Human studies have not shown longer life, and one found no memory benefit after 12 months. The guide reviews Spermidine evidence from animal studies and human trials. It separates promising animal findings from mixed results in people. In animals, this compound helps cells clear out worn parts. That cleanup process is called autophagy. Giving it to animals has also extended lifespan. Those findings do not establish the same benefit in humans. One 2024 human study tested a supplement dose of 40 mg daily. It found little change in blood levels of spermidine and related compounds. That raises questions about how well supplements reach the blood. It does not, by itself, settle whether they affect health or lifespan. The excerpt gives no age range or study size for that trial. Food intake offers another piece of context. A 2026 study included 192 older Danish adults with heart artery disease. Their middle daily intake from food was 11.5 mg. Sources include wheat germ, aged cheese, mushrooms, peas, and lentils. This was not proof that food works better than supplements. For BioSocial members, a dose is not the same as a result. A useful shared record could include daily dose, food sources, and start date. Bloodwork dates and other routine changes add context when comparing your numbers. Community notes can reveal patterns worth exploring, but cannot prove longer life. Keeping expectations separate from measured changes makes those conversations more useful. If you track this habit, what dose, timeline, and changes—or lack of changes—have you recorded?