Holiday Health Myths: Sugar, Suicides, and Cold-Weather Clothes

The holiday season is a great time for family, friends, and well, old wives’ tales: Who hasn’t been told to wear a hat because you lose the most heat from your head?

There are some real holiday health hazards (see 11 of them here). But an analysis in the British Medical Journal suggests that your mother’s—or even your doctor’s—holiday hazards often lack rock-solid evidence to back them up.

Rachel Vreeman, MD, and Aaron Carroll, MD, of the Indiana University School of Medicine, did a reality check by poring over the medical literature and doing Google Internet searches.

Here’s what they found.

Release the candy canes! Children who eat sugar act no differently than those who have none, according to 12 placebo-controlled studies.

One study found that when parents thought their children had been given a sugary drink (it was sugar free), they rated their child's behavior as hyperactive.

“A lot of occasions when kids are exposed to sugar are when they are most likely to be super excited, running around, and acting out,” says Dr. Carroll.

Other research has hinted that

artificial dyes and preservatives may be a problem, not sugar.

While the holiday season is a joyful for many, it can also be stressful or depressing. But a 35-year study on Minnesota residents found that suicides did not increase on or around Christmas or any other major holidays, including birthdays, Thanksgiving, or the Fourth of July.

Research from all over the world, in fact, shows that suicides are actually more prevalent in warm, summer months—a pattern that scientists can’t quite explain. While

suicidal thoughts should be taken seriously at any time of year, there’s no reason to think that this month is especially dangerous.

A 1996 analysis of 22,793 poinsettia cases reported to the American Association of Poison Control Centers revealed no significant poisoning.

It's possible to become ill by consuming a large amount of the plant, but it’s rare, even in small children and pets, says Edward Krenzelok, PharmD, director of the Pittsburgh Poison Control Center and Drug Information Center at the University of Pittsburgh.

Some studies suggest that poinsettia sap can be irritating to the skin.

An old military study found that people in Arctic survival suits (but no hats) did lose a great deal of heat from their heads. But if you wore a swimsuit, you'd lose heat evenly across exposed body surfaces—and no more than 10% from the head.

“We often hear parents say that as long as their kids are wearing a hat, they feel that they’re sufficiently dressed,” says Dr. Vreeman. “Of course they should bundle up for protection from the cold, but they should be equally concerned about gloves and boots as well.”

There's no research to support the belief that eating before bed causes more weight gain. There are benefits of eating meals at consistent times, but only because it helps limit overall intake of daily calories.

“The time of day a person eats is not as important for overall weight gain as the amount of calories eaten during the day,” says Jeannie Gazzaniga-Moloo PhD, RD, a spokesperson for the American Dietetic Association. Avoid your favorite go-to comfort foods before bed, she says, but don’t fret if your dinner gets pushed back a few hours.

Sorry, but there’s no magic bullet for this one. Internet searches reveal seemingly endless options for hangover cures, the authors report, from aspirin and bananas to prickly pear and Vegemite.

But no large, well-designed studies have found that anything but time—and drinking water to treat dehydration—can ease the aftermath of too much alcohol consumption.

However, if you drank—or ate—too much over the holidays, try these

detox recipes that will put vital nutrients back into your diet.

The authors’ analysis—which was not a systematic review—was performed mainly for entertainment reasons. “Plus,” adds Dr. Vreeman, “we don’t want people going outside with just hats and no other clothing.” However, the authors stress that there is a larger lesson to be learned.

“With the Internet today, it’s easier to find good information but it’s also just as easy to find bad [information],” says Dr. Carroll. Advice is often passed by word of mouth, even by medical professionals. “Doctors spend a lot of time simply doing things they’ve been told to do or things they’ve learned in the past.”