Some scientists predict that chocolate could be as rare (and expensive) as caviar in as little as 20 years. How could this be? Farmers have changed the way they grow cacao trees -- the source of the cacao seeds that are used to make chocolate -- to try to keep up with the world's increasing demand for chocolate. Cacao trees naturally grow in the rainforest, but because they grow faster in the sun, farmers now plant cacao trees in large, sunny fields. These trees produce cacao seeds earlier than their rainforest counterparts, but they are threatened by pests and a slew of nasty fungi. To protect their crops, farmers spray the trees with heavy doses of pesticides and fungicides. By the time the trees die, after about 30 years, the land has been completely destroyed by the heavy use of chemicals so the farmers must move on. They clear-cut a section of rainforest to create a new field and begin the process again. At this rate, scientists worry, cacao farmers will soon run out of fertile land. And we will run out of chocolate. However, help is on the way. Sustainable cacao farmers are heading back to the rainforest, where pollinators and natural pesticides help the trees thrive and eliminate the need for manmade chemicals. To support these farmers -- and keep chocolate plentiful -- buy chocolate from sustainable sources. Look for products that are stamped with the USDA Organic, Fair Trade Certified or Rainforest Alliance labels. And check out these brands, many of which can be found at your local grocery store or your nearest Whole Foods ( WFMI).