A food compound in wheat germ and cheese boosted vaccine responses in older adults, but only some of them

A small pilot trial published in Aging Cell found that older adults whose immune systems had been under-responding to a third COVID-19 vaccine dose saw a meaningful antibody lift when given spermidine supplements alongside the booster. Spermidine is a naturally occurring compound found in wheat germ, mushrooms, parmesan, and cheddar, and the body also makes it; researchers think it works by supporting autophagy, the cellular cleanup process that declines with age and contributes to immunosenescence, the gradual loss of immune efficiency in older adults.

The study, led by Dr. Katja Simon at the Max Delbrück Center and Dr. Ghada Alsaleh at Oxford's NDORMS, focused on adults over 65 getting their third COVID shot. The lift was not uniform: the biggest gains in antibody levels and variant activity showed up in participants whose initial responses to vaccination had been weak, not in the over-65 average. That subgroup framing matters, because "over 65" obscures who actually benefited.

The trial is registered as NCT05421546 and tested a supplement dose, not dietary intake, so eating wheat germ or cheddar does not reproduce the effect. The work is COVID-vaccine specific and does not generalize to flu, RSV, or shingles boosters. Replication in larger, placebo-controlled cohorts is the next gate before any clinical use.