THE HUMAN CONDITION Muesli bars and fruit drinks may do wonders for your conscience, but are they better for your health? Hester Lacey takes a closer look at 'healthy' snacks
IT'S FOUR in the afternoon and time for a snack. You want chocolate and a Coca-Cola, but your conscience takes you to the health food shop for a flapjack and a can of "sparkling spring water and pure fruit juices". You would be happier with a Mars bar and a Coke but at least you're being virtuous - aren't you?

Perhaps not as virtuous as you think. Your flapjack contains more calories and fat than a Mars bar and your can of spring water and fruit juice contains more calories than a can of Coke. You've sacrificed that wonderful lift that only chocolate can give, for some rolled oats mixed with margarine and sugar.

Consumers, bombarded by warnings of the dangers of fatty foods and sweets, are turning to alternative products: yoghurt-coated peanuts and muesli bars instead of sweets and chocolates; yoghurt desserts instead of dairy ice-cream; spring water and fruit juice instead of Coke. But some of these supposedly healthy foods have been the subject of slick marketing and packaging. Often if it's a reduction in calories and fat you're after, nine times out of 10 you would do just as well with a mainstream snack.

While flapjacks and cereal bars and yogurt-coated this and that don't actually claim to be low-fat or low-calorie, their presence on the health food shop shelves and their cleverly designed wrappings make the customer assume they are better for us than their mainstream counterparts. And while most of them put the nutritional information on the back of packets, many do not.

Jack Winkler of the National Food Alliance, a coalition of consumer and health groups, says that manufacturers are taking advantage of a combination of increased consumer awareness about what is good for us, and a lax regulatory system. "In this country the general level of nutritional knowledge is high. We know nuts, vegetables, yoghurt, and spring water are good for us and therefore we assume 'healthy alternatives' made with these ingredients are better for us. Manufacturers don't even have to make claims. They highlight a few healthy sounding ingredients, give the product a natural, healthy-looking packaging and we do the rest. These are what is known as 'implied claims' and there is nothing we can do about them."

Sue Todd, senior nutrition researcher at the Consumers' Association, agrees. "It should not have to be this way but the onus is on the consumer to be better informed about what certain foods contain rather than on the manufacturer to be more honest."

So just how do health snacks and the normal nip-into-the-newsagent variety compare? All values given are calories and fat grams per 100g or per 100ml.

First, the chocolate bar and its rivals. Compare the Jordans Crunchy Bar ("crunchy cereal bar with honey and almonds"), 465 calories, 22.8g fat; the Frusli ("raisin and hazelnut chewy cereal bar for great taste and great nutrition"), 431 calories, 17.1g fat; the Tracker ("chewy oats, nuts and crisped rice bar"), 541 calories, 30.5g fat; and the Handmade Flapjack Company flapjack, 430 calories, 20.3g fat, with the Mars bar, 452 calories, 17.5g fat, and the Milky Way, 454 calories, 16.6g fat. There's little to choose between the cereal bars and the unashamed chocolate. Weight for weight the flapjacks have fewer calories. But flapjacks are generally sold in 100g bars while chocolate bars come in 60g sizes.

Surely spring water and fruit juice must be less fattening than fizzy pop? Again, there's not much in it. Look at Rio ("sparkling spring water with pure peach, mandarin, lemon and grapefruit juice"), 45 calories; Oasis ("naturally still refreshment with spring water and real fruit"), 40 calories; Purdey's ("sparkling herbal multivitamin drink"), 38.5 calories, lined up against Coke (non-diet, of course) which has 43 calories, as does Sprite. All these drinks come in 330ml cans, so a can of Coke has only 15 more calories than a can of Purdey's and 7 calories less than a can of Rio. Giving up on canned sparkle in despair? Straight orange juice contains roughly 50 calories per 100ml and cranberry juice 49.

Frozen yoghurt with the "rich smooth taste of Haagen-Dazs and the wholesome benefits of frozen yoghurt" has 140 calories and 3.5g fat - more calories, although less fat, than Loseley dairy ice-cream, which clocks up 115 calories and 5.5g fat. Another frozen yoghurt, Kemps, has only 100 calories and 2.5g of fat per 100g, so it is possible to be virtuous.

Yoghurt, though, is not an automatic indicator of integrity. There's no need to pick a yoghurt coating over a chocolate one (unless you happen to prefer yoghurt). Compare yoghurt-coated peanuts (Holland & Barrett), 541 calories, 36.7g fat; and M&Ms chocolate-coated nuts, 507 calories, 25.5g fat.

And finally, the dernier cri of smart snacking: vegetable chips. The Stamp Collection ("all natural luxury vegetable chips with sweet potatoes, carrots and beetroot") has 475 calories and 36g fat per 100g, while Walkers crisps have 550 calories and 38g fat. The "luxury chips" have less calories weight for weight - but they come in 50g bags, whereas crisps come in 30g bags. So per bag, crisps have fewer calories and less fat - and who only part-eats a bag of crisps anyway?

Of course, calories are not the be-all and end-all. Manufacturers are quick to point out that they are not doing anything wrong. Kevin Collins, brand manager for Rio, made by Hall and Woodhouse Ltd, says the firm has been very cautious about how the product is presented to consumers. "We have a high fruit-juice content and the very fact that we make a light version of Rio must indicate something about the calorie levels in the standard variety," he says.

A spokeswoman for Jordans which makes Frusli and Crunchy bars says that the difference between their products and Mars bars is the "quality of the calories". "We never put ourselves up as a slimming product," she says. "The source of calories in our bars is well balanced with calories coming from cereals, nuts and complex carbohydrates rather than toffee and chocolate."

However, in a straw poll of afternoon snackers, the unanimous verdict was: "Never mind calorie quality, give us the chocolate."