From the Editor

Leslie C. AielloPresident, Wenner-Gren Foundation for Anthropological Research

Roger BinghamCo-Founder and Director, The Science Network

G. Steven BurrillCEO, Burrill & Company

Arthur CaplanEmanuel and Robert Hart Professor of Bioethics, University of Pennsylvania

George M. ChurchDirector, Center for Computational Genetics, Harvard Medical School

Rita Colwell Distinguished Professor, University of Maryland College Park and Johns Hopkins Bloomberg School of Public Health

Drew EndyProfessor of Bioengineering, Stanford University

Ed Felten Director, Center for Information Technology Policy, Princeton University

Kaigham J. GabrielDeputy Director , Defense Advanced Research Projects Agency

Michael S. GazzanigaDirector, Sage Center for the Study of Mind, University of California, Santa Barbara

David Gross Frederick W. Gluck Professor of Theoretical Physics, University of California, Santa Barbara (Nobel Prize in Physics, 2004)

Lene Vestergaard Hau Mallinckrodt Professor of Physics and of Applied Physics, Harvard University

Danny Hillis Co-chairman, Applied Minds

Daniel M. KammenDirector, Renewable and Appropriate Energy Laboratory, University of California, Berkeley

Vinod KhoslaFounder, Khosla Ventures

Christof KochLois and Victor Troendle Professor of Cognitive and Behavioral Biology, California Institute of Technology

Lawrence M. KraussDirector, Origins Initiative, Arizona State University

Morten L. KringelbachDirector, Hedonia: TrygFonden Research Group, University of Oxford and University of Aarhus

Steven KyleProfessor of Applied Economics and Management, Cornell University

Robert S. LangerDavid H. Koch Institute Professor, Massachusetts Institute of Technology

Lawrence LessigProfessor, Harvard Law School

Ernest J. MonizCecil and Ida Green Distinguished Professor, Massachusetts Institute of Technology

John P. MooreProfessor of Microbiology and Immunology, Weill Medical College of Cornell University

M. Granger MorganProfessor and Head of Engineering and Public Policy, Carnegie Mellon University

Miguel NicolelisCo-director, Center for Neuroengineering, Duke University

Martin NowakDirector, Program for Evolutionary Dynamics, Harvard University

Robert PalazzoProvost and Professor of Biology, Rensselaer Polytechnic Institute

Carolyn PorcoLeader, Cassini Imaging Science Team, and Director, CICLOPS, Space Science Institute

Vilayanur S. Ramachandran Director, Center for Brain and Cognition, University of California, San Diego

Lisa RandallProfessor of Physics, Harvard University

Martin ReesProfessor of Cosmology and Astrophysics, University of Cambridge

John ReganoldRegents Professor of Soil Science, Washington State University

Jeffrey D. SachsDirector, The Earth Institute, Columbia University

Eugenie ScottExecutive Director, National Center for Science Education

Terry SejnowskiProfessor and Laboratory Head of Computational Neurobiology Laboratory, Salk Institute for Biological Studies

Michael ShermerPublisher, Skeptic magazine

Michael SnyderProfessor of Genetics, Stanford University School of Medicine

Michael E. WebberAssociate Director, Center for International Energy & Environmental Policy, University of Texas at Austin

Steven WeinbergDirector, Theory Research Group, Department of Physics, University of Texas at Austin (Nobel Prize in Physics, 1979)

George M. WhitesidesProfessor of Chemistry and Chemical Biology, Harvard University

Nathan WolfeDirector, Global Viral Forecasting Initiative

R. James Woolsey, Jr. Venture Partner, VantagePoint Venture Partners

Anton ZeilingerProfessor of Quantum Optics, Quantum Nanophysics, Quantum Information, University of Vienna

Jonathan ZittrainProfessor, Harvard Law School

Mariette DiChristina is editor in chief of Scientific American. Find her on Twitter @SAeditorinchief

BOARD OF ADVISERS

6 Scientific American, February 2011 Illustration by Nick Higgins

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The growing familiarity of the statistics does lit­tle to ease the painful realization of how disturb­ing they are. About a third of Americans are over­weight, and another third are obese—a jump from just 13 percent obese in 1962—and as a nation we

are growing fatter all the time. The excess weight has severe consequences. It causes more than 160,000 additional deaths in the U.S. annually and exacts a financial toll: health care for a person who is 70 pounds or more overweight can cost an additional $30,000 over a lifetime. Many other countries, in both the industrial and developing worlds, are seeing similar trends.

At the same time, in a crowded and en­vironmentally stressed world—with global population rising from 6.9 billion today to an estimated 9.3 billion in 2050—humanity is going to need to find sustainable sources of protein and nutrients.

In this edition, two feature articles take on the issues surrounding these very dispa­rate food challenges. Our cover story, “How to Fix the Obesity Crisis,” by David H. Freed­man, explains the complex web of factors—social, environmental, genetic and econom­ic—that led us to this situation. Someday science may find a pharmaceutical answer to weight gain. But until then, we have

only the currently available solutions that are best supported by research. What they are may surprise you. Turn to page 40.

Fish farms, as now practiced along coastlines, have had a con­troversial role in satisfying our hunger for seafood, given their track record of problematic environmental practices. With many

wild fisheries collapsing from commercial overharvesting and the continuing difficul­ties of sustainably raising livestock such as cows, pigs and chickens on land, however, we need better answers. Could new offshore fish farms—assuming they can function effi­ciently—be a productive direction to explore? Contributing editor Sarah Simp son’s report takes a look at that question. See “The Blue Food Revolution,” which starts on page 54.

Changing topics, I’d like to update you on two items that I mentioned in my letter last issue. We have now introduced an app for the iPhone, called Scientific American Ad­vances; we plan other mobile versions later this year. And by the time you see this issue, our first app for the iPad will be available for download. Called “Origins and Endings,” it tells compelling stories about the cosmos, life and human innovations through feature articles, videos, interactive informational

graphics, audio and slide shows from our archives. And as al­ways, we are eager to receive your feedback.

Too Much and Not Enough

New app for the iPad features stories about “Origins and Endings.”

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