If you’ve so much as sneezed in the past few months, you know that everyone and their grandmother is quick to offer you their immune-boosting, cold-busting secrets: foods to eat, foods not to eat, and vitamins and supplements with immune-boosting super powers.

But what actually works to ensure your immune system is strong enough to defend against illness and infection? We asked the experts to give us the lowdown on what actually works:

A healthy lifestyle is the key player
Sorry, it’s not as exciting as stuffing garlic cloves up your nose or spending a month’s rent on cold-pressed juice, but regular ol’ healthy habits practiced on an ongoing basis (not just when you feel that cold coming on) are the best things you can do for your immune system. “The best bet for good immune support is a healthy lifestyle,” says Morton Tavel, MD, author of Snake Oil is Alive & Well. “This includes good nutrition, regular exercise, and adequate rest.”

Eat smart
Let’s start with what you’re eating. Sure, one of the perks of adulthood is that no one tells you that you can’t eat ice cream for breakfast — but don’t make a habit of it. Deficiencies in micronutrients like zinc, selenium, iron, copper, folic acid, and vitamins A, B6, C, and E can mean trouble for your immune system, so make sure your diet is packed with micronutrient-rich foods like chicken, bananas, tomatoes, citrus fruits, seeds, healthy fats and oils, legumes, and whole grains.

Let’s get physical
Don’t worry, you don’t need six-pack abs to fight off a cold — just 30 minutes of brisk walking, cycling, swimming, or easy jogging three to five days a week is plenty, says Dr. Tavel. “More intensive programs are not necessary, and if extreme, may even be counterproductive.” “Exercise is a great immune booster,” agrees Scott Schreiber, DC. “It helps with stress, but also reduces weight, which are known to deplete immune system. In addition, exercise itself is an immune booster.”

A reason to hit the snooze button
All the yoga in the world won’t help if you’re constantly running on 5 hours of sleep per night. “Americans are chronically sleep deprived,” says Dr. Schreiber. Aim for seven to nine hours a night, he says. Adequate sleep might stop your runny nose before it starts, says Dr. Tavel. “When exposed to cold-producing viruses, people who sleep less than 6 hours nightly are more likely to develop colds in comparison to those who sleep for more than 7 hours.”

Curb bad habits
Not to lecture you, but if you light up, it’s time to stop. “Not only does smoking tobacco (and exposure to secondhand smoke) increase your risk for lung cancer, chronic lung disease, and heart disease, but it also makes it more difficult for the immune system to fight off invading infectious bugs, especially in the upper respiratory system,” says Dr. Tavel. Drinkers are not off the hook either. Too much alcohol can also take a toll on your immune system. Though researchers have found that drinking in moderation could actually be better than completely abstaining, it’s not a “more is more” kind of thing — drinking too much can produce a nutritional deficiency and inhibit white blood cells’ germ-fighting powers.

The stress connection
Stress and your immune system have a complicated relationship. In the short term (a few minutes to a few hours), stress can actually heighten our immune response — helping with functions like wound healing and preventing and fighting infection. Chronic stress, on the other hand, has the opposite effect — we’re talking that pain-in-the-ass boss, relationship issues, the all-nighters to finish up a big project…you know, life stuff. Since chronic stress can weaken the immune system, it’s important to keep that “life stuff” stress under control — yoga, meditation, and even social interactions all help, so go ahead and book a yoga schedule after brunch with your friends.

The deal with supplements
If it seems too good to be true, it probably is. Wisdom that applies to everything from Tinder to supplements. “Over 1,000 dietary supplements are actively being touted to boost immunity, but they are basically worthless to anyone except those reaping the profits,” says Dr. Tavel. The exception? Vitamin D. “[Vitamin D] does play role in aiding the immune system. Since older people are often deficient in this latter vitamin, especially those receiving little or no sun exposure, a daily supplement of 800 international units (IU) of vitamin D is worth considering.”

Just remember, you can have too much of a good thing. “Avoid mega doses,” cautions Dr. Tavel. That goes for other vitamins you’re taking too, especially vitamin A, folate, iron, and zinc — too much can actually hamper immunity, says Dr. Tavel, so follow your doctor’s guidelines.

The bottom line: The “secret” to a healthier immune system is a healthier lifestyle — focus on nutrient-rich foods, stress management, and exercise, not pills and concoctions that make big claims.

Diana Vilibert is a freelance writer and copywriter living in Brooklyn, NY. She loves flea markets, martinis, to-do lists, traveling, and wearing leggings as pants. You can see more of her writing at www.dianavilibert.com and follow her on Twitter at @dianavilibert.