Why Nando's chicken isn't wholesome as you think: Celebrities love it. To the middle classes, it's guilt-free fast food. If only they knew the full story... Despite the recent hot weather, Lee James is rarely tempted to open the windows of his detached home. It's not that he doesn't like the great outdoors - more that the 37-year-old plumber doesn't want the smell of it to come indoors. "At its worst, the smell is like stagnant, putrid meat," explains Mr James. It's so bad that if it comes over, you can't go outside. Popular: Nando's meals, such as the chicken fillet pitta, have helped the chain expand rapidly in Britain The odour emanates, says Mr James, from a sprawling factory a stone's throw from his property in Brackley, Northamptonshire. It is the headquarters of a company called Faccenda, one of the biggest chicken processors in the country. Every week it handles two million chickens. These birds will have been bred in hangar-like sheds, never setting foot outdoors in the six weeks it takes them to reach their genetically engineered slaughter weight. Cheap chicken, in other words - with the odorous fall-out from which Mr James and his neighbours can never escape. Asda and KFC are among Faccenda's many customers. But the meat it produces also ends up at Nando's, the go-to destination for a new generation of health-conscious, middle-class Britons looking for a guilt-free alternative to deep-fried fare. In the past two decades, the chicken chain has spread across the country. It has 288 outlets and aims to hit the 400 mark in the next few years. Each week it serves up more than half a million chickens to 800,000 customers, presenting itself as a cut above the takeaway chains. It plays up its popularity with celebrities, happy to spend their time tweeting their love for its food (and failing to mention, of course, they will often eat there for free). Unpleasant neighbour: Lee James who lives near to the Faccenda chicken factory says it smells of 'stagnant, putrid meat' At the heart of the Nando's menu is - you guessed it - chicken, marinated in a spicy sauce and cooked on a flaming grill. From a whole bird to wings or a breast fillet, the chicken is served in a wrap or pitta bread, or as a burger, with side dishes. Half a chicken with chips and coleslaw - one of the most popular choices - costs £9.95. Nando's makes great play of the quality of the meat it serves: all from the UK and all fresh, not frozen. "All Nando's chicken is Red Tractor assured," says the menu, referring to a farming scheme supposed to ensure that livestock is kept in well-ventilated accommodation with constant access to food and water. Nando's has become the go-to destination for a new generation of health-conscious, middle-class Britons The menu says Nando's chicken has "met high standards of food safety, animal welfare and environmental protection, here in the UK. This means our chicken is not only tasty, but also happy and healthy. But Philip Lymbery, chief executive of Compassion In World Farming, says: "These are chickens that are reared in their tens of thousands, in very high stocking densities and pushed to grow very, very fast only to be slaughtered at unnaturally young ages," he says. That can often cause the animals to suffer cardio-vascular diseases. They can then become painfully crippled because they are growing so fast that their lungs, their bones and their heart cannot keep up. Such an image is a million miles away from that which Nando's would want. Despite spending only a fraction of the advertising budget of KFC and Burger King, it is rarely out of the headlines. In the past few weeks those pictured in their local branch included the heiress Tamara Ecclestone, One Direction's Harry Styles and singer Beyoncé. Celebrities lower down the food chain - footballers, reality television stars and X Factor contestants - are also regulars. Their visits rarely pass without them commenting on Twitter. "Nandos is one of those amazing gifts given to us from the man above GOD!!" is one of many such comments posted by Mark Wright, star of The Only Way Is Essex, to his two million followers. Wright is said to have a Nando's "black card." Singer Ed Sheeran was pictured flashing his. This is selectively distributed and gives the holder right to free food from the chain. The association with this type of celebrity is reflected in the chain's customer base. A typical branch will have tables filled mainly with diners aged from their mid-teens to their late 20s. It is popular with young black Britons and with other ethnic minorities (some 60 of the chain's branches serve only Halal chicken). Nando's is famous for its "peri-peri" sauce, a version of the piri-piri marinade used on chicken in Portuguese restaurants worldwide. Nando's origins, however, are South African. Tulisa Contstavlos, left, is one of many celebs to have posted a picture of herself at Nando's Tamara Ecclestone with new husband Jay were pictured arriving at a Nando's restaurant in London recently In 1987, entrepreneur Robert Brozin and his friend