Trekking in a foreign country provides the opportunity to sample new foods and a new culture and unfortunately possible exposure to new diseases. Many diseases are water borne and ensuring safe water is a priority. Find out how to keep well when trekking abroad.

Most of the interesting and challenging treks involve travelling to some remote corners of the world. You have the opportunity to experience a new culture, new foods and new environment. However, different food and standards of hygiene can bring some new health problems too.

It is this contrast which usually disrupts your normal metabolism. So much so, that one of the first things you experience during the first few days of your trek, is a change in bowel habits. This is normal and presents itself as either diarrhoea or, the opposite extreme, constipation. The former is usually blamed on mild food poisoning. However, if you do not feel unwell, it is more likely to be due to the increased stress and excitement of the adventure that lies ahead, and the disruption in your body clock as you travel across time zones, tiredness from travelling and a change in drinking and eating habits. In this situation, avoid taking anti-diarrhoea medication (such as Imodium or Lomotil) and simply let your system adjust to the new environment.

Tips for healthy trekking

• Water is the carrier of many infections. Never drink the local water supply.
• Always wash fresh fruits and vegetables with purified or boiled water.
• Avoid adding ice to drinks, no matter how hot it gets - it is usually made from local water.
• If you drink bottled water, ensure the seal is intact. The water you buy could be tap water re-sold in a bottle.
• Ensure you have a suitable and reliable system of water purification with you throughout the trek. Iodine crystals are effective but leave an unpleasant taste. Flavoured crystals and tablets that neutralise the taste are available. Puritabs do not kill cysts that cause giardia - especially common in African countries.
• Boiling is an effective way to purify water - but has limitations at altitude. Water boils at a lower temperature at high altitudes and therefore does not kill all bacteria and viruses and their spores.
• Water filters are effective, but expensive. Choose a pump action design rather than a drip filter into a single cup. The latter takes at least five minutes to filter one small cup of water!
• Do not share your water bottle with others - except in an emergency.

Some trekking companies, such as Sherpa (run by Doug Scott) actively train their teams of local porters in basic hygiene principles for preparing and serving food.