Oyster mushrooms – Latin name: Pleurotus ostreatus – contain sugar chains that activate the immune system, and help to prevent flu and colds. A sponsored study suggests that athletes can reduce their chances of becoming ill by taking a supplement that contains oyster-mushroom extract.
Oyster mushrooms – Latin name: Pleurotus ostreatus – contain sugar chains that activate the immune system, and help to prevent flu and colds. A sponsored study suggests that athletes can reduce their chances of becoming ill by taking a supplement that contains oyster-mushroom extract.
Moderately intensive exercise stimulates the immune system, and reduces the chances of you getting a cold or flu; highly intensive exercise is more likely to overload the immune system – and therefore increases the chance of upper respiratory tract infections.
The figure below is taken from a review article by David Nieman in 1994 [Int J Sports Med. 1994 Oct;15 Suppl 3:S131-41.], and shows the relationship between exercise and the effectiveness of the immune system. It makes clear why endurance sports take a heavy toll on the immune system.
Marathon runners, triathletes and cyclists who want to avoid becoming ill – but want to continue training – can choose between two basic dietary strategies, according to a review published by Austrian nutritionists in Nutrients in 2012 [Nutrients. 2012 Sep;4(9):1187-212.].
According to the Austrians endurance athletes’ first priority is to make sure that they have a balanced diet Secondly, they should consume part of their daily carbohydrate allowance – the review says six percent – during while doing their training.
So far there is insufficient scientific evidence to back up other immunomodulatory strategies, such as increasing intake of protein, BCAAs or supplementation in the form of a combination of L-cystine and L-theanine, say the Austrians.
The review does not cover phytochemicals, and therefore not pleuran either. Pleuran is an extract from oyster mushroom Pleurotus ostreatus that contains glucan. The structural formula of pleuran is shown here.
Pleuran is also the name of a Slovakian manufacturer of imunoglukan supplements. Pleuran funded a study, published in 2011 in the European Journal of Applied Physiology, in which researchers gave the Pleurotus-ostreatus extract to 25 elite athletes. [Eur J Appl Physiol. 2011 Sep;111(9):2033-40.] An equal-sized group of athletes were given a supplement containing no active ingredients for the same period of three months.
The athletes in the experimental group took two capsules of Pleurotus ostreatus extract before breakfast every day. The capsules contained 200 mg pleuran.
Before and after the supplementation period the researchers asked the athletes about whether they had been bothered by a runny nose, sore throat, cough, fatigue, headache and other symptoms that would indicate a viral infection. Each athlete was assigned a score on the basis of the answers given. The figure was significantly lower in the experimental group at the end of the supplementation period than it had been at the start.
Supplementation with the glucans in Pleurotus ostratus boosted the Natural Killer cell count in the blood. Natural Killer cells are the immune cells that spring into action first when a virus or other pathogen tries to enter your body.
Immunologists think that our immune system regards glucans and other compounds in fungi [a mushroom is a form of fungus] as a piece of membrane from a bacteria or virus, and therefore goes on high alert.
“The results from this double-blind study suggest that pleuran, insoluble beta-glucan from the Pleurotus ostreatus mushroom, supplementation may have the capacity to attenuate immune changes and decrease URTI symptoms in intensively training athletes”, the researchers conclude.
Pleuran (?-glucan from Pleurotus ostreatus) supplementation, cellular immune response and respiratory tract infections in athletes.
Bergendiova K, Tibenska E, Majtan J.
Source
Pneumo-Alergo Centrum, s.r.o., Uzbecka 16, 821 06, Bratislava, Slovakia.
Abstract
Prolonged and exhausting physical activity causes numerous changes in immunity and sometimes transient increases the risk of upper respiratory tract infections (URTIs). Nutritional supplements as countermeasures to exercise-induced changes have increasingly been studied in the last decade. One of the most promising nutritional supplements is ?-glucan, a well-known immunomodulator with positive effects on the function of immunocompetent cells. In this double blind, placebo-controlled study, we investigated the effect of pleuran, an insoluble ?-(1,3/1,6) glucan from mushroom Pleurotus ostreatus, on selected cellular immune responses and incidence of URTI symptoms in athletes. Fifty athletes were randomized to pleuran or placebo group, taking pleuran (commercial name Imunoglukan(®)) or placebo supplements during 3 months. Venous whole blood was collected before and after 3 months of supplementation and additionally 3 months after supplementation period was completed. Incidence of URTI symptoms together with characterization of changes in phagocytosis and natural killer (NK) cell count was monitored during the study. We found that pleuran significantly reduced the incidence of URTI symptoms and increased the number of circulating NK cells. In addition, the phagocytosis process remained stable in pleuran group during the study in contrast to placebo group where significant reduction of phagocytosis was observed. These findings indicate that pleuran may serve as an effective nutritional supplement for athletes under heavy physical training. Additional research is needed to determine the mechanisms of pleuran function.
PMID: 21249381 [PubMed – indexed for MEDLINE]