The Union of Concerned Scientists did a study to reveal that taking the bus is the greenest mode of transportation (other than walking or taking a bicycle) over planes, trains and individual automobiles when traveling city to city. According to the study, a couple traveling on a double-decker bus cut back their carbon emissions by as much as 75 percent versus flying or driving. The average miles per gallon on a full bus is 583, whereas a full flight has just 44 miles per gallon. And what's the number of individual cars one double-decker bus takes off the road? About 81. Now that discount bus services like Megabus come outfitted with Wi-Fi and power ports, it might be time to rethink the bus the next time you travel.

The Environmental Protection Agency has warned for years about limiting the amount of canned tuna we eat in order to avoid mercury poisoning. Children and pregnant women in particular should eat only around three 8-ounce portions per month if eating the canned white variety. A safer choice is canned light tuna, which has about one-third the parts per million of mercury in comparison, which is safe enough to eat once a week. An even better choice? The brand Safe Catch tests every fish for mercury before processing it, so it's almost guaranteed to be completely free of mercury with each flaky bite.

Many of us take vitamins and supplements on a daily basis to help us feel better or get the necessary nutrition we may be lacking. So it seems natural we could give these same natural supplements to cats and dogs to help them be healthy, right? Not so fast. According to the Food and Drug Administration, if your pet already eats a balanced diet, giving him more vitamins and minerals isn't necessarily a beneficial thing. Too much calcium can actually cause skeletal problems for large-breed puppies; vitamin A can harm blood vessels and cause dehydration; and vitamin D -- which gives humans energy -- can force your pooch to stop eating and his muscles to atrophy. Instead of risking it, ask your vet.