Science and Medicine

Researchers at Harvard University say America's obesity epidemic won't plateau until at least 42 percent of adults are obese, an estimate derived by applying mathematical modeling to 40 years of Framingham Heart Study data.

Researchers at Harvard University say America’s obesity epidemic won’t plateau until at least 42 percent of adults are obese, an estimate derived by applying mathematical modeling to 40 years of Framingham Heart Study data.

Their work, published this week in the journal PLoS Computational Biology, runs counter to recent assertions by some experts that the obesity rate, which has been at 34 percent for the past five years, may have peaked. An additional 34 percent of American adults are overweight but not obese, according to the federal government’s Centers for Disease Control and Prevention.

The Harvard scientists say that their modeling shows that the proliferation of obesity among American adults in recent decades owes in large part to its accelerating spread via social networks.

“Our analysis suggests that while people have gotten better at gaining weight since 1971, they haven’t gotten any better at losing weight,” said lead author Alison L. Hill, a graduate student in Harvard’s Program for Evolutionary Dynamics, Biophysics Program, and at the Harvard-MIT Division of Health Sciences and Technology. “Specifically, the rate of weight gain due to social transmission has grown quite rapidly.”

Read more: Obesity Rate Will Reach at Least 42 Percent

Colonized plant. (Credit: Image courtesy of University of Sheffield)

New research by scientists at the University of Sheffield has shed light on how Earth’s first plants began to colonize the land more than 470 million years ago by forming a partnership with soil fungi.

The research, published in Nature Communications, has provided essential missing evidence showing that an ancient plant group worked together with soil-dwelling fungi to ‘green’ Earth in the early Palaeozoic era, nearly half a billion years ago.

The research, which also involved experts from the Royal Botanic Gardens, Kew, Imperial College London and the University of Sydney, has provided new insights into our understanding of the evolving dynamic behavior of Earth’s land plants and fungi.

Scientists have long-suspected that soil fungi formed mutually beneficial relationships with early land plants to play an essential role in assisting their initial colonization of terrestrial environments. However, until now there has been a lack of evidence demonstrating if and how the earliest ancient land plants, from the early Palaeozoic era (over 470 million years ago), might have cooperated with fungi for mutual benefit.

Read more: How Ancient Plants and Soil Fungi Turned Earth Green