By Froma Harrop / syndicated columnist

A federal health panel now recommends that men consume no more than one alcoholic drink a day. For 30 years, the Dietary Guidelines Advisory Committee set the limit at two drinks a day. (Women have long been urged to limit consumption to one drink a day.)

Other studies found that drinking under the previous two-beverage standard was actually good for the heart; and that moderate drinkers live longer than abstainers. So why was the earlier guideline chopped in half?

What we have here is a merger of several unfortunate habits in American policymaking where alcohol is concerned. One is a long-standing disapproval of drinking. Prohibition was a moral crusade that ended in fiasco 87 years ago. But there’s a modern version that gussies up the disapproval as a health matter.

Most everyone agrees that continuous heavy drinking can devastate one’s health and that addicts — alcoholics — should stop drinking altogether. But the new guidelines sloppily lump together excessive drinking with social drinking to make what was considered moderate consumption of alcohol look dangerous.

In response, five professors of medicine and epidemiology at Harvard sent a letter to federal officials expressing “serious reservations” about the new advisory. It complained that the committee cited a paper showing that “higher alcohol intake was associated with higher risk of all-cause mortality” but ignored other data in the same study that the researchers say demonstrate “a low-dose, high-frequency pattern was associated with significantly lower risk of total mortality.”

In other words, the guidelines didn’t distinguish between amounts being consumed. As the signers put it, “the original conclusion was biased by inclusion of binge drinkers who provide no evidence about the safety of within-guideline drinking.”

The guidelines are updated every five years by the U.S. departments of Agriculture and Health and Human Services. Three of the Harvard profs had previously served on the advisory committee.

This tightening of standards, The Washington Post notes, “comes during a pandemic when alcohol consumption — already at a 20-year high — is spiking further.” That may be, but what does one have to do with the other? We can well believe that some Americans have been drinking a lot more during the lockdowns. If there’s a problem, wouldn’t it be the “lot more” rather than the two drinks versus one?

That’s like saying the way to stop drivers from speeding at 90 miles an hour is to lower the speed limit from 60 to 50.

BMJ, formerly the British Medical Journal, recently published a study that listed moderate alcohol intake among the five low-risk lifestyle factors associated with longevity. Interestingly, the United Kingdom in 2016 lowered its limit for low-risk drinking; to 14 drinks a week for both men and women.

As for possible health benefits, researchers in Korea recently found a link between moderate drinking and lower levels of the protein that forms Alzheimer’s brain plaque, as reported in The New York Times. They defined moderate drinking as up to 13 standard drinks a week.

Famous studies tie moderate wine consumption to lower rates of cardiovascular disease and longer lives. Some of today’s crusaders argue that it isn’t the alcohol that’s conferring the benefits. Rather, wine drinkers tend to follow healthier lifestyles involving exercise, eating vegetables and social interaction. But even if these doubters are correct that a wine-drinking culture only enabled the good health habits, what’s wrong with that?

It is highly unlikely that those knocking down five glasses a night will pay the new guidelines any mind. The bothersome part is that men who enjoyed a bourbon and a cabernet with dinner might feel pressured to cut their pleasure in half; and for reasons little based on current science.

Follow Froma Harrop on Twitter @FromaHarrop. Email her at fharrop@gmail.com.