By now it's well known that the nation ruled with increasing autocracy by President Vladimir Putin is experiencing one of the most rapid and catastrophic declines in human health ever recorded in peacetime. Life expectancy for Russians is plunging, rates of accidents and disease are soaring, and an AIDS epidemic is incipient.

What's less well known is that right next door, another Slavic nation with a traditional affection for vodka -- Poland -- is experiencing one of the greatest improvements in health ever known. The difference tells a story of how democracy has transformed the center of Europe in the past 15 years -- and how it has failed in Russia.

Start with the figures. In the early 1980s, life expectancies in Soviet Russia and Communist Poland were roughly similar, and both were starting to get worse. Cancer and cardiovascular disease were beginning a rapid rise, in lock step with their prime causes: smoking and alcoholism.

Two decades later, Poland's life expectancy for men, at 70, has risen by four years since the collapse of communism and now is more than 10 years longer than that of Russian men. In Poland, cardiovascular disease has fallen by 20 percent in a decade, while in Russia, it has risen by 25 percent. Sudden deaths from accidents and other external causes have fallen 19 percent in Poland, while in Russia the rate has soared to an unprecedented level. Poland's rate of HIV infection is one of the lowest in Europe; Russia has one of the world's highest rates of new infection.

Witold Zatonski thinks he knows the reason for this extraordinary divergence. A Warsaw-based epidemiologist who has spent decades studying, and crusading for, public health in Poland and its near neighbors, he has boiled his answer down to a simple slogan: "Democracy is healthier." "It's the only way to explain what has happened," he said during a recent visit to Washington. "It turns out that the free-market economy and a free political debate correlate directly with good health in Eastern and Central Europe."

That conclusion used to be doubted by some of Zatonski's colleagues, both in Poland and in the West. After all, democracy brought Poland freedom for cigarette and alcohol advertising, Western brands, and a parliament presumably susceptible to special interests. Tobacco companies spent $100 million a year on marketing to Poles in the 1990s.

Remarkably, though, all that money and influence have been outweighed by the other products of a free society, especially independent civic organizations and media that promote knowledge and open debate about health issues.

When I first met Zatonski, in 1986, he was a quixotic anti-smoking crusader barely tolerated by the Communist government and unable to organize public campaigns or influence the state-run tobacco and alcohol monopolies. But with the coming of democracy in the 1990s, he was able to set up a civic movement that organized national anti-smoking campaigns, attracted abundant attention from newly independent media, and eventually persuaded the elected parliament to pass far-reaching restrictions on cigarette advertising and sales. Cigarette smoking, which had risen steadily since World War II, fell by 10 percent in Poland in the 1990s, despite the invasion of Western companies.

Poles were meanwhile learning from their media that vegetable oil was more healthy than animal fat or butter, and finding much more of it available in their markets. Fresh fruit and vegetables became available year-round for the first time in decades, and the new civic groups for women -- or parents, or dieters -- springing up everywhere promoted their consumption. Many drinkers switched from vodka to beer and wine. Private gyms opened, and exercise became fashionable. Cardiovascular disease, Zatonski says, underwent "the greatest decline in the history of mankind."

And not only in Poland. Zatonski's figures show a stark divide in the former Eastern Bloc between countries that have embraced democracy and sought integration with the West and those that have remained autocratic. In addition to Poland, the Czech Republic, Hungary and other newly democratic states have recorded dramatic gains in health. But Ukraine and Belarus, which have followed Russia's political course of far more restricted freedom, have seen their health measures decline. The Baltic states of Latvia, Lithuania and Estonia, which were once republics of the Soviet Union, at first shared Russia's downward spiral; but since 1995, as they have built Western-style democracy, they have reversed the trend and now follow Poland's path.

Not every country has a public health campaigner as able or energetic as Zatonski. But his career demonstrates that such people are less important than the political environment around them. Zatonski's studies show that the man most important to Russia's health is not a doctor, but Putin -- and that his consolidation of power likely condemns his country to grow still sicker.

Jackson Diehl is a columnist for The Washington Post, where this comment first appeared.