This week, the journal JAMA Internal Medicine published a study that should alarm social smokers, young and old—that cohort among us who “don’t smoke,” but bum a cigarette now and again…or who only smoke at parties, or in bars, or take just a puff now and again when friends go out to smoke, y’know, just to be social.

The authors, from the National Cancer Institute and the FDA, reviewed all-cause mortality data for 290,215 people between the ages of 59 and 82 in the NIH-AARP Diet and Health Study. People who smoked between one and 10 cigarettes a day, the researchers found, had a “substantially higher risk of premature death” than those who never smoked. “Okay,” you say, “half a pack—or even a handful of cigarettes—a day is still smoking. Understood.”

But notably, the researchers discovered that even those who consistently smoked fewer than one cigarette a day on average had a 64% higher risk of early death. When it came to lung cancer specifically, those who consistently smoked less than one cig a day throughout their adult life had nine times the risk of dying from the disease than never-smokers.

And in case you think vaping an e-cig can give you a risk-free fix, enter report No. 2: Just this morning the Surgeon General warned that the aerosolized nicotine products can lead not just to addiction but also to problems, in young vapers, of brain development and respiratory health.

Yet another medical review this week—this one in the prestigious Journal of the American College of Cardiology—found that people who drink very modest amounts of alcohol on a regular basis are at higher risk of experiencing an irregular heart beat (atrial fibrillation). Scores of studies in the past have shown that light to moderate intake of alcohol—“up to seven standard drinks per week for women and 14 standard drinks per week for men”—can have cardiovascular benefits for some people. This review—which, though not exactly a new finding, scoured the data from three large meta-analyses—offers a sobering counterpoint.

The poet Ralph Waldo Emerson advised that we weak mortals ought to practice “moderation in all things, especially moderation.” My personal take from this? Not even moderation is wise when it comes to smoking. And when it comes to the occasional drink, be moderate in the number of medical studies you read.