Holiday hugs and handshakes can spread more than good cheer. Unfortunately, warm greetings can lead to the transmission of cold-causing viruses.

If you're like most American adults, you'll catch a cold two to four times each year. With each infection, you can expect to spend around eight to 10 days under the weather: coughing, sniffling, sneezing and feeling miserable in general.

A visit to your doctor won't hurt, but it probably won't help that much, either. Although we've amassed a mighty arsenal of powerful drugs designed to fight the most dreaded diseases, we still haven't found an effective cure for the common cold.

Surprisingly, most of the symptoms associated with colds aren't caused by the cold virus itself — they're caused by the reaction of your body's immune system to the virus. The copious mucus secretions that make you cough, sniffle, snort and blow are a big part of the problem.

As early as an hour after cold viruses have infected the lining of your nose and throat, the invaded cells begin to release chemicals called prostaglandins. These chemicals produce swelling of the mucous membranes, leading to nasal stuffiness and congestion.

Prostaglandins also attract white blood cells to the site of the infection to battle the malicious microbes. As these disease-fighting cells report for duty, they begin to pile up by the millions in your nose, throat and chest, producing the massive flow of mucus that typically accompanies the common cold.

Most folks turn to over-the-counter cold formulas for relief of their symptoms, and there are hundreds available. Nonprescription cold remedies typically contain some combination of antihistamines, decongestants, cough suppressants and pain relievers.

None of these concoctions can stop the infection itself: They merely mask its symptoms. Even worse, some antihistamines and decongestants actually hinder the ability of the immune system to rid the body of the cold-causing virus.

If you're interested in making a speedy recovery, your best bet may be to steer clear of these conventional over-the-counter remedies and take a more natural approach. Recent research suggests that the mineral zinc and an herb known as echinacea may reduce both the duration and severity of cold symptoms.

Last year, scientists at the University of Connecticut reported that taking echinacea can reduce the duration of cold symptoms by an average of 1.4 days. Their study, known as a meta-analysis, evaluated the results of 14 previous clinical trials involving nearly 3,000 subjects.

The researchers also reported that echinacea appears to have powerful cold-preventing properties. When taken prior to exposure to cold-causing viruses, the herb reduced the risk of infection by an impressive 58 percent.

Although its mechanism of action isn't entirely understood, echinacea appears to have anti-viral properties as well as soothing, anti-inflammatory effects. The herb has been shown to stimulate the immune system, enhancing its ability to destroy disease-causing germs.

Like echinacea, zinc appears to bolster the body's immune response by triggering production of a natural virus-fighting substance called interferon. Some experts believe that zinc may act directly on the cold virus, preventing it from latching onto the cells in the respiratory tract and hindering its ability to multiply.

In a recent study conducted by researchers at Wayne State University School of Medicine in Detroit, cold sufferers using zinc lozenges shook off their symptoms in half the time of those who received placebo lozenges.

The study involved 50 volunteers who had experienced cold symptoms for 24 hours or less. Half the participants took lozenges containing 13.3 milligrams of zinc every two to three hours, while the other half took an inactive placebo.

Among individuals in the zinc group, the average duration of cold symptoms, including cough, runny nose and muscle aches, was about four days. Subjects in the placebo group fared worse: Their symptoms lingered for an average of seven days.

While over-the-counter cold remedies can cause a number of unwelcome side effects ranging from drowsiness to high blood pressure, zinc and echinacea are generally safe and well-tolerated when taken as directed.

The most common side effect associated with zinc lozenges is an unpleasant taste described as bitter or metallic. In sensitive individuals, echinacea can cause nausea and stomach upset.

Because there's no sure-fire cure for the common cold, preventing infection is especially important. Staying home when you're sick and washing your hands regularly will help you enjoy holiday greetings without giving — or receiving — cold-causing viruses.

Rallie McAllister is a board-certified family physician, speaker and the author of several books, including "Healthy Lunchbox: The Working Mom's Guide to Keeping You and Your Kids Trim." Her website is www.rallieonhealth.com. To find out more about Rallie McAllister, M.D., and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate Web page at www.creators.com.