Science shows this supplement can really slow aging and experts are raving. But you can buy it NOW

It’s not exactly the most appealing name for a nutritional supplement, but it’s generating a lot of interest in the longevity world.

The protein, found in the body and in some foods, has shown promising results in tests on yeast, worms and mice, suggesting it can protect the heart and mind and even extend lifespan.

Human evidence is still in its infancy, but some enthusiasts claim it may have a wide range of benefits. It can boost fertility, improve sleep, stimulate gut health, make skin more supple, and increase energy levels.

What exactly is spermidine and why have so few people ever heard of it, if it really is the elixir of youth?

Spermidine was first discovered in human semen (hence the name), but is now found in cells throughout the body, in both men and women.

Its role lies in reducing inflammation and stimulating a process called autophagy (more on that later).

Two-thirds of the spermidine we need to function properly is produced by our bodies (mainly in the intestines). The rest comes from the food we eat.

However, as we age, our bodies no longer produce as much spermidine, which is why some scientists claim that increasing spermidine levels can slow the onset of aging and the health problems that come with it.

Central to that claim is the essential role spermidine plays in autophagy, a form of body cleansing that breaks down dead or diseased cells and reuses the parts as fuel or to create new healthy cells.

“Without autophagy, cells wouldn’t be able to develop or function properly,” says Katja Simon, a professor of immunology who leads a team studying autophagy at the Max Delbrück Center in Berlin. “Without autophagy, they would age faster.”

Autophagy is especially important in the mitochondria, the energy powerhouse of the cell.

As cells age, their mitochondria lose their ability to provide energy to cells and begin to self-destruct, resulting in a drop in our energy levels.

Spermidine combats this by activating autophagy in the mitochondria, causing them to undergo an internal refit and start functioning optimally again.

It also helps stem cells maintain their ability to divide and create new cells – a key factor in many of the health claims made for spermidine.

While most research to date has involved animal studies, Dr. Ghada Alsaleh, a researcher in immunology and autophagy at the University of Oxford, has conducted experiments using a spermidine supplement on human cells from patients who have received hip replacements.

The results (not yet published) show that the supplement induces autophagy in human tissue.

This discovery could be the first step toward an effective therapy for osteoarthritis, in which the protective cartilage surrounding a joint becomes inflamed and damaged, leading to pain and immobility.

The idea behind this is that spermidine can help repair and renew cartilage.

Sperm supplements are now becoming increasingly available on the high street and online, after studies showed they can lead to a fitter, longer life (although this is mainly through diet rather than supplements).

For example, people who ate higher amounts of spermidine-rich foods — such as whole wheat germ, vegetables (particularly shitake mushrooms, green peppers and broccoli) and aged cheese — were found to have a lower risk of premature death or heart disease and a longer lifespan, according to a 2018 study that followed 829 adults ages 45 to 84 for 20 years, reported in The American Journal of Clinical Nutrition.

Dr Olivia Lesslar, an Australian life extension physician, specializes in preventive health and psychoneuroimmunology (how the brain and immune system are connected). She says, “I prescribe spermidine to patients with diseases that are known to be partly due to autophagic dysfunction.

“These include kidney disease, inflammatory bowel disease, non-alcoholic fatty liver disease, diabetes, some cancers and neurodegenerative diseases,” she says.

‘People with fatigue report having more energy. Many also report thicker hair and stronger nails; even reversal of gray hair.

“I had a 41-year-old patient who felt it was one of the most important factors in helping him get pregnant, after trying for a few years.”

A 2023 study in the journal Nature Ageing found that spermidine boosted fertility in older female mice.

“I think spermidine has some interesting long-term health benefits,” adds Dr Tamsin Lewis, a psychiatrist and neuroscientist who runs a private lifespan research clinic in London.

“It doesn’t work on its own, but as part of an overall health strategy that includes diet, exercise, meditation and connection, I can see the benefits of a supplement when taken daily.”

Dietary sources and supplements are not the only way to increase spermidine levels.

A study published this month in the journal Nature Cell Biology found that calorie restriction and intermittent fasting also increased spermidine levels in humans.

Spermidine isn’t the only substance that can activate autophagy; several other supplements can as well, including resveratrol, quercetin, and alpha-lipoic acid.

The difference is that these other agents typically rely on a single pathway, while spermidine is considered superior because it induces autophagy through multiple mechanisms (for example, by blocking the action of a gene and enhancing other pathways involved in initiating and maintaining autophagy).

Research has also been done into other life-extending substances.

For example, a drug called rapamycin, originally used in organ transplant patients to prevent their bodies from rejecting the new organ, mimics the beneficial effects of fasting and has been shown in studies to significantly extend the lifespan of mice.

However, in high doses, rapamycin suppresses the immune system and can cause side effects such as headache, dizziness, chest pain, muscle pain, diarrhea, fever, and mouth sores. It is not approved for human use as a longevity medication.

Spermidine, meanwhile, is “generally recognized as safe” for human consumption by the U.S. Food and Drink Administration. Oxford Healthspan (which makes the spermidine supplement Primeadine) says the European Food Safety Agency has stated that doses of up to 6 mg per day are safe for humans.

“Spermidine may be an alternative to rapamycin,” said Professor David Weinkove, President of the British Society for Research on Ageing.

A study published in Cells (2021) found that both rapamycin and spermidine affect autophagy in similar ways.

However, Professor Weinkove points out that most of the clinical research supporting spermidine has not yet been conducted in humans.

‘Research shows that spermidine can slow aging, but not reverse it. It is not known whether it also works in humans.’

He cites a 2022 study published in the journal Neurology by researchers in Germany and Austria. They gave 100 people daily spermidine supplements or a placebo for a year and found that there was no improvement in terms of brain performance and memory.

Dr Mohammed Enayat, a GP and founder of HUM2N, a private London clinic for longevity research, is also cautious: ‘Spermidine appears to have shown benefits in mouse studies by supporting key processes involved in ageing, including cell renewal.’

But there is little evidence that this is also the case in humans, he says.

More important, he adds, are mobility, strength and “a Mediterranean diet based on whole foods, mainly plants, plus an active, stress-free lifestyle.

Dr Clare Nieland, a GP at HOOKE, an optimal health clinic in London, agrees that it is important to get the basics of good health in order first, but adds: ‘There is no harm in taking spermidine.’

And supplements aren’t cheap: Primeadine (£75 for a month’s supply, oxfordhealthspan.com); Advanced Spermidine (£34 for a two month supply, vitality-pro.com); Liposomal Spermidine (39.99 for a month’s supply, youthearth.com).

Please note that most spermidine supplements contain wheat germ. These are not suitable for people with celiac disease or a wheat allergy.

Always consult your doctor before making significant changes to your diet or starting a new dietary supplement, especially if you have underlying health conditions or are taking medications regularly.