Aside from pesticide usage and a few other issues, most of us haven't worried much about the connections between health issues and the environment. For our health, we work on our waistlines and fret over our cholesterol levels. For the environment, we recycle and maybe drive a fuel-efficient car.
But because of accelerating climate change and the havoc it could wreak, it's not so easy to send environmentalism off into its own separate compartment these days. In February, the Intergovernmental Panel on Climate Change said the evidence for global warming is "unequivocal." Everything we do now can be measured for its effect on the environment — and greenhouse gas emissions in particular.
There's always danger in doling out "what you can do" advice. Bite-size solutions sometimes trivialize larger problems. We end up doing easy things because they make us feel good, not because they do much good. Policies set in Washington and elsewhere are far more important.
Still, there's a place for individual responsibility — and certainly for voting with our dollars. "The real answers are not going to come from individual action, but I do think that individual actions can have ripple effects," says Dr. Paul Epstein, associate director of the Harvard Medical School's Center for Health and the Global Environment. "We can educate our friends and colleagues and work to change the practices of employers, schools, even places of worship. As individuals, I think we can set in motion new patterns of sustainable consumption and help create markets for clean, efficient technologies."
We thought we'd bring personal and environmental health together and provide nine “green” health tips.
1. Walk or bike to work. At a bare minimum we're supposed to get 20–30 minutes of exercise most days of the week. The Institute of Medicine says that isn't really enough and recommends a full hour of moderately intense activity a day (biking and walking at a 4-mile-per-hour clip meet the moderately intense standard). But we're a nation of drivers, not walkers or bikers, and almost every driving statistic you can think of is headed in the direction of a hotter planet. The average fuel economy of new cars has declined since 1988 because of the popularity of minivans and SUVs. Vehicle miles traveled per person have grown twice as fast as the American population in recent years. Households with four or more cars now outnumber those with no car. And the proportion of commuters who carpool or walk or bike to work has slid since 1980, while the percentage of those driving alone has crept up from 64% to 76%. Could there be a better good-for-you, good-for-the-planet twofer than the walking or biking commute? Combining exercise and a commute builds exercise into your day, which means you don’t have to summon extra willpower, to say nothing of time, to go to the gym. If you live too far away, consider walking or biking to public transportation or driving only part of the way.
2. Go to bed early. Americans weigh more and are sleeping less. Average daily sleep time has decreased from about nine hours a century ago to about seven now. Epidemiologic studies have identified a correlation between short sleep and being overweight or obese. Hormones may be why: Lack of sleep depresses the levels of leptin, the hormone that tells the brain we're full, and increases ghrelin, the hormone that makes us hungry. Meanwhile, all the lights, televisions, computers, microwave ovens, and music players that help keep us up at night use electricity, most of it generated by burning coal and natural gas. Household use of electricity has increased by over 50% since the early 1980s. By turning in earlier, we'll dial down our appetite for kilowatts and maybe food.
3. Turn down the heat and the air conditioning. Humans, like other mammals and birds, control their body temperature by continually adjusting their metabolisms. When the air is cool, metabolism revs up to produce more heat. When it's hot, sweating and other responses also burn up extra energy. But when air temperatures are in the thermoneutral zone (TNZ) — which for humans with their clothes on tends to be in the mid-70s — our metabolisms don't have to work so hard to maintain body temperature, and we burn fewer calories. We're spending more time in our TNZs these days because of heating and — particularly — air conditioning. Some experts believe all that time in the comfort zone is contributing to the obesity epidemic. The amount of energy used to heat American homes has actually declined a little bit since 1978, the result of better insulation, more efficient furnaces, and, yes, warmer winter temperatures because of global warming. But the amount of electricity used to cool homes has almost doubled in that span. So by adjusting your thermostat, you may keep your metabolism from getting lazy and also use less of another kind of energy.
