Americans are hiding an eco-unfriendly secret in their bathrooms. It has nothing to do with the shower heads we use, or the gray water we waste and it has a greater impact on the environment than eating fast food in our Hummers. This secret, eco-sin, is our toilet paper.

In the United States, more than 98% of the toilet paper sold is harvested from virgin forests and this number is increasing. The New York Times reports that the demand for luxury toilet paper, the kind that has the greatest impact on the environment, increased 40% in 2008. So what should eco-conscious Americans do to help?

The easiest way for us to correct this trend is to take an example from our friends abroad. In Europe and Latin America, 40% of all toilet paper used is made from recycled paper. Taking note of this behavior, our first priority is to use the most eco-friendly product available. Recently, Greenpeace has stepped forward to make this job easier by providing a recycled tissue and toilet paper guide.

The amount of toilet paper we use is also an issue. Americans go through three times as much toilet paper as the average European and more than 100 times more than the average bathroom-goer in China. How do you do more with less? Here are a few quick tips:

Rely on the single ply: Single-ply toilet paper accomplishes the same thing as thicker options, but uses half or even a third less paper.

Roll it over, don't reach under: Setting the roll so that it flaps over the top, requiring you to tear from above, not below, the roll itself, encourages using less paper per-tear.

Pinch it to stop spinning it: Squishing the roll, so that the cardboard tube is an eye-shape instead of a circle, causes the paper to tear off at one or two sheet intervals, further encouraging reduced use.

For more tips on keeping your toilet paper green, don't miss these 9 green toilet paper tips.