Want to support your immune system? Australia has plenty of science-backed supplements, and many are regulated by the Therapeutic Goods Administration (TGA).

Below are 10 top immune boosters, each with its own benefits. All are part of the Mr Vitamins Immune Booster collection.

Not every immune supplement is a listed medicine. Some, like elderberry syrups or mushroom powders, are regulated as foods instead. Where a product is TGA-listed, you'll see an AUST L, AUST R, or AUST L(A) number on the label, so check the pack yourself.

Reviewed on 08/09/26 · Next review: September 2027.

Top 10 Supplements for Immune Support

1. Vitamin C
2. Vitamin D
3. Zinc
4. Probiotics
5. Elderberry
6. Echinacea
7. Aged Garlic Extract
8. Olive Leaf Extract
9. Medicinal Mushrooms
10. Manuka Honey
    

Top 10 Natural Immune Support Supplements Summary

1. Vitamin C

Vitamin C is a powerful antioxidant and one of the most popular immune supplements. Your body can't make it, so you need to get it from food or supplements. A review in Nutrients Journal found these key benefits:

Supports immune cell function

Vitamin C builds up in immune cells and helps them move toward and destroy germs. It also helps clear out old immune cells to protect your tissues during infection.

Strengthens overall immune defence

Vitamin C supports both your fast-acting and longer-term immunity. A deficiency weakens your immune system and makes infections more likely.

Reduces risk and severity of illness

Getting 100-200 mg of vitamin C daily may lower your chances of getting sick. If you do catch a cold, it can help you recover faster.

Vitamin C comes as capsules, chewables, and powders in Australia, and some are non-acidic for gentler digestion. A daily dose, or a higher dose at the first sign of a cold, can safely support your immune system.

Shop Designs For Health Liposomal Vitamin C

2. Vitamin D

Vitamin D is known as the "sunshine vitamin," and it plays a big part in keeping your immune system balanced. It's known for bone support too, but it also controls how immune cells work. Many Australians don't get enough, especially in winter, due to indoor lifestyles. Studies show vitamin D can:

Regulate the immune system

Immune cells have special receptors for vitamin D and can activate it right where it's needed. This helps your immune cells communicate and coordinate better during an infection.

Lower risk of infection

There's a strong link between low vitamin D and a higher risk of infection. People who don't get enough are more likely to catch colds and flu.

Maintain immune defence readiness

Clinical studies show enough vitamin D may help protect against respiratory infections. Keeping your levels healthy helps your immune system fight off germs.

Health experts recommend vitamin D3 supplements, especially in colder months, available as capsules, drops, or sprays. It's one of the best basic immune health support supplements you can take, since it helps immune cells work and keeps inflammation in check.

Shop Micronutrition Vitamin D3

3. Zinc

Zinc is an important mineral for a healthy immune system. It helps immune cells grow and work, including neutrophils, natural killer cells, and T-lymphocytes. Even a small zinc deficiency can make it harder for your body to fight infection. Research has found these links between zinc and immunity:

Supports immune cell function

Zinc is essential for hundreds of immune cell functions. Studies show zinc supplements, especially for older adults or people with low levels, can reduce infection risk and inflammation.

Protects skin and inner barriers

Zinc helps keep your skin and mucosal linings strong, which are your body's first line of defence. It also works as an antioxidant, protecting your cells from damage.

Zinc deficiency weakens immunity

Without enough zinc, your immune system doesn't work as well, and you're more likely to get sick. Zinc gluconate lozenges taken at the first sign of a cold may shorten the illness.

Zinc citrate or gluconate tablets are common in Australia, and you don't need a high daily amount to see a benefit. Just don't take high doses of zinc for a long time, since it can affect your copper levels.

Shop Herbs Of Gold Ultra Zinc+

4. Probiotics

Probiotics are "friendly" bacteria that keep your gut healthy, and about 70% of your immune cells live there. Taking probiotics helps balance your gut microbiome, which in turn trains and balances your immune system.

Study reviews of probiotics and immunity have shown:

Probiotics strengthen immune responses

Certain strains, like Lactobacillus and Bifidobacterium, help your immune system respond properly to germs without overreacting. They also strengthen your gut barrier, keeping unwanted microbes out of your bloodstream.

Fewer colds and shorter illnesses

A Cochrane review of trials found daily probiotic use led to fewer respiratory infections. When illness did occur, it was usually shorter and milder.

Look for strains like Lactobacillus rhamnosus GG or Bifidobacterium lactis Bl-04. They come in high-dose capsules or powders (30-50 billion CFU) to support a healthy gut and immune system.

Shop Activated Probiotics Biome Daily

5. Elderberry

Elderberry usually means black elderberry (Sambucus nigra), a popular herbal remedy for colds and flu. The berries are packed with flavonoids called anthocyanins, which may help fight viruses and reduce inflammation. It has a long history of traditional use in Europe, and modern science is starting to back it up.

