The mid-morning snack trolley is being loaded up at the Royal Free hospital in north London. There are a few newspapers on the top shelf and toiletry bits and pieces on the bottom. The rest of the space is given over to sweets, biscuits and cans of fizzy drink. The total sugar load of the trolley, about to be wheeled around the wards of sick people, is considerable and, some believe, bad for the health of even those who are well.
The two elderly volunteers pushing it towards the lift say yes, people have suggested the trolley's wares are unhealthy. "But if I was ill, I'd want a bit of a treat," says one.
Sweets and colas are no longer treats, however. They are part of our daily diet, contributing to the 30kg (66lb) a year or more of sugars consumed by the average UK adult. The WHO says no more than 10% of our food energy should come from sugar, while 22-year-old UK guidelines put the proportion at 11%. We are eating more than that: most adults are on 12.3%, children aged four to 10 are on 14.6% and those aged 11 to 18 are on 15.3%. Those figures come from the government's national diet and nutrition survey, but include only added sugar - excluded are "intrinsic" sugars, such as those in fruit, fruit juice and milk.
Some of our sugar consumption is obvious -, in our fondness for confectionery, cakes and puddings, for instance. The UK tops the European league table in sales of sweets, cakes and biscuits. But much of it is hidden in what we think are entirely savoury foods.
Each medium slice of Kingsmill soft white bread contains 1.5g of sugar. A slice of apparently healthier wholemeal contains 1.7g of sugar. A supermarket-bought 250g margherita pizza made by Pizza Express contains 11.2g of sugar, or 5.6g per portion if shared between two.
Since the 1970s, sales of sugar for the table and home baking have steadily gone down. In 1974, we bought 535g of sugar per person per week. By 2007, that was down to 125g. But we have made up almost all the shortfall in sugars contained in processed foods consumed outside the home, up from 267g per person per week in 1974 to 568g in 2007.
Sweetened soft drinks are full of sugar. Both Pepsi and Coca-Cola contain 35g of sugar - nine teaspoons in a 330ml can. Pepsi Max, with no sugar, Diet Coke and Coke Zero are available for those who are worried and Coca-Cola launched a smaller 250ml can (26.5g of sugar) of standard Coke in July in response to the concerns.
Pepsi Max is PepsiCo's best seller in the UK, but original sugar-heavy Coke still outsells Coca-Cola's diet versions combined. The Coca-Cola company also sells Sprite (21.8g sugar per 330ml), Fanta (22.8g per 330ml) and Dr Pepper (34.1g per 330ml), although all have low-sugar alternatives.
Supposedly healthier sports drinks are also high in sugar - Lucozade Original in a 380ml bottle contains 33g, although the maker, GlaxoSmithKline, has pledged to cut that by 8% as part of the government's public health responsibility deal. While school vending machines can no longer contain sweet carbonated drinks, leisure centres are full of them.
Meanwhile, some sugars have slipped into our diets almost unnoticed. In the 1990s, saturated fat was blamed for obesity. Low-fat versions of dairy and other foods were launched and filled the supermarket shelves. But without the fat, many products and ready meals would lose both taste and texture. One of the answers was to add sugar.
A recent survey by Which? found that Tesco low-fat strawberry yoghurt contains 20.2g of sugar and 130 calories, compared with 16.9g and 123 calories in a standard strawberry yoghurt from Activia. McVitie's light chocolate digestives contain 2.7g of fat, compared with 4.1g in one of its standard digestives, but both have 5.1g of sugar and the calorie content of the light biscuit is 77, only nine calories less than the standard version. Philadelphia Light contains 25% more sugar than Philadelphia Original.
"Consumers are choosing 'low-fat' and 'light' options believing them to be a healthier choice but our research has found that in many cases they're not living up to their healthy image," said a Which? spokesperson. "We found many of the products we looked at had a similar calorie content to the supposedly less healthy option and also contained more sugar. Our advice to consumers is to read the nutritional labels carefully."
Horrified by the snack trolley and the sweet-laden shelves of the WH Smith outlet in the hospital reception that supply it, a Royal Free cardiology specialist registrar, Dr Aseem Malhotra, started a campaign for a ban on the sake of junk food in hospitals. It got the backing of the British Medical Association in January. "Hospitals have become a branding opportunity for junk food," he says. "I'm not aware of any hospital that doesn't do it. It is perverse when we are telling people about healthy diets. Added sugar has no nutritional benefits."
In Picture: A pile of sweets. Photograph: Dominic Favre/EPA