It never fails... Everything is going well, then one morning you wake up and it’s immediately obvious — You’re sick, complete with a scratchy throat, nose that’s stuffed up on one side and runny on the other, body aches, and watery eyes.

Fortunately, there are plenty of immune boosters on the market that promise to strengthen your body's defenses. But finding the right one can be overwhelming and confusing. 

That's why we’ve put together this guide — to help you understand what to look for and what to avoid when choosing one. And after extensive research, we've also compiled our top 5 immune boosting supplements on the market today. 

Key Ingredients To Look For In An Immune Supplement

Elderberry

Elderberry (Sambucus nigra) has been shown in extensive studies to boost immune health and help the body recover faster, working as perfect complement to Pelargonium sidoides. 

Vitamins C, D, & E

These three vitamins are essential for respiratory and immune health. Together, they help repair tissue, maintain normal cell health, and boost immunity. Because the lungs are such a sensitive organ — constantly changing and repairing itself — these vitamins are particularly important.

Marshmallow Root

Marshmallow root (Althea officinalis) is an herb that helps relieve the discomfort and aches caused by thick mucus and coughing. It is a natural source of mucilage, a lubricating compound that alleviates discomfort in the respiratory tract caused by excessive coughing.

L-Cysteine

L-cysteine is notable for its powerful ability to help support clean and healthy organ tissue. It has also been shown to promote white blood cell production and to help thin out mucus.

African Geranium

African geranium (pelargonium sidoides), also known as umcka, is a break-through, traditional herb clinically proven to help maintain a healthy immune system. Over 11 clinical studies have demonstrated how pelargonium sidoides works by stimulating immune cell function and by directly interfering with pathogens attempting to bind to your cells.

Beware: Too Much Zinc

Zinc is a popular ingredient in immune health supplements. However, if you take too much zinc (the upper limit appears to be close to 40 mg per day), you may feel unpleasant side effects.

That's why we recommend a dosage of between 11 and 25 mg per day, so you can still take full advantage of zinc without any of the effects of taking too much.

Your Immune Supplement Checklist:

Now that you know which ingredients to look for, it’s important to keep these additional tips in mind when shopping for an immune system supplement:

Clinically Recommended Dosages 

Some brands will use quality ingredients, but skimp out on dosages in order to save money. This means you won’t experience the full benefits. We recommend looking for a supplement that lists at least 80mg of African geranium and 600mg of NAC per serving.

Doctor-Formulated  

It takes specific expertise to form an effective immune health formulation. Look for real doctors specializing in immune health backing the product.

Money-Back Guarantee  

It’s always a good idea to invest in an immune system supplement that offers a 100% money-back guarantee. Look for brands that offer at least a 60-day money-back guarantee.

TOP 5 Immune Boosters

Using our ranking system and other research, here are the Smarter Reviews Picks for 2021's Top 5 Immune Boosters.