Studies have found these links between elderberry and immunity:

Anti-viral action

Elderberry contains compounds that block viruses from entering cells. It also boosts immune signals called cytokines, helping immune cells find and attack infected cells.

Speeds up immune responses

Lab studies show elderberry extract interferes with viral proteins and boosts cytokine production. This helps your immune system respond faster and clear infections early.

Clinical evidence of symptom relief

A meta-analysis of randomised trials found elderberry substantially reduces the duration of upper respiratory symptoms compared to placebo, with the strongest effect seen for flu.

Elderberry comes as syrups, lozenges, gummies, liquid extracts, and capsules, and kids tend to like the taste. It's best used at the first sign of a cold or flu, not as a long-term daily preventative.

Shop Eagle Elderberry Viral Protect

6. Echinacea

Echinacea is an immune system "modulator." It can boost your immune system when you have a cold, and it can help calm an overactive immune system in autoimmune conditions. People take it to prevent colds and flu or ease symptoms early. Indigenous North Americans have used it for centuries, and it's now popular worldwide.

Research shows echinacea supports the immune system by:

Regulating the immune system

Echinacea boosts the number and activity of immune cells like macrophages and natural killer cells. It also helps release cytokines that boost your immune response early on, helping you avoid getting sick or recover faster.

Fewer and shorter colds

A large meta-analysis in The Lancet Infectious Diseases found echinacea lowers the risk of getting a cold by 58%. If a cold did happen, it lasted 1.4 days less on average.

Decreases illness severity and complications

Studies also link echinacea to fewer complications and less severe illness. This can lower the need for antibiotics.

In Australia, echinacea comes as capsules, tinctures, and blends with herbs like garlic or elderberry. Throat sprays deliver it right to your respiratory lining, so it's a handy remedy if you catch colds often.

Shop Natures Sunshine Ultimate Echinacea

7. Garlic (Aged Garlic Extract)

Garlic is a common cooking ingredient, but it's also a well-known immune-boosting plant. Allicin and other sulphur compounds in fresh garlic help fight germs, and garlic is a popular home remedy for colds. Aged garlic extract concentrates its beneficial compounds and lowers the harsh sulphur smell, so it's easier on your stomach.

Here are some proven benefits of garlic for your immune system:

Improving immune cells

A trial by UF Food Science and Human Nutrition found healthy adults taking aged garlic had far more active natural killer (NK) cells and T cells. These cells attack virus-infected cells and cancer cells to protect your body.

Fewer and milder colds and flu

Garlic compounds fight germs and work as antioxidants too. After 45 days on a garlic supplement, one study found the garlic group had fewer and milder colds and flu than the placebo group.

In Australia, odourless aged garlic extract capsules like Kyolic® give you the benefits without the garlic breath. Regular garlic capsules or fresh garlic in your diet help too, but aged extract has the most research behind it.

Shop Nutralife Kyolic Aged Garlic Extract

8. Olive Leaf Extract

Olive leaf extract comes from the leaves of the olive tree (Olea europaea). The Mediterranean region has valued it for health for a long time. The leaf contains oleuropein and other polyphenols, which fight inflammation, bacteria, and free radicals. It's becoming a popular immune booster, often used to support the immune system generally or to help shorten colds.

Here's how olive leaf extract supports the immune system:

Antioxidant and anti-inflammatory support

Olive leaf is rich in antioxidants that protect your immune cells from damage during infection. It also reduces excess inflammation, which can ease symptoms like a sore throat or stuffy nose.

Less time spent sick

Human research on olive leaf and immunity is still developing, but one clinical trial in high school athletes found it reduced sick days by about 28%. It didn't reduce the number of colds caught, just how long they lasted.

In Australia, olive leaf extract is available as capsules, tablets, or tinctures. Choose one with a standardised oleuropein percentage so you know you're getting the right dose.

Shop Comvita Olive Leaf Extract

9. Medicinal Mushrooms (Reishi & Others)

Eastern medicine has used medicinal mushrooms for hundreds of years to support health and immunity. They've become more popular in the West recently too. Types like Reishi (Ganoderma lucidum), Shiitake, Maitake, Chaga, and Cordyceps have compounds called beta-glucans and triterpenes that strongly affect the immune system. These mushrooms can boost a weak immune system or calm an overactive one, helping keep things balanced.

Medicinal mushrooms support the immune system by:

Broad immune support

Reishi and similar mushrooms improve both your fast-acting and learned immune responses. They boost macrophages, dendritic cells, and T and B cells, and help produce cytokines that coordinate your immune response.

Stress and immunity

Many medicinal mushrooms are also adaptogens, meaning they help your body handle stress. Since stress can weaken immunity, this is another way mushrooms may help. One study found Reishi supplements increased T-cells and improved immune function in healthy adults.

Medicinal mushrooms come as capsules or powders you can add to smoothies, coffee, or broth. Many products blend Reishi, Shiitake, Maitake, Cordyceps, and Turkey Tail together for combined benefits.

