They come from all walks of life, but members of this group have one thing in common: They want to shed weight.

But this weight isn't the usual 10 pounds many people want to lose; these weight watchers want to cut thousands of pounds of carbon produced each day as we go about our lives, doing everything from laundry to driving cars.

Most carbon our activities generate ends up in the atmosphere as carbon dioxide, where scientists say it helps to create a greenhouse effect by trapping heat from the sun.

Some scientists say the negative effects of this trapped heat include rising sea levels as polar ice melts, severe droughts and rising temperatures worldwide.

The group, which has been meeting about every two weeks since the beginning of June at the Allegheny Unitarian Universalist Church on the North Side, is using as its guide a book called "Low Carbon Diet -- A 30-Day Program to Lose 5,000 Pounds" by David Gershon.

Applying techniques often employed by successful diet programs to carbon reduction, the book outlines a step-by-step program to lower carbon dioxide emissions. It says the average American household produces 55,000 pounds of carbon dioxide annually, while the typical German household emits 27,000 pounds, and a comparable Swedish household, 15,000 pounds.

Those emissions come from lighting, heating, air-conditioning, appliance use, even the amount of garbage we produce. About 1 pound of carbon dioxide is released for every pound of garbage as it decays in landfills

Crucial to the success of the program is meeting regularly.

"The concept is a great idea because you can learn from other people. Being with the group makes you want to do something," said Helen Ortmann, of Brookline.

Jeanne Zang, of Edgeworth, said she likes the idea of being with other people who are so enthusiastic.

"We support each other and encourage each other to make changes. It's been very effective," she said.

Tim Nuttle, of the North Side, introduced the concept to church members after researching the carbon effect of everyday activities for an ecology class he teaches at the University of Pittsburgh, where he is a research assistant professor.

The group is open to anyone.

Reducing electricity consumption is an important element in the low carbon diet because electricity use is responsible for about 16,290 pounds of yearly carbon dioxide emissions from every American household, according to the federal Environmental Protection Agency.

At a recent meeting, Ms. Zang, demonstrated a combination radio and LED flashlight that doesn't use electricity but is powered by cranking a lever on the side.

The group will hold an open meeting at 7:30 p.m. Wednesday at Allegheny Unitarian Universalist Church, 1110 Resaca Place, North Side.