Primary sources

John Crace rounds-up research news from around the globe, this week: the chimpanzees that have developed their own tool kits

In pursuit of the greatest happiness

Tim Worstall: GDP is not the be-all and end-all of our existence; it talks of value added to economies but has little to say about anything else

Raw shellfish likely cause of Heston Blumenthal’s Fat Duck poisoning

Health Protection Agency report blames norovirus for making 500 diners ill at world-famous restaurant

Children risk cancer by eating salami and ham, warns charity

Bad habits 'could lead to bowel disease in later life' says World Cancer Research Fund

Organic food: the natural choice

Leo Hickman: Why the mock outrage over the nutritional value of organic food? There are a host of more compelling reasons to eat it

Documentary on intensive pig farming faces legal threat

World's largest pork processor Smithfield Foods hits back at criticisms in Pig Business

Ghent goes vegetarian

If somewhere in the UK were to go vegetarian for one day a week, where would it be?

Day of the lentil burghers: Ghent goes veggie to lose weight and save planet

Belgian council claims to be first town in Europe not to eat meat for a day every week

Weighing up the costs of being obese

Obesity is becoming analogous to the smoking debate. So will future carbon taxes place a burden on the overweight, asks Leo Hickman