Shop Metagenics Super Mushroom Complex

10. Manuka Honey

Manuka honey comes from bees that pollinate the Manuka bush (Leptospermum species), found in Australia and New Zealand. It's known worldwide for its antimicrobial properties. Manuka honey helps your immune system in two ways: it fights germs directly, and it soothes your throat and lungs. Here's how:

Natural antibacterial power

Manuka honey is often called "nature's antibiotic" for its broad antibacterial power. Studies show it works against many bacteria, thanks to a high level of a compound called MGO.

Kills bacteria and viruses

Manuka honey helps clear bacteria, making it easier for your immune system to fight infection. It works against bacteria, viruses, and some fungi, so it can help with different types of infections.

Antioxidant and soothing effects

A spoonful can soothe a cough or sore throat, and studies show it may work as well as common cough syrups for children. It coats the throat and contains antioxidants that calm irritated tissue.

Manuka honey is rated by its methylglyoxal (MGO) level. The higher the rating, the more potent the honey.

MGO Rating: What You Need to Know

MGO is short for methylglyoxal, a compound found in all honey. Manuka honey just has much more of it.

The MGO rating shows how much MGO is in the honey, measured in milligrams per kilogram. A higher number means a more potent honey.

For a milder, everyday option, try MGO 100+ or MGO 250+. For a stronger antibacterial option, look for MGO 400+ or MGO 550+.

For general immune support, look for at least MGO 10+. Take a spoonful daily, mix it into warm water or tea, or dab it on a sore throat.

Shop Manuka Health MGO 400+

Safety and Who Should Be Careful

Most of these supplements are well tolerated, but a few need extra care depending on your situation.

• Echinacea and autoimmune conditions. Echinacea stimulates immune activity, so check with your doctor first if you have an autoimmune condition or take immune-suppressing medication.
• High-dose, long-term zinc. Taking high doses of zinc for a long time can lower your copper levels. Stick to the label directions rather than using high doses long-term.
• Raw elderberries. Raw or unripe elderberries can cause nausea, so only use properly prepared commercial products, not berries picked at home.
• Olive leaf and blood pressure medication. Olive leaf may mildly lower blood pressure, so check with your doctor if you take blood pressure medication.
• Medicinal mushrooms and blood thinners. Some mushrooms, including Reishi, may affect blood clotting. Speak with your doctor first if you take blood thinners or have surgery planned.
• Honey and infants. Never give honey, including Manuka honey, to a baby under 12 months old.
• Pregnancy and breastfeeding. Several herbs here, including echinacea and elderberry, have limited safety data in pregnancy, so check with your doctor or midwife first.

Frequently Asked Questions

Conclusion

Adding any of these top 10 supplements to your routine can help keep your immune system strong. Each one, whether a vitamin, mineral, herb, or extract, supports immunity in its own way.

Many people find that combining a daily nutrient like vitamin D or C with a herbal remedy at the first sign of illness works best. Always choose quality supplements and take the right dose.

Supplements work best alongside good habits: sleep, a balanced diet, exercise, and stress management. With the right support, your immune system can protect you better, even when others around you are getting sick.

References

Carr AC and Maggini S. (2017). Vitamin C and immune function. Nutrients, 9(11):1211. PMID: 29099763.

Aranow C. (2011). Vitamin D and the immune system. J Investig Med, 59(6):881-6. PMID: 21527855.

Gombart AF, Pierre A, Maggini S. (2020). A review of micronutrients and the immune system, working in harmony to reduce the risk of infection. Nutrients, 12(1):236. PMID: 31963293.

Zhao Y, Dong BR, Hao Q. (2022). Probiotics for preventing acute upper respiratory tract infections. Cochrane Database Syst Rev, 8:CD006895. PMID: 36001877.

Hawkins J et al. (2019). Black elderberry (Sambucus nigra) supplementation effectively treats upper respiratory symptoms: a meta-analysis of randomized, controlled clinical trials. Complement Ther Med, 42:361-365. PMID: 30670267.

Shah SA et al. (2007). Evaluation of echinacea for the prevention and treatment of the common cold: a meta-analysis. Lancet Infect Dis, 7(7):473-480. PMID: 17597571.

Percival SS. (2016). Aged garlic extract modifies human immunity. J Nutr, 146(2):433S-436S. PMID: 26764332.

Somerville V et al. (2019). Effect of olive leaf extract on upper respiratory illness in high school athletes: a randomised control trial. Nutrients, 11(2):358. PMID: 30744092.

Lin Z and Wang X. (2019). Immunomodulating effect of Ganoderma (Lingzhi) and possible mechanism. Adv Exp Med Biol, 1182:1-37. PMID: 31777013.

Johnston M et al. (2018). Antibacterial activity of Manuka honey and its components: an overview. AIMS Microbiol, 4(4):655-664. PMC6613335.