Spermidine is a naturally occurring polyamine compound found widely across all living organisms. This molecule participates in numerous cellular processes. It is produced within the body and obtained from external sources, particularly through diet.
The Body’s Own Production of Spermidine
The human body naturally synthesizes spermidine through a series of biochemical reactions, providing a continuous source for cellular functions. It forms from its precursor, putrescine, which originates from the amino acid ornithine. Commensal bacteria residing in the large intestine also contribute to spermidine synthesis. The levels of spermidine produced endogenously can decrease with age.
Dietary Sources of Spermidine
Spermidine is present in a wide array of foods, making dietary intake a significant avenue for obtaining this polyamine. Among the most concentrated sources is wheat germ, which can contain between 2 to 5 milligrams per 100 grams. Aged cheeses also offer substantial amounts, with concentrations ranging from 1.5 to 3 milligrams per 100 grams. The fermentation process involved in producing these cheeses enhances their polyamine content.
Mushrooms, including varieties like Black Shimeji and Shiitake, are notable sources, typically providing 0.5 to 1 milligram per 100 grams. Fresh mushrooms generally contain higher amounts compared to processed ones. Legumes and soy products are also rich in spermidine; soybeans can offer 1 to 2 milligrams per 100 grams. Fermented soybeans, such as natto, are particularly high. The Bacillus subtilis bacteria used in natto fermentation actively produce spermidine, further increasing its levels.
Whole grains, including amaranth, oats, and brown rice, contribute moderate amounts. Green peas, broccoli, cauliflower, pumpkin seeds, and certain fruits like durian and grapefruit also contain spermidine.
Spermidine in Supplemental Forms
Spermidine is also available in various dietary supplement formulations. Many of these supplements derive spermidine from natural sources, most commonly wheat germ extract. These natural-source supplements are typically standardized to ensure a consistent amount of spermidine per dose.
Alternatively, some supplements contain synthetic forms of spermidine, such as spermidine trihydrochloride. These laboratory-produced versions offer high purity and precise dosing. Spermidine supplements are available in various formats, including capsules, tablets, gummies, and liquid drops. Recommended daily doses generally range from 2 to 10 milligrams, though some products may provide up to 25 milligrams. Consulting a healthcare professional before incorporating any new supplement into one’s routine is advisable.