5 surprising signs you’re dehydrated

From passing urine to keeping your joints moving well, your body uses a lot of water to perform basic functions that keep you healthy. Feeling thirsty is a sign that your body’s telling you to drink more, but it’s not the only way your body subtly lets you know you’re in need of a top-up.  Jake Williams, Lifestyle Health Adviser for Bupa Health Clinics, shares five signs that you’re dehydrated.

1. Struggling to snap out of a bad mood

There are lots of reasons you could be in a bad mood, but if you can’t work out what is making you feel grumpy, go and get yourself a glass of water. Studies have shown that hydration levels can have a direct impact on how you rate your own mood. Try monitoring your water intake over a few weeks alongside tracking your mood, you might be surprised to find that there is a direct correlation between the two.

2. Feeling sleepy

Did you know that dehydration can make you feel sleepy, even if you’ve had your full eight hours? Around 75% of your brain is made up of water; your body uses water reserves throughout the day and if you don’t replenish those levels, you might be left feeling lethargic.

3. Itchy eyes and dry mouth

Your mouth and eyes give away a few signs about your hydration levels. If your eyes feel itchy, your mouth feels sticky or your lips are cracking, consider incorporating some more hydration into your diet.

4. Dark coloured urine

Depending on how hydrated you are, the colour of your urine can vary from dark yellow to a very light yellow – if it’s any colour other than a very light yellow, you could do with drinking more! Of course, there are other factors that might influence the colour of your urine, but it is a good initial indicator of your hydration levels. 

5. Constant dull headache 

Water plays a vital role in giving your brain the nutrients it needs to fully-function, so if you have a headache, or you’re having trouble concentrating, it could be a sign that you’ve not drunk enough water.

How to reach a good level of hydration

As a rule, make sure you’re drinking little and often to maintain good hydration levels – you need between one and a half to two litres of fluid every day; the equivalent of around 10 glasses. You can feel dehydrated as a result of being unwell and you can become unwell because you’re dehydrated. Either way, it’s important to make sure you replenish the salts and sugars that your body is lacking – water alone can’t always provide everything you need – instead, you could try adding a rehydration sachet to your drink. If you’re dehydrated due to being unwell – through vomiting or diarrhoea – your body loses more water than it does usually. Though the thought of drinking may make you feel unwell, it’s important to continue to drink water when you can to make sure that you’ve got enough in your system. In more severe cases, you’ll need to seek urgent advice from your GP or a pharmacist. Think about what exactly you’re drinking: avoid excessive amounts of caffeine and alcohol as these can actually dehydrate you. The healthiest drink is water, but you can occasionally mix things up with coconut water, fruit juice, squash, fizzy drinks, smoothies or milk– though remember that these drinks all include additional sugars, so be sure to drink them in moderation.

Remember that thirst can often be mistaken as hunger signals which often overshadow the signals for thirst, which can be weaker

Studies have shown that 37% of people confuse hunger and thirst signals. So if you find yourself feeling hungry, it can be useful to first have a drink to see whether it suppresses your appetite. Lastly, you can top up your hydration levels with sensible food choices, too! Foods with high water content – including cucumber, lettuce, watermelon, grapefruit and strawberries – all help to reach the right hydration levels. If you struggle with getting adequate fluids, consulting a nutrition professional can help you get creative with liquids and up your intake. Alternatively, if you think your constant struggle with thirst is something else that might need medical investigation, it’s always best to consult your GP who can run further tests.