Boost your immune system with Mangosteen and Shiitake

Mangosteen and Shiitake: a fruit and a mushroom that can help boost the body's immune system.

Immune system

The immune system is complex and performs important functions, but we can simplify it by focusing on the three main functions:

• protects the body from pathogens (external invaders that cause disease),
• removes damaged cells and tissue,
• recognises and removes abnormal cells, such as cancer cells.

It is made up of several factors whose sole purpose is to keep the body healthy. It is therefore very important that the immune defences are always high. 

A balanced lifestyle including a healthy and varied diet, physical activity and an adequate number of hours of restful sleep are the first prerequisites for a strong immune system. In particular, many indispensable nutrients (vitamins, minerals, antioxidants), which we take in through food, support the normal function of the immune system. In this article we take a closer look at two foods, a fruit and a mushroom, that have really interesting properties and are suitable for supporting our immune system when extra support is needed.

Mangosteen

Mangosteen is considered a 'super fruit'. It is the fruit of the tropical plant Garcinia mangostana and is native to some islands in South East Asia.
This particular exotic fruit provides numerous health benefits and is an important source of active ingredients with various 'healing' virtues: the flesh and pericarp of the mangosteen, rich in polyphenolic compounds called xanthones, have anti-inflammatory activity that can block the synthesis of prostaglandins, which are the main mediators of inflammation.
α-mangostin appears to be the most active xanthone present. In addition to being an anti-inflammatory, it is also a powerful antioxidant, which has a strong anti-free radical action. Mangosteen also contains a good amount of Vitamin C, B vitamins (especially folic acid), which are also indispensable for the body's natural defences. Finally, it contains fibre and minerals such as Copper, Manganese, Magnesium and a good amount of Calcium and Potassium.

A randomised double-blind placebo-controlled clinical trial (1) involved 59 subjects. The mangosteen-treated group was given a mangosteen product containing vitamins and minerals for 30 days. At the end of the treatment, it was found that mangosteen intake had resulted in increased levels of T-helper cells (involved in the immune response) and decreased levels of C-reactive protein (a protein that is produced in the acute phase of inflammation), and in general, the mangosteen-treated group reported better overall health.

Shiitake mushroom

From Traditional Chinese Medicine we have the now well-known Shiitake mushroom (Lentinula edodes). In 1500s China, Shiitake was already well known, both as a food and as a phytotherapeutic remedy. It was used as a panacea and to increase vital energy. Over the centuries it has been used to improve symptoms of flu, fever, bronchitis, allergies.
Also increasingly common in our diet, especially in macrobiotics, as a fresh or dried food, this mushroom has several beneficial properties.

The shiitake mushroom contains essential amino acids, fibre and unsaturated fats, and is an excellent source of provitamin D (ergosterol), which becomes calciferol (vitamin D) in the presence of ultraviolet light. It also contains B vitamins and various minerals.
Its main property is undoubtedly its immunostimulating capacity, which is mainly due to the polysaccharide component present. A number of these compounds have been isolated, and one in particular, lentinan (a β-glucan), has proved particularly active.

In a randomised double-blind placebo-controlled clinical trial (2) 42 subjects were involved. Following the intake of Lentinex (Shiitake extract containing lentin) for 6 weeks, a significant increase in the levels of B lymphocytes, cells responsible for producing antibodies against a specific antigen, was observed.

Bibliographic references

1. Tang, Y.P.; Li, P.G.; Kondo, M.; Ji, H.P.; Kou, Y.; Ou, B. Effect of a mangosteen dietary supplement on human immune function: A randomized, double-blind, placebo-controlled trial. J. Med. Food 2009, 12, 755–763, PubMed.
2. Gaullier, J.M.; Sleboda, J.; Øfjord, E.S.; Ulvestad, E.; Nurminiemi, M.; Moe, C.; Tor, A.; Gudmundsen, O. -  Supplementation with a soluble-glucan exported from Shiitake medicinal mushroom, Lentinus edodes (Berk.) msinger mycelium: A crossover, placebo-controlled study in healthy elderly. Int. J. Med. Mushrooms 2011, 13,319–326, PubMed.