It's that time of year when health questions focus on how to boost immunity to avoid catching a miserable cold or flu. Here's what you need to know!

Sniffle season has officially arrived, so you're probably scrubbing your hands and steering clear of coughing co-workers. But you also need to strengthen your immune system so you can battle the viruses that you do encounter.

Incorporate these research-proven tweaks into your daily routine, and we promise you'll spend fewer days sneezing this winter.

Top immunity boosters, # 1. Eat more mushrooms and broccoli

The next time you visit the salad bar, opt for these veggies. Mushrooms contain polysaccharides, compounds that may enhance the immune system's pathogen-killing activity, says Dayong Wu, Ph.D., a scientist at Tufts University. Additional research from the University of California, Los Angeles, reveals that sulforaphane, a compound found in broccoli, cabbage, kale, and cauliflower, can assist white blood cells in defending the body against free radical damage.

Top immunity boosters, # 2. Steal away for a quickie

Having a steamy love life may become your favorite way to ward off a cold. Researchers at Wilkes University found that women who had sex once or twice a week had 30 percent higher levels of the antibody immunoglobulin A (IgA) than those who didn't. "IgA is the body's first line of defense in fighting off infection," says researcher Carl Charnetski, Ph.D. "It binds to viruses entering the body and sends out signals for white blood cells to attack them."

Read on for more answers to your health questions about how to boost immunity, and discover three more top immunity boosters![header = Find three more top immunity boosters and answers to your health questions.]

You have questions about how to boost immunity, especially during the cold and flu season – and so Shape lists three more top immunity boosters.

Top immunity boosters, # 3. Log on to LinkedIn

Turns out your addiction to online networking sites has a surprising payoff. One study from Carnegie Mellon University shows that people who have larger social networks produce more flu-resisting antibodies than those with fewer friends. That may be because having people to turn to can buffer the effects of stress, which raises your risk of getting sick.

Top immunity boosters, # 4. Get tea-ed off

The polyphenols in tea boost the effectiveness of white blood cells. Harvard scientists found that people who sipped five cups daily secreted 10 times more interferon- proteins produced by the immune system to combat invaders-than those who drank the same amount of a placebo. "Even one or two cups a day offers valuable protection," says Jack Bukowski, M.D., Ph.D., the study's lead researcher.

Top immunity boosters, # 5. Nosh on nut

At the first sign of a sore throat, you probably stock up on oranges and other fruits high in vitamin C. But munching on vitamin E–rich almonds may bolster your immunity too. Researchers from Tufts University found that people who took a 200-milligram vitamin E supplement every day came down with fewer colds than those who swallowed a placebo pill. "Many women fall short of the recommended 15 milligrams of vitamin E daily," says Marisa Moore, R.D., an Atlanta nutritionist. She recommends taking a multivitamin and filling up on almonds as well as other foods high in the nutrient, like peanuts, wheat germ, sunflower seeds, and kiwifruit.