There are two main ways for obtaining bulk spermidine, one is from natural

foods, the other is from chemical synthesis. There are several foods high in

spermidine, such as wheat germ extract, fruits, grapefruit, yeast, mushrooms,

meat, soybeans, cheese, Japanese Natto (fermented soybeans), green peas,

rice bran, cheddar, etc. That’s why the Mediterranean diet is so popular since

a high polyamine content in it. Below is the amount of spermidine content in

foods from Wikipedia: According to the literature, wheat germ is the best food

that has the highest spermidine.