5 Immune-Boosting Supplements You’ve Probably Never Heard Of

Green bee propolis is a resin-like substance collected by bees from trees and plants, particularly in Brazil, where it is derived from the Baccharis Dracunculifolia plant. Propolis has been used in traditional medicine for centuries due to its antimicrobial and anti-inflammatory properties. Green bee propolis, in particular, contains a higher concentration of flavonoids (natural compounds with antioxidant properties), which may help to support the immune system by reducing oxidative stress.

While scientific research on its immune-boosting potential is still developing, some studies suggest that propolis may enhance the body’s natural defences by modulating immune cell activity. It is also traditionally believed to have antiviral properties, although more research is needed in this area.

Active hexose correlated compound (also known as AHCC) is a fermented extract derived from specific types of mushroom. It is particularly popular in Japan, where it is widely used as a dietary supplement to support immune function.

Preliminary studies suggest it may enhance the activity of natural killer (NK) cells, which play a crucial role in the body's defence against infections. Some research has also shown that it may help modulate the immune system and increase the production of cytokines (proteins that regulate immune responses). Though its mechanisms are still being studied, AHCC is considered a promising supplement for those looking to support their immune health.

Quercetin is a naturally occurring flavonoid found in many fruits and vegetables, including apples, onions, and berries. However, its potential as an immune-boosting supplement has only recently gained attention. Quercetin is known for its antioxidant and anti-inflammatory effects, which are important for maintaining a balanced immune response.

Some studies suggest that quercetin may help modulate the immune system by supporting the function of various immune cells, including T-cells and macrophages. Additionally, quercetin is often highlighted for its role in improving the bioavailability (absorption and utilisation) of other immune-boosting nutrients, such as zinc.

Despite its striking name, tiger milk is a mushroom (Lignosus rhinocerus) which has been used in traditional Southeast Asian medicine for centuries. It is named after a legend suggesting it grows from the milk of a tigress. This rare mushroom is valued for its ability to support respiratory health, which is closely linked to immune function. Modern research into tiger milk mushroom is still in its early stages, but it has shown potential as a potent immunomodulator, meaning it may help regulate the immune response. This makes it an intriguing supplement for supporting overall immune resilience, especially in relation to respiratory wellness.

Lactobacillus reuteri is a probiotic strain found naturally in the human gastrointestinal tract. Unlike many probiotics, which primarily support digestive health, Lactobacillus reuteri has been linked to broader immune benefits. Some research suggests that this strain may help to maintain a healthy balance of gut bacteria, which is essential for a well-functioning immune system, as around 70% of the immune system resides in the gut. Additionally, Lactobacillus reuteri is thought to stimulate the production of antimicrobial peptides, which help defend against harmful pathogens.