Suggestions for how to be healthy and 'green'
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.
4. Eat fish, but the right kind. Fish needs no introduction as a healthful food, especially in these pages. As the main food source of long-chain omega-3s, it's good for your heart and probably your brain. But the sterling health credentials have some environmental tarnish. Some species are contaminated with pollutants — mercury and PCBs are the main concern. Stocks of others have been dangerously depleted by too much fishing. Some groups are working to steer consumers to species that are in good supply. The Marine Stewardship Council, a British group, certifies fisheries as sustainable. Environmental Defense, a New York-based environmental group, has posted a helpful list of best and worst fish choices at www.oceansalive.org. The Blue Ocean Institute has a useful guide at www.blueocean.org/seafood. But making the right "eco-choice" does involve some homework — maybe a bit too much for many of us. Take swordfish. It's on every list of mercury-contaminated fish but it's also a good source of omega-3s. Once scarce, populations are almost fully recovered in the North Atlantic, according to the Oceans Alive Web site, and the United States has strict rules for swordfish fishing in the Pacific, where fishing practices threaten endangered sea turtles. But foreign fleets don't have to follow those rules, so not only would you need to know which ocean your swordfish came from to make an environmentally sensitive choice, you'd also need to know the origin of the fleet that caught it.
5. Switch to energy-saving light bulbs, but don't throw them in the regular trash. Those curlicue compact fluorescent light bulbs that Home Depot wants you to buy are the real deal. They use two-thirds less energy than a regular incandescent bulb and last up to 10 times longer. The Natural Resources Defense Council, a mainstream environmental group, estimates that each compact bulb keeps half a ton of carbon dioxide out of the air over its lifetime. But all fluorescent bulbs need mercury to work, and the compact versions contain about five milligrams of the metal. That's not much — an old-fashioned home thermometer contains a hundred times that amount — but if you throw them out in the regular trash, that mercury may end up in the air or water, and, by climbing the food chain, in the fish on your plate. The environmentally good deed you performed by buying the light bulbs would be completely undone by the way you got rid of them. Call your town or city's public works department to find out where you can dispose of fluorescent light bulbs safely. A corporate-sponsored Web site, www.earth911.org, lists businesses and local governments that handle household hazardous waste.
6. Learn a lesson from palm oil and good intentions gone awry. As the tide turns against trans fat, food manufacturers are scrambling for substitutes. Palm oil has emerged as a candidate. Some varieties of trans fat–free Oreos are made with palm oil and another trans fat replacement, high-oleic canola oil. In Europe, palm oil has also been touted as an environmentally friendly renewable "biofuel" alternative to fossil fuels like coal and gas. But to satisfy the growing demand for the tropical oil, huge tracts of Southeast Asian rainforest are being cut down and planted with palm trees. Farmers are also draining and burning huge swathes of peatlands, which help offset greenhouse emissions by soaking up carbon. The New York Times described palm oil as a green fairy tale that is beginning to look more like an environmental nightmare. Palm oil is an improvement over trans fat as far as personal health is concerned, but that's not saying much. About half of the fat molecules in palm oil are saturated, and saturated fat increases cholesterol levels. The moral of the story is not to be dazzled by alternatives in either the environmental or personal health realms. They, too, may have dark sides. As best we can, we need to look before we leap.
7. Eat local fruits and vegetables. By all means, eat fruits and vegetables. Good health depends on it. But Michael Pollan's book The Omnivore's Dilemma raises some questions about the means by which we get them. Flying kiwis in from New Zealand and grapes up from Chile is an energy-intensive way to fulfill the fruit-and-vegetable imperative. It's possible only if energy is cheap, and cheap energy in this fossil fuel–era of ours means tons of greenhouse gas emissions and global warming. The Pollan book has inspired the buzzword "food miles" — how far food has been transported to reach our plates. "Local and sustainable" is flaunted as a virtue on restaurant menus. Some economists take issue with putting "local" on a pedestal. Their point: Global trade may entail high transportation costs, but it also organizes food production to occur where it's most efficient. Besides, isn't it wonderful to have fresh produce out of season? The reasonable middle ground is to give some preference to locally grown food. Is that shiny Granny Smith apple from New Zealand worth the greenhouse emissions when a Macintosh from a nearby orchard might do? And shopping at farmers' markets is a good way to reduce your food mileage. You'll be even "greener" if you walk or bike there.
8. Don't take more medications than you need to. In most cases, our bodies use only a fraction of any drug we take. The rest gets excreted, but it doesn't disappear once we've flushed. Scientists are still sorting out which drugs are causing significant harm and at what levels. But there's already evidence that pharmaceuticals in waste water adversely effect aquatic ecosystems. In 2005 Swedish environmental scientists reported that some beta blockers and antibiotics, and carbamazepine (Tegretol, other brands), an antiseizure medication, seemed to be especially persistent in a small river in the southern part of the country. All drugs have side effects, so for your own health, you should take medications that are necessary but no more. Now the environmental consequences may be another reason to be prudent in your pill intake. And if you've got old medications, don't flush them down the toilet. Leave them in the container and throw them in the regular trash, although be sure to scratch off any identifying information for privacy reasons. Mix a little cat litter into liquid medicines and put some water in pill bottles.
9. Get behind the greening of hospitals and medical buildings. American hospitals are on a building spree that rivals the post–World War II boom. Hospitals aren't getting bigger — the number of beds is declining. But they're getting more deluxe, with additional private rooms and more sophisticated technology. Health economists worry that these gold-plated facilities will put further pressure on health care costs. In some cases, though, hospitals are seizing the opportunity to build "greener" buildings, which have attributes that may also improve the health and well-being of patients. Building a hospital or nursing home with more natural light not only saves energy but may also enhance the mood of patients (and staff!) and keep them more oriented. Some hospitals are taking steps to improve indoor air quality with proper ventilation and use of materials that don't emit volatile organic compounds. As individuals we can't go build a green hospital the way we can buy an energy-efficient car. But we can encourage their construction by writing a letter (hospitals are very public relations conscious) and supporting policies and programs that encourage energy-efficient construction.
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