For this study, researchers wanted to investigate how vitamin D3 levels affect the body’s inflammatory response and how that response translates into allergies and asthma.

To do this, they observed both children and adults, had them increase their vitamin D intake, and then assessed the participant’s cellular inflammatory response as well as any subsequent symptoms.

Sure enough, when participants increased their vitamin D levels, they experienced fewer symptoms and less severe asthma overall. Additionally, the study authors noted, some cells showed that higher levels of vitamin D translated into more blimp-1 (a protein that promotes a healthy T-helper immune response).

And of course, for qualitative research, one of the study’s co-authors repeated the study in mice and saw similar results. In fact, mice with increased levels of vitamin D even showed fewer allergy-causing antibodies that can exacerbate hay fever and eczema.

As the study authors write in their study, their results indicate that “vitamin D3 shifts pro-inflammatory to anti-inflammatory immune responses.”