The US FDA has not ruled on a safe upper limit for food-derived spermidine, but the European Union's European Food Safety Authority has deemed 6mg of supplemental food-derived spermidine to be the safe upper limit.

To date, most studies have been conducted using a daily dose of 1mg of food-derived spermidine, together with spermine and putrescine. 

Synthetic spermidine has not been tested for safety in humans.

While we can’t speak directly about the formulation of other spermidine products, here are some of the main differentiators of Primeadine®/Oxford Healthspan.

• We source our raw materials from Japan, which is known for their Nobel Prize winning scientific leadership on autophagy, or cell renewal. They have the most advanced extraction process, are known worldwide for their rigorous quality control and testing, and they meet the standards of the Japan Health Food and Nutrition Food Association. Our raw materials are manufactured in Japan in an FDA-registered and -inspected facility with ISO22000 standards, the highest in food quality control. Our raw materials are tested for heavy metals, mold, fungi and bacteria at the Japan Food Research Lab (JFRL), a third party independent testing lab. Every single batch must be tested here as food-derived spermidine will have varying quantities of spermidine per batch and we must ensure that every batch contains the minimum effective dose of 1mg stated on our labels. In addition, our spermidine is encapsulated in an FDA cGMP facility in the USA and undergoes purity testing there as well at Eurofins or Delta.
• Our capsules do not contain any synthetic ingredients, whereas other supplements contain magnesium stearate (of which circa 80% will contain hydrogenated fats; the supplement industry is not legally required to get rid of hydrogenated oils the way the processed food industry has been mandated by law to), shellac, talc and glycerin. Our products are all suitable for vegans.
• Our formulation contains a special type of prebiotic fiber, called FructoOligoSaccharide (FOS), that selectively feeds the friendly spermidine-producing bacteria in the gut biome. The idea is to increase both supplemental or 'exogenous' spermidine as well as encourage your own body's natural ability to produce 'endogenous' spermidine.
• We do not use liposomes in Primeadine because this is unnecessary for absorption and would prevent the benefits that happen when spermidine is exposed directly to the gut lining. There is no evidence that spermidine cannot be taken up by the cells on its own. Similar to amino acids, polyamines do not need a liposome to cross into the cell or to be taken up with epithelial cells. The process of creating a liposomal version also creates unnecessary expense.
• We do not synthetically enrich our product with synthetic spermidine.
• We do not use doses beyond what the European Food Safety Authority (EFSA) has mandated as safe for human consumption, which is 6mg daily. Please note that this is related to food-derived spermidine. Synthetic spermidine and synthetically enriched spermidine have never been tested in humans for safety or efficacy and are being sold without regulatory oversight. 
• We work closely with our scientific and clinical advisers at the University of Oxford, all of whom take our product and share it with their families. We are also the only non-Japanese member of the Japan Autophagy Consortium, whose Senior Adviser is the 2016 Nobel Prize Winner in Medicine or Physiology, Prof Yoshimori Ohsumi, and whose Director is Prof Tamotsu Yoshimori, Osaka University. Prof Yoshimori conducted all of the mammalian research in autophagy that helped underpin Prof Ohsumi's work in yeast cells. 

Synthetic spermidine is a 2-dimensional chemical mimic, but we should never forget that molecules are 3-dimensional. Humans have co-evolved with plants over millenia and our bodies recognize the 3-dimensional molecules made by plants. Our bodies can recognize some elements of 2-dimensional mimics, but they are akin to the mirror images of your hands when you put your palms together - 2-dimensionally identical, and yet your right hand cannot wear a left-handed glove. 

We have tested other spermidine products whose labels state they contain 'wheat germ with spermidine' and noticed that they have a small amount of wheat germ 'cut in' with high amounts of synthetic spermidine. Often, these are high dose, low cost options with no guarantee that they will work, or that they are safe. Synthetic spermidine has not been tested for safety or efficacy in humans, only food-derived spermidine has. 

Epidemiological studies have correlated higher spermidine levels with longer life. This is because spermidine induces autophagy, the body’s cellular renewal and "clean up" process, and it inhibits 9 of the 12 hallmarks of aging, the paths down which we age. Some of the hallmarks spermidine acts upon include inflammation, stem cell and mitochondrial dysfunction, and gut dysbiosis.

Hacking the hallmarks and inducing autophagy have a whole-body effect and are responsible for the many benefits experienced.

Supplementation with food-derived spermidine in humans has been shown to support cognition and heart health, promote hormonal balance, improve hair growth and fullness (including eyelashes and brows), and strengthen nails.

Other benefits, as noticed by our clients, include deeper, sounder sleep, hair color repigmentation, enhanced energy levels, brighter, more supple skin, and improved gut health.

We take great care to use the highest quality ingredients and to keep out the 'nasties' commonly used in the supplement manufacturing process in our products. We take the same approach that we do when baking a birthday cake for our children: we use the highest quality ingredients - no industrial seed oils such as wheat germ oil that oxidizes rapidly, no magnesium stearate to make the powder flow faster through automated encapsulation equipment (approximately 70% of all magnesium stearate used as 'flow agents' are hydrogenated industrial seed oils), no talc to make the powder denser to fit more compactly into fewer capsules. 

We also do not use synthetic spermidine which is very cheap and often 'cut' into products stating 'wheat germ with spermidine.'  

We choose food-derived spermidine. Yes, it is more costly, just as the best cake ingredients for your child's birthday cake would be too. It's a choice and philosophy about value for money. 

Primeadine® works at a cellular level, so the results take time (we recommend taking it continously for 12 weeks for best results). That said, some of our customers have reported deeper sleep, as measured by the sleep-tracking ōura ring, from the very first night of taking it. See our Testimonials section for more!