It’s natural for our immune systems to slow down as we age but, according to one study, eating yogurt every day might help speed things up again. The study, published in the journal, Nutrients, found that yogurt helped several markers of immune function in people over 60. For the study, researchers recruited 200 participants who were over 60 and had normal blood glucose levels and white blood cell numbers. The participants were asked to avoid probiotics for two weeks and then were divided into two groups. One group consumed 120 mL of dairy yogurt containing Lactobacillus paracasei,Bifidobacterium lactis, and heat-treated Lactobacillus plantarum, daily for twelve weeks; the other group consumed 120 mL of milk, daily for twelve weeks. At the beginning and end of the study, researchers measured six markers related to immune function and found that:
Three markers of immune function—natural killer cell activity, and blood levels of interleukin-12 and immunoglobulin G1—increased significantly in those consuming yogurt, while those consuming milk experienced no significant changes in markers of immune function.
Compared to the milk group, interferon-gamma levels and natural killer cell activity increased significantly more in the yogurt group.
If you’re over 60, this evidence suggests that eating probiotic-containing yogurt every day might help keep your immune system strong. This study also adds to the growing list of yogurt’s health benefits: previous research has associated yogurt with a reduced risk of hypertension, reduced belly fat, and less artery thickening, all of which could potentially reduce the risks of stroke and heart attack. However, it’s important to remember that yogurts vary in their probiotic, sugar, and fat content—not all varieties will contribute to your health. So, be sure to do your research and check nutrition and ingredient labels before you buy.