WHAT DO WE REALLY MEAN BY GREENGROWTH?The idea of "green growth"; like that of "sustainabledevelopment", and "addressing climate change",seems simple and positive. Go beyond the headline,however, and there are very different views of what thisterm really means. Whereas some see it as simplystating that economic growth needs to go hand-in-hand with environmental protection, others see it as anattempt to impose a particular economic model, and arestriction on the use of natural resources to supportdevelopment. In our view, the concept becomes clearer when we thinkabout the real bottom line of green growth -people.While nature is the original source of the resources andecological functions on which we all depend, andeconomies transform these into goods and services -the ultimate objective of green growth should be longer, healthier, better lives, for current and futuregenerations. We would do well to go back to the firstArticle of the Rio Declaration, and put humans back atthe centre of concerns for sustainable development.This should give us the guidance that we need both toconserve and manage natural resources, and ensurethat our economic systems genuinely work to sustainand improve human wellbeing.So far, we are not doing as well as we should. Despitethe economic growth of recent years, over 5 millionchildren still die every year. WHO estimates thatapproximately 25 per cent of all deaths and diseaseglobally are due to avoidable environmental risks -including urban outdoor pollution, indoor smoke fromthe burning of solid fuels and biomass in poorcountries; unsafe water, sanitation and hygiene;chemical exposure, occupational diseases, andclimate change. In other words, people suffer thesedisease burdens where we have not had enough "greengrowth" to both lift populations out of poverty, and toensure healthy environments.In pursuing green growth to improve human lives, weneed to recognise linkages between related problems,and look for synergies between different objectives. Forexample, addressing climate change will be achallenge for decades to come. But it is not a stand-alone issue -it will only be addressed by changing theways in which we achieve other goals, such asproviding transport, energy and housing. The aimshould therefore be to identify opportunities tosimultaneously provide these economic goods andservices, reduce our impact on the environment, andenhance human lives.GREEN AND HEALTHY GROWTH IN THEMODERN WORLDIncreasingly, these critical decisions will be made incities. The world is rapidly urbanising with significantchanges in our living standards, lifestyles, socialbehaviour and health. Thirty years ago, four out ofevery 10 people were living in cities, but by 2050 thisnumber will grow to seven out of 10, about 6.4 billionpeople in total, with most of the world's urbanpopulation living in Asia and Africa. Much of thispopulation explosion is currently happening in urbanslums, and much of the growth in urban land area isthrough horizontal, uncontrolled sprawl. This horizontal growth of cities and megacitiesdramatically increases the environmental health risksof urbanisation. It does so by making provision ofHEALTHBENEFITS OFGREENECONOMIC DEVELOPMENT044HEALTHDR MARIA NEIRA, DIRECTOR, DEPARTMENT OF PUBLIC HEALTH ANDENVIRONMENT, WORLD HEALTH ORGANIZATION" ""GREENER" DEVELOPMENTMODES FOR HOUSING, TRANSPORT ANDLAND USE NOTONLY CAN HELPREDUCE CLIMATECHANGE AND SUPPORT ENVIRONMENTALSUSTAINABILITY,THESE MODES ARE FAR HEALTHIER FORPEOPLE LIVING IN CITIES TODAY"Human beings are at the centre of concerns for sustainabledevelopment. They are entitled to a healthy and productivelife in harmony with nature."Article 1 of the Rio Declaration on Environment and Development, 1992

HEALTH045transport, housing, water, sanitation and energyexpensive and carbon-intensive, and generatingexcessive pollution from both transport and homeheating. Unsustainable patterns of land use, moreover,are stimulating unhealthy lifestyles, insofar as citiesare increasingly inhospitable environments forwalking, cycling, and physical activity. There is thus anurgent need to focus attention of health anddevelopment policymakers on shared solutions. Along with the risks, there are, however, opportunities.Housing, transport and the wider built environmentdeserve far greater attention in the health sector andamong development agencies as entry points forcontrolling a range of diseases, and simultaneouslypromoting "greener" economic approaches todevelopment. The evidence is incontrovertible:"greener" development modes for housing, transportand land use not only can help reduce climate changeand support environmental sustainability, these modesare far healthier for people living in cities today.Greener built environments in cities will also help toreduce the burden of important communicablediseases, including diarrhoea related to unhealthywater and sanitation; vector borne diseases; childhoodpneumonia and tuberculosis: There is also a majoropportunity to link health more effectively toenvironment and development policies in the contextof "green economy" strategies being developed in thecontext of climate change mitigation, the Rio+20conference on sustainable development, attainment ofthe Millennium Development Goal, and other globalhealth, environment and development initiatives. MEETING THE HEALTH CHALLENGESOF THE FUTUREWhile infectious diseases and malnutrition continue toexact a huge toll on public health in the poorestpopulations, the fastest growing health threats are nowfrom non-communicable diseases, such ascardiovascular diseases, diabetes, cancer and chronicpulmonary diseases. These are now increasing rapidlyin developing as well as developed countries.For non-communicable diseases, as in other areas ofpublic health "Prevention is better than cure". In thecase of non-communicable diseases, the keys toprevention lie not only in behavioural change, but inenvironments that protect and promote health. Greengrowth strategies in transport, energy, housing andworkplaces can be a "win-win" for health, forsustainable development, environment and climatechange. For example, investment in public transit,walking and cycling systems, and "transit-friendly"urban housing and land use, are strongly associatedwith improved health and reduced cardiovasculardisease and obesity in studies from both developedand developing cities. A systematic review of obesityinterventions has found urban transport andenvironmental measures to be one of the mostsuccessful areas with the most convincing evidence ofeffectiveness - more so than behavioural measures ontheir own (WHO, 2009). Multiple cost-benefit studies of public health gainsfrom walking/cycling infrastructure show health gainsto be five times the investment cost (Cavill et al,2008). Two large epidemiological studies, in Shanghaiand in Copenhagen, found that people commuting bycycling have about a 30 per cent lower risk of dying ina year than less active commuters - even after injuryrisks and other risk factors were considered (Matthewset al, 2007; Andersen et al, 2000).In addition, some 1.2 million people die from non-communicable diseases related to urban air pollutionevery year. (WHO, 2009). Urban vehicle traffic, inparticular, is an important and growing cause of thisdisease burden. Transport is estimated to account forabout 25 per cent of health-damaging urban airBelow: Dr Maria Neira