Tiny microorganisms dangerous to our health are all around us. Pathogens like the cold, the flu, and COVID-19 may be lurking on grocery store baskets or in the air that we breathe.

When pathogens infiltrate our first line of defense and enter the body, our immune response determines whether or not we succumb to illness. When your immune system is robust, it’s able to subdue pathogens before they make you sick. But when it isn’t, it’s only a matter of time before you become ill.

One of the best ways to boost your immune function and safeguard your health is to take in vitamins, minerals, and herbs proven to bolster immune strength. In this article, we’re going to reveal 7 of the best supplements for optimal immune health.

#1: Elderberry

Elderberry’s ability to protect the body against illness has been recognized for thousands of years. (1) The “father of medicine” Hippocrates encouraged its use in herbal medicine in 400 BC, and countless natural practitioners have continued to do so to this day.

Elderberry exhibits antibacterial and antiviral properties. In a 2004 study published in the Journal of International Medical Research, researchers examined the effect of elderberry extract on the influenza virus in humans. (2)

Sixty patients with flu-like symptoms were given either a placebo or elderberry extract within 48 hours of developing symptoms. On average, those in the elderberry group were sick for four fewer days than those in the placebo group.

To reap the immune-boosting benefits of elderberries, try an elderberry extract. You can use it daily for times when you’re worried about getting sick, or from the onset of symptoms.

#2: Andrographis

Andrographis, also known as “Indian echinacea,” has been used as a medicinal herb across the globe for centuries. (3) Researchers have found that compounds within Andrographis enhance immune function. (4) Because Andrographis exhibits immune-stimulating properties, it supports a strong immune response against illness.

For instance, when a virus enters the body, it must invade host cells to replicate. Only after cell invasion and replication can the virus spread throughout the body and cause illness. By bolstering the immune response, Andrographis may help the body stop viral proliferation, avoiding sickness.

#3: Spirulina

Algae is a superfood that’s a go-to for health aficionados. As the food source responsible for much of salmon’s health benefits, algae is something everyone should be eating.

Spirulina is a blue-green alga once called the “best food for the future” by the World Health Organization. (5) Thanks to spirulina’s nutritional benefits, it’s been used as a supplement by NASA astronauts while in space.

This nutritional powerhouse is our favorite alga for anyone seeking immune benefits. In human studies, spirulina has demonstrated an immune-boosting effect in patients with allergies, hepatitis C, HIV, and even in healthy athletes. (6,7,8,9,10)

You can find various spirulina supplements, although powders and capsules are the most common. Try adding one teaspoon of spirulina to a daily superfood smoothie.

#4: Garlic

Most of us consume garlic regularly in the form of garlic powder or cooked garlic in savory dishes. However, it’s raw garlic that has the most significant impact on immune function. (11) When raw garlic cloves are crushed, the compound allicin forms. Once consumed, allicin generates multiple compounds that benefit human health.

Researchers from the United Kingdom published a study in Advances in Therapy that examined the effect of garlic on the common cold. (12) One hundred forty-six participants took either a daily garlic supplement with 180 mg of allicin or a placebo for 12 weeks. Over the trial period, the participants who took garlic experienced significantly fewer cold episodes than those who took the placebo.

Garlic appears to enhance immune system function by stimulating multiple types of immune cells and modulating immune activity. (13) To get the maximum benefit, be sure to chew raw garlic or buy a garlic supplement with allicin.

#5: Vitamin C

You’re probably familiar with vitamin C seeing as it’s one of the most widely-used immune-boosting supplements. Its abundance of antioxidants is to thank for much of its positive impact on the immune system. (14)

Vitamin C stimulates immune cell production and overall immune function. One of the major impacts of vitamin C on the immune system is that it’s involved in the production of neutrophils. Neutrophils are immune cells that target viruses and bacteria. As such, vitamin C is particularly advantageous during times when viruses are prevalent, such as flu season.

It’s possible to get enough vitamin C through diet alone. The key is eating generous portions of brightly colored fruits and veggies. The following each contains greater than the recommended daily value of vitamin C:

  • 2 kiwis (raw)
  • 1 cup strawberries, halved (raw)
  • 2 oranges (raw)
  • 1 ½ grapefruits (raw)
  • ½ cup yellow pepper (raw)
  • 1 ½ cup chopped kale (raw)
  • 1 cup Brussels sprouts (cooked)
  • 1 cup broccoli (cooked)

To ensure sufficient daily vitamin C, enjoy a berry-filled morning smoothie or a kale salad. Alternatively, you can concentrate on regularly eating fruits and veggies. With all fruits and vegetables containing vitamin C, a healthy eating approach almost guarantees that you’ll get enough.

Vitamin C should be consumed daily. For times when you aren’t able to get sufficient vitamin C through diet, or when you feel like you might benefit from an extra dose, try a daily vitamin C supplement.

#6: Vitamin D

When you bask in the sun, your body synthesizes vitamin D. Unfortunately, few of us get sufficient sun exposure throughout the year. Winter months and long hours working indoors make it hard to create enough vitamin D from sunlight.

Vitamin D regulates the expression of genes involved in our immune response. (14) What’s interesting about vitamin D is that it modulates the immune system. In doing so, it both strengthens a weak immune system and protects the body against an overactive immune response.

Multiple studies have found vitamin D supplementation to play a preventive role against respiratory infections caused by common viruses like influenza. (15) The greatest benefits were seen when people supplemented with small daily doses (800 IU or less) before the onset of symptoms.

During times when you aren’t getting much sunlight, you may want to consider a daily vitamin D supplement. Many factors influence how much vitamin D you need, so talk to your doctor to determine the right amount. (16) Most people do best with a supplement that contains 600-800 IU/day.

#7: Zinc

Zinc is a mineral often touted for its immune-boosting properties. (14) You’ll find zinc in cold lozenges and supplements designed to keep you healthy during the winter months. The reason zinc is essential for immune health is that it plays a central role in cellular function and development.

In multiple human studies, researchers have found daily zinc supplementation to boost the immune response of healthy elderly adults. This beneficial impact of zinc may be due to low dietary zinc intake in the elderly and declining zinc plasma concentrations as we age.

Final Thoughts

How we live and what we put inside of our bodies regulates the strength of our immune systems. When you eat a diet full of healthy whole foods, you give your body the building blocks it needs to thrive.

Several nutrients have proven incredibly beneficial for immune health. When you need extra immune support, consider adding in daily immune-boosting supplements and foods for protection.


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  1. Juszkiewicz A, et al. 2018. An attempt to introduce immunomodulatory effect in rowers with spirulina extract. Journal of the International Society of Sports Nutrition.


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