Spermidine occurs in all living cells as part of polyamine metabolism. Wheat germ provides the highest dietary concentration (~900 nmol/g), followed by soy products, aged cheeses, mushrooms, and legumes. A diet intentionally rich in these foods can provide 10–20 mg/day — within the range associated with mortality benefits in the Kiechl prospective study.

Can wheat germ alone replace supplements?

Yes — if consumed consistently. Two tablespoons of wheat germ daily provides ~2 mg spermidine, within the clinical trial range. Adding wheat germ to smoothies, yogurt, or oatmeal is a practical approach. Supplements offer convenience and precision.

Does cooking reduce spermidine in food?

Yes. Boiling reduces spermidine by 20–40% as it leaches into cooking water. Shorter cooking times, dry heat (roasting), and consuming wheat germ raw maximizes spermidine retention.