Staying fit and eating whole foods—along with getting sleep and regularly washing your hands—are some of the best ways to keep the sniffles and sneezing away.

But when a hectic schedule starts wearing you down, a little immune system boost may be in order. Here’s what the latest research shows when it comes to helping you sail through cold and flu season.

Scroll through for some cutting-edge supps that could help enhance your immune system...

1. Elderberry

This flavonoid-filled fruit is thought to work by reducing congestion and upping perspiration. One study in Alternative Medicine Review found that elderberry extract reduced the length of flu symptoms by almost three days.

“Elderberry has also been shown to help kill viruses, and it contains anthocyanins, plant compounds known to help support the immune system,” says Kamal Patel, M.P.H., director of examine.com, an independent encyclopedia of supplementation and nutrition.

Use it: Available in capsules or liquid.

2. Probiotics

Probiotics—or beneficial bacteria—are known for helping with gut health, but one of their lesser-known possible benefits is immune regulation.

“Around 70% of our immune system cells are actually in our gut, and probiotics could help make our guts healthier Opens in a new Window.,” explains Patel. But because each probiotic strain may have different attributes, experts aren’t fully clear on which probiotic can do what.

There is evidence that both the Lactobacilli and Bifidobacteria strains may reduce the symptoms of some allergic diseases.

Use it: In capsules or in food like yogurt and kefir; one to 10 billion colony-forming units a day for up to two weeks.

3. Spirulina

This blue-green algae often pops up in those greens powders that are chock-full of health claims, but there is evidence for a variety of potentially helpful uses, including immunity, says Patel.

Though there hasn’t been much human evidence, one 2008 study showed that taking two grams of spirulina a day for a few months helped people with nasal allergies.

“Spirulina is pretty safe, and it may also lower systemic inflammation to help with general health,” he adds.

Use it: In capsules or pills, 1 to 8g a day

4. Tinospora Cordifolia

This Ayurvedic herb has a variety of purported benefits, from regulating blood sugar to enhancing the immune system.

“Tinospora cordifolia can help a type of immune cell called a macrophage to more easily consume the germs that we don’t want in our bodies,” says Patel.

The best evidence for this herb is for warding off allergies, but if you take medications that interact with MAO inhibition, check with your doctor before taking this herb.

Use it: As a water extract or mixed with ghee and ginger; 300mg of extract three times a day, or 10 to 15g a day of the mixture.

5. Garlic

Numerous studies have shown that garlic is antiviral and anti-inflammatory, which can stimulate the immune system.

The cloves release a compound called allicin when it’s sliced or chopped, but you should let it sit for about 15 minutes after preparing to allow maximum amounts to form.

A study published in the journal Advances in Therapy reported that subjects taking a garlic supplement had fewer colds and less sick time.

Use it: 1 to 2g sliced garlic cloves or 600 to 1,200mg garlic extract twice a day. 

6. Vitamin C

There’s evidence this classic cold fighter can help boost immune function, but taking massive doses once you have a cold won’t hasten your recovery.

Vitamin C is important for a properly functioning immune system, and not getting enough vitamin C may be putting you at risk, says Patel. One 2013 meta-analysis of 30 studies and more than 11,000 people showed that those living with episodes of high stress, like marathon runners, were 50% less likely to catch colds if they took a daily supplement of 200mg of vitamin C.

Use it: Find C naturally in pills or foods like sweet peppers, berries, and oranges; or take up to 250mg a day in supplements (RDA is 75mg daily for women over age 19).

7. Zinc

This essential mineral is needed by the immune system to function at an optimal level, says Patel, and studies have shown that taking zinc can help to reduce the duration of colds.

A 2016 meta-analysis published in the British Journal of Clinical Pharmacology found that cold symptoms in subjects taking zinc lozenges cleared up in nearly three days, compared with seven days for those who took only a placebo.

Use it: As a lozenge (avoid using sprays, which are known to affect the sense of smell); 4 to 25mg every three hours for three to 14 days.