Fernando Duarte popped into Chickenland, a Portuguese takeaway in Johannesburg. They thought the chicken was the best they had ever tasted and bought the restaurant for £25,000, renaming it Nando's, after Fernando, a Portuguese national. They then launched it as a chain and it now has close to 1,000 outlets in 30 countries. Nando's UK is part of an international, privately run business parented by a company called Yellowwoods. It is owned by a South African family, the Enthovens, who made their fortune in insurance, and were early investors in South Africa. They opened the first two British branches in London in 1992 and within ten years had 29 outlets. But in the past decade, expansion has been rapid. In 2012 Nando's registered a profit of £14.7 million, generated on sales of £419.5 million - a 26 per cent increase over the year. One key to that success has been keeping the cost of the food in line with its customer's pockets. This includes buying the type of chicken it does - not that customers would get any real understanding of that from the information supplied by Nando's. Nando's is famed for its 'peri peri' sauce - a take on the spicy marinade used in Portugese restaurants throughout the world On its website it states: "As a chicken restaurant group, we are committed to very high standards for our chickens. The quality of our core product is of the utmost importance to us and we believe that quality product and clear consciences can only be achieved if the welfare and health of the chickens are a priority for our business. On its menus it says the chickens are raised to standards set by the Red Tractor farm assurance scheme in "well-ventilated barns with constant access to food and water." Elsewhere, it adds: "We are committed to the highest standards and therefore the quality, welfare and health of our chicken is a priority." But critics argue that using chickens raised to Red Tractor standards simply does not equate to "highest standards." They say Red Tractor, Britain's most widely used food assurance label, does little more than meet minimum legal requirements. A spokesman for Red Tractor insisted that it "includes standards that are not only above EU legislation but also above UK legal standards". The RSPCA, which runs its own assurance scheme known as Freedom Foods, believes that there are numerous welfare issues associated with chickens reared in this way. These include rapid growth rates that can lead to up to one third of meat chickens being unable to walk properly. And the "barns" are huge sheds in which up to 50,000 birds will be kept. On its website, Nando's claims that it is "actively looking at RSPCA Freedom Foods and Free Range chicken." But it adds that they "also need to consider the price our customers are willing to pay." Dr Marc Cooper, a senior scientific manager with the RSPCA, says customers are becoming increasingly demanding about the sourcing of the food they eat in restaurants. "Supporting higher welfare adds value to a food business and, most importantly, it improves the lives of animals reared for meat," he says. Back to Nando's, a spokesman says that while they do adhere to Red Tractor standards, the majority of their chickens are raised in environments enriched in ways "above and beyond" that standard. As a result, we're confident that they are reared responsibly and with care, in a way that our loyal customers would expect from us. The chickens used in Nando's food have never set foot outdoors in the six weeks it takes them to reach their genetically engineered slaughter weight He added that the company had recently reviewed its supply chain but did not believe there are enough suitable chickens in the UK at a higher welfare standard to meet its demands. We're constantly monitoring the industry and should the situation change, then we would of course fully explore other viable options. Faccenda also defended its practices: "We place great emphasis on operating a sustainable, ethical agricultural supply chain and accordingly take our responsibilities for bird welfare extremely seriously. Red Tractor is a robust traceable scheme, which we fully support, delivering globally recognised standards which are above both EU legislation and UK legal requirements. We therefore fully support the comments on the Nando's website concerning the welfare of birds supplied to their restaurants. Faccenda employs almost 3,000 people and has had a significant presence in the Brackley area for over 50 years. We will continue to respond proactively to any concerns raised as part of our enduring commitment to the communities in which we operate. Given the success story that is Nando's, it seems unlikely that change will happen any time soon. Instead, the Faccenda factory and other giant poultry producers will continue working around the clock to supply the 25 million birds Nando's will get through this year. Bad news for the chickens, animal welfare campaigners will doubtless argue, and bad news for those who live downwind of the factories where their brief lives come to an end.