What I am doing to delay ageing (part III): spermidine

and how to increase our intake and its bodily production

Spermidine, a compound ubiquitous in sperm, is central to regulating cell growth and genetic expression. A positively charged molecule, it binds to negatively charged DNA - matching with the grooves of the helix as a jigsaw piece does with the aggregate picture. Inducing autophagy, it can also play a key role in delaying the ageing process. In mice, its consumption can prevent liver disease and relieve cancer cell defects, thereby contributing to a substantial boost in lifespan. In rats, as well as reduced brain inflammation (therefore likely lower incidence of neurodegenerative diseases), it even reduces anxiety!

Endogenous production of spermidine occurs via our cells and our microbiomes. Exogenous accumulation via our dietary consumption habits is also possible. Our endogenous production declines as we age, and in laboratory experiments of model organisms, increasing exogenous intake increases longevity. Spermidine levels are also comparatively higher in nonagenarians and centenarians, and dietary intake is correlated with reduced blood pressure and less heart disease. Hence, we have another promising target to promote a long and healthy life.

In a typical US diet, corn yields the highest levels per serving, yet green peas contribute the greatest amount on average. Mushrooms are also high in spermidine content, as are soybeans and teas. In general, it appears that vegetable intake is a good proxy for spermidine intake. Apples, pears, and mangoes are also rich in spermidine. For meats, offals outperform the rest. For dairy, mature cheese connoisseurs have struck the jackpot! Red wine tasters are also fortunate in this respect.

However, we must not neglect our microbiomes. Bifidobacterium, as well as reducing inflammation, is associated with endogenous spermidine production. Our internal bacteria are fibre-feeding, which suggests we should increase our intake of legumes and wholegrains. In general, a recurring theme in this series will be the promotion of whole foods over the (ultra) processed garbage we typically eat. I cut out most processed foods from my diet long ago, and it certainly does not just promote taste…