natural circadian rhythm, you are more likely to experience sleep disruption and fatigue. Sleep experts estimate 2-5% of all shift workers experience a sleep disorder that results in excessive sleepiness or disrupted sleep. Disruptions to your natural circadian rhythm not only make you more likely to wake feeling tired but you may also be more prone to infection and illness and more likely to experience disrupted blood-sugar levels and high blood pressure.

Whether your sleep disruption is due to abnormal work patterns or other reasons, you are unlikely to feel rested until you are in a position to improve the quality and routine of your sleep. You can boost the likelihood of good sleep by managing your diet and implementing lifestyle changes. Diets high in carbs combined with foods that contain the amino acid tryptophan (such as dairy, poultry and bananas) appear to be linked to better sleep outcomes.

Try our dietary tips to improve your sleep.

A hand reaches out from under the bedclothes to turn off the alarm clock

4. Sleep disorders

Some people find that they continue to wake feeling tired despite doing all they can to improve the quality of their sleep. Continued tiredness like this may suggest a sleep disorder such as sleep apnoea or insomnia, or it may be because of a physical action such as grinding your teeth or restless legs syndrome.

If this is might be relevant to you, refer to your GP or health practitioner for further advice.

5. Anxiety

Feeling anxious is the most common mental health problem worldwide and studies suggest that roughly 50 per cent of people with anxiety get insufficient sleep which can further exacerbate their condition.

Those with anxiety conditions may find falling asleep difficult and as a result tend to wake feeling tired, with their fatigue continuing through the day. If you feel overly anxious, suffer from insomnia or both then talk with your GP.

Browse our stress-relief tips and find out how diet can help.

Woman yawning, holding a cup of coffee

When might my tiredness suggest something else?

It is important to remember that extended periods of tiredness are not normal and may severely impact your quality of life. If you have taken steps to address the most likely causes, and your tiredness continues for two weeks or more, make an appointment to see your GP. They may suggest you are assessed for iron deficiency anaemia, an underactive thyroid or sleep apnoea. Alternatively, your tiredness may be a result of a psychological issue such as depression, anxiety or a bereavement.

Found this useful? Now read:

Why am I always tired?
How to eat for more energy
What is the Energy Plan?
How to eat to feel more energetic
The best sleep trackers reviewed

Do you wake feeling tired? What helps you energise your day? Share your experiences in the comments below.

Kerry Torrens is a qualified Nutritionist (MBANT) with a post graduate diploma in Personalised Nutrition & Nutritional Therapy. She is a member of the British Association for Nutrition and Lifestyle Medicine (BANT) and a member of the Guild of Food Writers. Over the last 15 years she has been a contributing author to a number of nutritional and cookery publications including BBC Good Food.


All health content on is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or any other health care professional. If you have any concerns about your general health, you should contact your local health care provider. See our website terms and conditions for more information.

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