Quitting smoking and taking a daily walk can do more than just protect your heart: they also help protect from developing rheumatoid arthritis. They are two of 10 steps someone at risk can take to delay or prevent the onset of the often debilitating autoimmune disease. University of Queensland PhD candidate Louise Koller-Smith has created a simple guide for clinicians to use to target those at higher risk of rheumatoid arthritis but without the clinical disease. "What most people don't know is that there are some lifestyle changes you can make to reduce your risk of developing rheumatoid arthritis," Ms Koller-Smith said. "In fact, new evidence shows that about 40 per cent of cases of rheumatoid arthritis are caused by lifestyle risk factors, which are things that you can change." Rheumatoid arthritis is the most common autoimmune disease in the world, affecting 23 million people, with more than half of them of working age. Unlike the wear-and-tear damage of osteoarthritis, rheumatoid arthritis occurs when a person's immune system mistakenly attacks tissues in the lung, gut and lining of joints, resulting in inflammation and damage that can eventually lead to chronic pain, joint deformity and disability. "Chances are you know someone with rheumatoid arthritis, and if that person is in your family that means you have a higher risk of getting it too," Ms Koller-Smith said. "But steps like quitting smoking, maintaining a healthy weight, exercising, adding more omega-3 or fish into your diet and cutting down on sugar-sweetened drinks lower your risk of rheumatoid arthritis. "These are things people can do themselves or in consultation with their GP, and apart from making a real difference in reducing the risk of autoimmune disease, these lifestyle changes also have positive overall health benefits." UQ's Arthritis Queensland rheumatologist Ranjeny Thomas said while there was currently no cure for the disease, prevention was better than medication. "We now know that rheumatoid arthritis develops after initial triggering of inflammation in the lungs and gut," said Professor Thomas, Arthritis Australia Chair of Rheumatology at UQ's Diamantina Institute "This really brings immune system exposures, like smoking and what we eat and drink strongly into focus for prevention. "While we're working towards a cure, at the moment those who develop rheumatoid arthritis face lifelong medications." The research also involved UQ's Professor Ranjeny Thomas, Dr Ahmed Mehdi, Associate Professor Leigh Tooth, Professor Gita Mishra, and the University of Sydney's Professor Lyn March. It is published in the Internal Medicine Journal (DOI: http://dx.doi.org/10.1111/imj.15537).