Natural yogurt.

Are you drinking enough?

Bottles of mineral water are now so ubiquitous that health-conscious people cannot make even a short journey without one. Yet the warnings about maintaining fluid levels are "not only nonsense, but thoroughly debunked nonsense", Margaret McCartney, a general practitioner in Glasgow, said.

Official advice issued by the NHS says that people should "try to drink about six to eight glasses of water (or other fluids) a day to prevent dehydration". Many schools also require pupils to bring a water bottle to school. But Dr McCartney said there is no high-quality evidence to support these claims, which are repeated by bottled-water companies to boost their sales.

The idea that we are all short of water is thought to derive from a 1945 recommendation that adults should consume 2.5l of water daily, 1ml for every calorie consumed, though this advice has only caught on in the last decade. But the crucial part of the recommendation is usually ignored – that "most of this quantity is contained in prepared foods".

Hydration for Health, an initiative aimed at medics to promote the drinking of water, which was created and is sponsored by Danone, the French maker of Evian, Volvic and Badoit bottled waters, says "many people, including children, are not drinking enough". It recommends "1.5 to 2 litres of water daily is the simplest and healthiest hydration advice you can give".

...Well, I think that Dr Margaret McCartney has a point here. People forget how much water they take in by the food they eat. Any campaign run by manufacturers of bottled water should be viewed with suspicion. It does seem daft the number of people you spot carrying bottles of water with them as though they are going for a trek in the jungle rather than to sit in an office. What is this some silly new fashion code? Transport workers must wear high visibility waist coats and office workers must carry bottled water - all in the name of safety or is someone having a joke? Whenever I see someone carrying a bottle of water, I always wonder, how far are they going? This seems as silly as people taking vitamin pills. Just eat your food and get on with your life. Stop being such a sissy, there is no need for this bottled water carrying. And those people who sip, sip, sip their bottled water, taking about 2 hours to drink 500ml - drink like an adult not a sparrow! You are only using your bottled water as a fashion accessory and we have spotted your over-priced bottle of water already, so stop this childish posing.