Undoubtedly there are some people who enjoy eating lettuce in the same way that others drool over bacon, crave chocolate or relish a good cheese platter.

But I'm not one of them. I couldn't bear those school meals of what was optimistically called "salad" - a plate of pickled beetroot, eggs boiled to within an inch of their lives and leaves of dull, insipid lettuce.

As an adult, my heart sinks when a perfectly decently pub meal of scampi and chips is served with a dollop of half-hearted greenery.

Most lettuce - not the leaves styled and photographed in the pages of glamorous food magazines - has almost no flavour, hardly any texture, little nutritional value and is about as exciting as a wet weekend.

Advertisement

And while lettuce might be low in fat, sugar and salt - and useful for bulking out sandwiches - the same could equally be said for cardboard.

I used to think I was alone in my disdain for lettuce. But a leading American food writer has triggered a global food debate by pointing out its futility. Tamar Haspel argues that the nutritional value of lettuce is so small - and its cost to the environment so big - that we should stop thinking of it as a wholesome staple foodstuff and instead regard it as a waste of space and resources.

Lettuce, she claims, takes up valuable space in farms and greenhouses that could be used for something more nutritious.

So is she right? Is lettuce little more than a waste of space?

Its nutritional benefits are certainly tiny. That's because a typical iceberg or cos is made up almost entirely of water.

Most vegetables are water, of course. A potato is around 80 per cent water, while a carrot is 87 per cent.

But lettuces are 96 per cent water. That's about as much as you get in a bottle of Perrier by weight (which also has minerals such as calcium chloride, magnesium chloride and potassium bicarbonate).

When you spend a couple of dollars on roughly an 800g iceberg, you're buying 768g of water - or about three quarters of a litre. It would be a lot cheaper to get it from the tap.

As Tamar Haspel damningly puts it: "Lettuce is a vehicle to transport refrigerated water from farm to table."

Advertisement

With so much water, it's not surprising that the nutritional value is so pitiful.

Icebergs are the worst offender. A large 72g serving of crunchy leaves has ten calories, 3g of fibre and 1g of protein.

It contains only 3 per cent of an adult's recommended daily intake of vitamin C, seven per cent of their vitamin A requirement, one per cent of their calcium needs and two per cent of their iron.

In contrast, rocket, spinach and watercress have far more nutrients and fibre, while a 80g serving of cooked broccoli has just 25 calories and contains 3g of fibre, 84 per cent of your recommended daily allowance of vitamin C and 24 per cent of your vitamin A, in addition to iron and calcium.

Not all lettuces are equal, however. The more colourful and flavoursome they are, the more nutritious they tend to be. Cos (or romaine) is one of the better varieties. A 40g serving offers 70 per cent of an adult's recommended vitamin A and 16 per cent of their vitamin C, along with 1 per cent of their calcium needs, and 2 per cent of their recommended iron.

According to the British Leafy Salads Association, cos lettuces are rich in potassium and also contain carotenoids, immunity-boosting nutrients.

But does lettuce just bulk out a sandwich or a salad?

Alison Clark, of the British Dietetic Association, insists that lettuce still has a place in a balanced diet. "When much of the population is overweight or obese, adding bulk to a meal or sandwich is useful," she says. "It helps with feeling full to have these low-calorie foodstuffs. In a sandwich, it means you have to chew more. Eating more slowly is helpful because it takes around 20 minutes for the stomach to send a signal to the brain to say: 'Stop eating, I'm full.'"

But dietitians are concerned about the way lettuce is sold - specifically, the high fat and calorie content of some restaurant and ready-made salads. For example, many dieters plump for a Caesar salad. Seeing it packed with leaves, they think it will help cut down their calorie intake. But often they are fooling themselves.

At the Ask Italian restaurant chain in the UK, a delicious-looking chicken Caesar salad contains a belt-busting 726 calories - nearly as much as a pizza, according to their website.

Strip away the leaves, and you'll see why. The typical Caesar salad, minus the lettuce, is a bowl full of fried bread, olive oil and chicken.

"In some chains, salads are dressed with phenomenal amounts of fat and salt which can negate the benefit of having the salad," says Alison Clark. "People are fooled into thinking it's healthy."

Home-made salads can also be deceptively fattening, too. Smother your salad with mayonnaise or dressing, and the number of calories goes up 20-fold. Two tablespoons of dressing drizzled over a plate of leaves can add up to 200 calories.

The environmental impact

There's another reason to shun lettuce and that's its impact on the environment.

Salad crops are notoriously greedy for water. That's fine in a summer like this where there's been no shortage of rain, but in drought years, and countries were water is scarce, salad-farming guzzles the stuff up.

A single head of lettuce requires around five gallons of water to grow to maturity. Add to that the fossil fuels needed to get the nutritionally poor leaves to the wholesaler, the supermarket and then to your home, and the impact on the environment emerges as even greater.

Wouldn't it be better to use precious fields, water and fuel to grow something a little more nutritious and rather more tasty?

In any case, it's not as if we actually eat all the lettuce we buy.

According to the Government's waste agency Brits throw around £270 million worth of lettuce in the bin each year - mostly because they buy it in bags which have a fridge life, once open, of only a few days.

Two years ago, Tesco reported that 68 per cent of its bagged salads are never consumed.

But bagged lettuce isn't just wasteful - it can have even less nutrition than an unbagged one. In some packets of supermarket lettuce, levels of vitamins drop after the leaves have been picked, washed in chlorine and packaged, according to food writer Joanna Blythman.

Yet despite the lacklustre taste, poor nutrition and waste, our love affair with this limp and pointless vegetable continues.

Not all lettuce is terrible, though. If home-grown, it will usually have more flavour than the mass-farmed versions. And there are ever more interesting and colourful varieties to brighten up the salad bowl.

It's time to turn over a new leaf and look for better alternatives - tastier food with more nutrients and which does less harm to the environment. Food that tastes good even when you don't smother it in oil and vinegar and mayonnaise and deep-fried croutons.

And of course, those pre-made salads are even worse

On the McDonald's website, their Crispy Chicken and Bacon Salad is promoted as a mixture of "lollo rosso, apollo, red chard, chard or spinach salad leaves served with a succulent chicken breast fillet in a crispy coating, with streaky bacon, cucumber and cherry tomatoes".

It sounds healthy enough, but is loaded with 15g of fat - or 22 per cent of an adult's recommended daily intake - and 302 calories, more than you get in a McDonald's cheeseburger, according to the nutritional values listed on their website. It also has 1.1g of salt, or a fifth of an adult's recommended intake.

A Tesco Chicken and Bacon Caesar salad has 24g of fat (more than a third of your recommended daily intake) and 442 calories - about the same as a double cheeseburger, according to their website. Without the greenery, it's a large helping of pasta, breast meat, bacon, bread, cheese and dressing.

Fat content varies hugely. Just a half pack portion of the Marks & Spencer Caesar has 13g of fat and 171 calories, while an Ask Italian Caesar has a staggering 43g of fat and 726 calories - more than three Mars bars, according to their website.

- Daily Mail