Endurance Research Group

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A2 milk, asthma symptoms and performance

Effects of A2 milk on asthma symptoms, inflammation and exercise performance.

Summary

Asthma and exercise-induced bronchoconstriction (EIB) are more common in athletes than in the general population. it is possible that some dietary components are linked to asthma symptoms (via effects on the gut, immune system and inflammation). Some research has suggested that one of the proteins found in milk (A1 beta-casein) may contribute to this. Our research project aims to investigate whether A2 that naturally contains no A1 beta-caseins (i.e. A2 milk) can influence these markers in athletes with asthma or asthma-related conditions.

Find further information can be found on the trial registration site.

Objectives

Purpose:

To investigate the effect on airway health, inflammatory and immune markers, and exercise performance in athletes with asthma-related conditions who switch to using A2 milk from standard (regular) cow’s milk.

Hypothesis:

markers of airway health, inflammatory and immune markers, and exercise performance will be improved in the A2 milk arm, compared to the regular milk arm.

People

Professor John Dickinson, Principal investigator, School of Sport and Exercise Sciences, University of Kent.

Dr Glen Davison, Co-investigator, School of Sport and Exercise Sciences, University of Kent.

Will Gowers, PhD student, School of Sport and Exercise Sciences, University of Kent.

About

Asthma and exercise-induced bronchoconstriction (EIB) are obstructive airway diseases that may be caused (in part) by inflammation in the cells that line the small airways. They are more common in athletes than in the general population. Inflammation in the gut may influence inflammation in the small airways, which may impact on asthma severity. Regular cow’s milk contains a mix of A1 and A2 protein (beta-caseins). Previous research has shown that the A1 type of protein may affect gut transit and inflammation. It has also been shown to pass into the body and affect other organs e.g. skin and it is possible that regular cow’s milk (containing A1 protein) may be linked to EIB/asthma symptoms via this mechanism. Previous research has shown that when individuals switch to using milk containing only A2 protein (beta-caseins) gut transit and inflammation are improved. It is also possible that replacing regular cow’s milk with A2 milk may help to improve immune function and balance, which is another possible pathway linked to inflammation. The aim of this study is to find out whether switching to using milk that contains no A1 protein (A2 only) causes decreases in gut inflammation/damage, reduced airway inflammation and asthma symptoms, and improved immune function and exercise performance in active people with asthma.