“As a routine bicyclist, I rarely drive anywhere in Boston, and I was reminded on my drive here why. It took me an aggravating 45 minutes to get a mile and a half,” he (eventually) told the audience at the Harvard Ed Portal.
Bernstein, who studies how changes in transportation, diet, and energy can immediately benefit health, lectured on “The Health Benefits of Going Green: How Reducing Greenhouse Gas Emissions Can Benefit Health Today” as part of the Ed Portal’s Faculty Speaker Series.
“In the context of doing things that will reduce our greenhouse gas footprint, there may be no better argument than an appeal to our own individual health. We can be no healthier than the environments we live in and the food we eat,” said Bernstein, the co-director for the Center for Climate Health and the Global Environment (C-CHANGE) at Harvard T.H. Chan School of Public Health. “But unfortunately you don’t have to look very far to find environments that are remarkably unhealthy.”
With the exception of smoking, poor diet and air pollution are the two leading drivers of disease across the world, according to Bernstein. Air pollution kills millions of people every year. Particulate matter — hazardous particles such as soot, smoke, and exhaust suspended in the air — are deadly, he said. In the U.S., particulate matter comes from burning fuels, especially fossil fuels, and in places like Boston much of it comes from burning gas and diesel.
Bernstein said people need to turn off their engines. “Stopping the use of fossil fuels emitted from cars will generate tremendous public health advances,” he said. “Car risks to health are not just about accidents and the air quality burdens they create. It’s also about the sedentary lifestyles they promote.”
Walking and bicycling decrease mortality, he said, while too much sitting contributes to poor health. Active people not only live longer, research shows that physical activity leads to greater productivity, happiness, and improved overall health.
Combined with lifestyle is diet — another crucial component in the sustainability movement. Nearly a third of the world’s population is now overweight, and an estimated 641 million are obese — an increase of 105 million people since 1975, according to a study published in the Lancet in 2014. The study estimated there will be 1.1 billion obese people by 2025.
Obesity is proven to increase risks for cancer, heart disease, kidney disease, high blood pressure, stroke, diabetes, and other diseases. Especially worrisome to Bernstein is the skyrocketing incidence of obesity in children.
“If a child is obese by age 10, they are very likely to be affected for life,” he said. “That’s a really big deal.”
Several factors contribute to these startling statistics, but two in particular have tremendous impacts on both human health and the environment, according to Bernstein. Large portion sizes and regular consumption of beef and processed meats such as bacon not only increase risks of mortality, but the production of beef also impacts the environment.
“The American diet has changed over the last two decades, and more people are dying in the world today from too much food, than too little,” he said. “Diet is not only a huge driver of disease in the U.S., it’s a huge part of the carbon footprint.”
So what can we do now to make people healthier and address the impact of climate change? Think about what’s within our control, both individually and collectively, Bernstein said.
“There are real benefits to individual health by simply reducing one serving of unhealthy food,” he said. “But it’s not just about diet, it’s about the bigger picture.”
Large-scale transformation of cities by electrifying vehicles, improving public transit, and creating more green space are crucial public health advances, he said. Planting trees is especially beneficial: They not only cool down cities, and so reduce heat-related mortality, they sequester carbon and reduce particulate matter air pollution. Rooftop gardens are also advantageous. They absorb excess rainwater, offer insulation, and provide food, all in an otherwise idle space.
“We are going to have a few more billion people on the planet and living in cities in the next decades,” Bernstein said. “Climate change is happening, and we need to think about city development in these healthy ways.”
Renewable energy can be another transformational factor, he said. Both solar and wind energy are water-efficient, non-carbon-intensive, and have low occupational hazards in production and installation. And, with their costs decreasing, Bernstein said the demand for these smart-grid energy resources is rising.
John Bruno of Allston came to the lecture because he felt connected to the topic.
“Many decades ago I was an economics major and an environmentalist,” he said. “We were talking about solar energy then, and now, 30 years later we have not really advanced as quickly in this area as we could have.”
Bernstein said the good news with renewable energy is that we are now doing what a decade ago would have been inconceivable. Knowledge has increased and technology is in place, it’s just underutilized, he said.
“If we do what we need to do to address energy, transportation, and food systems for our health,” he said, “we will actually help get climate change fixed at the same time.”