Daily supplementation with Chlorella pyrenoidosa (SC) for four weeks before and two weeks after a two-day period of intensive training increased the resting concentration of immunoglobulin A (IgA).
This antibody plays a crucial role in the immune function of mucous membranes and may help explain why endurance athletes in particular have a higher than normal incidence of upper respiratory tract infection (URTI) or symptoms (URS).
Daily supplementation with SC was able to increase salivary sIgA concentration and secretion rate at rest. Together with previous research there is now substantial evidence to show that SC can enhance salivary sIgA;
“Our findings (in combination with those from previous research) do show some benefits from SC in terms of increases, above baseline levels, in salivary sIgA,” said Drs Corinna Chidley and Glen Davison, researchers from the Endurance Research Group at the University of Kent
“Resting sIgA concentration appeared to be increasing in the weeks after the intensified training period. It is possible therefore that more benefit would be evident with a longer supplementation period and it is feasible that this would also translate to a greater effect on URS reports.”
Chlorella in the nutra-algae space
Chlorella pyrenoidosa is a nutritional intervention popular in Japan that may act as a potential countermeasure in exercise-induced immunodepression.
However, there are relatively few studies on athletes and those with high physical activity levels.
Its benefits have not gone unnoticed by the nutra-algae space with Polish start-up Purella Food making available three product ranges containing its Korean-sourced chlorella including snack bars and Greendox fibre detox shakes.
The firm are also looking to develop a range of smoothies, sports bars and raw confectionary balls to bring the microalgae to the mainstream.
Meanwhile Swiss giants Bühler has heavily invested in R&D projects looking at insects, algae and pulses as alternative protein sources.
Last year, the company teamed up with the Federal Institute of Technology in Zurich (ETH Zurich) to develop cultivation, extraction and processing technologies for proteins that can be produced in a more sustainable way compared with meat and dairy products.
Drs Chidley and Davison took 26 subjects and asked them to provide resting saliva samples for determination of sIgA, at baseline (week zero) and following four, five and six weeks.
Throughout these weeks, subjects were given a daily supplementation with six grams a day (g/day) Chlorella (13 subjects) or placebo (13 subjects).
During week four a two-day intensified training period was undertaken with morning and afternoon sessions undertaken each day, respectively.
When the placebo (PLA) was compared to CP supplementation, baseline values were 54 micrograms per minute (µg/min) on average for the placebo group versus 57 µg/min for the test group.
However, by week four these values had increased to 54 vs 83 µg/min; by week five, 63 vs 98 µg/min and by week six, 58 vs 85 µg/min.
Minimal acute changes in sIgA were seen in response to individual exercise bouts, observed the team but was higher at some times in the Chlorella group (for bouts two and three).
Mechanism of action
The team thought the most likely mechanisms for salivary sIgA increases after 4–5 weeks of Chlorella supplementation were via the immunostimulating compounds found in chlorella such as polysaccharides and glycoproteins or protein/polysaccharides complexes.
However, they did acknowledge that chlorella does contain an abundance of nutrients, of which could influence immunity in athletes.
This, they added would require further study that included the determination of the bioavailability from orally consumed Chlorella and monitoring the levels of these substances in plasma and/or immune cells after ingestion.
Source: European Journal of Nutrition
Published online ahead of print: doi:10.1007/s00394-017-1525-9
“The effect of Chlorella pyrenoidosa supplementation on immune responses to 2 days of intensified training.”
Authors: Corinna Chidley, Glen Davison