Feeling tired lately? Or perhaps you have had a cough or some kind of infection? You might even have a more serious problem such as diabetes or an ulcer. If so, you are not alone. We all get sick some times and need help.

For a surprisingly high percentage of the world’s population most of that help comes from medicinal plants. That is partly for cultural reasons and partly because they tend to be cheaper than drugs made by big companies. People also use plants to cure problems western medicine still cannot solve.

Many medicinal plants are readily available. Women grow them in their gardens or they grow naturally all around. However, some key plants are becoming scarce due to logging, over-harvesting and deforestation and that has put many families’ health at risk.

For nearly a decade, Patricia Shanley from CIFOR and Leda Luz from the State Forestry Institute in Minas Gerais, Brazil have been studying this problem in the Amazon. Their results, presented in "The Impacts of Forest Degradation on Medicinal Plant Use and Implications for Health Care in Eastern Amazonia" in Bioscience, are hardly reassuring.

The authors focus on the Amazon city of Belem and find that most of its 1.7 million inhabitants use medicinal plants to treat a wide range of ailments. The city’s markets, shops, pharmacies, gas stations, and curbside vendors sell more than two hundred different plants, of which about half grow naturally in the Amazon. The main downtown outlets alone make more than one million sales each year, generating several million dollars, and sales are growing fast. Some plants are just sold as is, but there is also a growing variety of capsules, powders, liquid medications, and shampoos.

Of the twelve top-selling medicinal plants in Belem, eight come from forests. Logging companies use five of those trees for timber and that has depleted their supply. Many important medicinal tree species are particularly vulnerable to logging because they grow slowly and occur in low densities. Fewer trees means less access for the rural poor and higher prices for medicinal tree barks, roots, and oils. That has made sick people’s lives much harder.

Politicians always like to talk about health care because they know it affects all of us. But they pay too much attention to white coats and high-priced drugs and not enough to the plants that so many people turn to when they get ill. To get the chainsaws out of our drugstores, that has got to change.