“Housewives! Please finish travelling by 4 o’clock and leave the buses, trams and trains free for war workers,” read a poster during the second world war. Woe betide the selfish housewife who frivolously lingered on a tram past 4.15 — what looks of disapproval she must have garnered, what tut-tutting. During the war, Britain’s women were also nagged to leave the “squander bug” at home when they went shopping, to make wedding dresses out of parachute silk and told “Never use more than five inches of water in a weekly bath” (barely enough for a modern woman to rinse her Eve Lom face cloth).

The effect of all this nagging, argues ­Patricia Nicol in her charming and perceptive romp through the ration books, was that wartime Britons were far greener and more ethical than their modern counterparts. We may talk the talk (rabbiting on about carbon footprints, plastic bags and local food) but they really walked the walk. We flirt with pak choi seeds as a new credit-crunch fashion; they dug for victory. We congratulate ourselves if we remember not to leave the plasma screen on stand-by; they read by dim lights and cooked porridge in a fuel-saving hay box. “The grandparents at whom we may once have scoffed for hanging on to leftovers and hoarding pieces of string…were, in contrast to us, model global citizens.”

Much of the book’s fun is in the deft way Nicol weaves together examples of can-do thrifty propaganda. She has trawled the Imperial War Museum and the National Archives and come up with some gems. Some of the details are pleasingly nostalgic — dried eggs and spam, the wishful promotion of carrots as a daringly sweet treat (“carrot flan…reminds you of apricot flan — but has a deliciousness all of its own”) and the obsession with potato skins. In the words of one Ministry of Food advert: “Those that have the will to win/Cook potatoes in their skin/Knowing that the sight of peelings/deeply hurt Lord Woolton’s feelings.”

Woolton was the minister of food. The current government is not averse to food campaigns (the latest is the £75m Change4 Life addressing obesity), but can you imagine health minister Alan Johnson or Alistair Darling putting out an advertisement warning us that their feelings are hurt every time we binge on junk food?

Nicol shows that during 1939-45 Britain was an alien universe in many ways. Onions became so scarce that they were considered a luxurious gift “for a house-warming or even a wedding”. Individuals were expected to tailor their desires to the needs of the greater good. “Do you mind a child being sick in the back of your car?” asked the Women’s Voluntary Service when signing people up as drivers. No sane human being could fail to mind, but clearly, the correct answer was “No”. There was something a little Stalinist in all this; indeed, Nicol includes a poster of a woman in a headscarf urging “Cover Your Hair for Safety — Your Russian Sister Does!”.

Each chapter ends with ideas for incorporating wartime thrift into our modern lives. Most of these are good sense: make do and mend instead of buying unnecessary new clothes, take your own bags when you shop, ask yourself, “Is your journey really necessary?” before leaping on a plane. It is apparent that Nicol, whose words exude practical optimism, would have made a good Land Girl. She took her honeymoon in Cornwall in November, does not throw away food and makes thrifty use of an organic veg box.

It is not clear, however, how such values could be reinstalled in the nation. She shows that austerity worked to the extent that it did (and, of course, rules were flouted) only through a powerful combination of social norms and extensive government intervention. It was shame and fear of the consequences that kept people on the straight and narrow. Shame has largely vanished from Britain now — a good thing, too, if you think of changing attitudes to homosexuality, for example, or our willingness to embrace the pleasures of the table. At the heart of Nicol’s enjoyable book is a profound question: how can wartime attitudes to waste be emulated when there is no war on? Waste and selfishness have become second nature. To change this would take a vast shift in social mores, including the re-emergence of a sense of public shame, something we have learnt to live happily without as we luxuriate unthinkingly in our palatial daily baths.

Sucking Eggs by Patricia Nicol
Chatto £12.99 pp288

Times Recommends

• Superfreakonomics by Steven D Levitt and Stephen J Dubner
• The Times picks the 50 best paperbacks of 2009
• Vincent van Gogh’s letters show the soul of the artist