Water should always be your first choice when it comes to keeping hydrated. Not all liquids provide hydration and many are high in calories and sugar, so it’s important to consider what you drink as well as how much.

Water is critical to mental and physical performance. Always carry a water bottle with you and keep one at your desk to remind you to hydrate.

Remember that the symptoms of dehydration – feeling weak, dizzy and having low energy – closely mimic those of being hungry. This can trick you into thinking you need food to boost your energy levels, causing you to overeat. The best way to identify whether you’re really hungry is to drink a glass of water when you get your first hunger pangs. If you’re still hungry after 15 minutes, eat.

Contaminated or unfamiliar drinking water is one of the leading sources causes of illness for people travelling overseas. The best way to protect yourself is to avoid local tap water and drink bottled water instead. Bottled water is generally safe, but only in sealed, tamper-proof containers.

You should also bear in mind that it is not only the water you drink that could make you poorly – for example, the water you use to brush your teeth, or to wash your contact lenses or dentures could also cause a problem.

Freezing water doesn’t kill bacteria, so ice cubes in drinks should also be avoided. Finally, try to avoid food that may have been rinsed in contaminated water, such as salad or fresh fruit.