Every flu season, doctors remind us to get vaccinated — yet for many people over 65, the same shot that protects a younger person barely registers. A new study points to something surprisingly simple that might change that.

• A 2026 study in the journal Aging Cell found that spermidine, a natural compound found in foods like wheat germ and mushrooms, strengthened antibody responses to COVID-19 vaccines in adults over 65.
• Vaccine "nonresponders" who took a daily spermidine supplement for 13 weeks developed noticeably higher, more effective antibody levels than those on a placebo.
• Spermidine appears to work by easing immunosenescence, the natural decline in immune function with age, and by supporting autophagy, the body's cellular clean-up process.
• The trial involved only 40 participants, so researchers are calling this an early but promising signal rather than a firm recommendation.
• Spermidine occurs naturally in everyday foods — wheat germ, mushrooms, aged cheeses, soybeans, and whole grains — many of which are already part of traditional Indian diets.

Yes, at least according to early clinical research. A study published in Aging Cell in 2026 found that spermidine, a compound our bodies make naturally and one we also get from food, may help older adults respond better to vaccines. Researchers from the Max Delbrück Center for Molecular Medicine, Oxford University, and Cardiff University gave 40 healthy adults aged 65 and above either 6 milligrams of spermidine or a placebo, daily, for 13 weeks after their third COVID-19 vaccine dose. Among the volunteers who had responded poorly to earlier vaccinations, the spermidine group developed markedly stronger antibody activity against viral variants, with no reported side effects. It is a small study, but it adds to a growing body of evidence that what we eat can quietly shape how well our immune system does its job.

Why Vaccines Work Less Well as We Age

As we get older, our immune system undergoes changes researchers call immunosenescence — a gradual decline in the immune system's ability to recognise threats and mount a strong defence. This is exactly why flu shots and other vaccines are sometimes less protective for people in their sixties, seventies, and beyond, even though this age group faces the highest risk from infections. The study's lead researchers, Dr. Katja Simon and Dr. Ghada Alsaleh, noted that some older adults simply "do not develop strong protection, even after repeated vaccination." Their work set out to find whether a natural compound could help close that gap.

What Spermidine Actually Does Inside the Body

Spermidine is a polyamine compound that every cell in the body produces on its own, and levels tend to drop as we age. In the study, daily spermidine supplementation lowered markers of immunosenescence and increased autophagy — essentially the body's way of clearing out old, damaged cell components so healthier ones can take their place. Researchers believe this cellular "spring cleaning" may be part of why immune cells responded more effectively after vaccination.

Where to Find Spermidine on Your Plate

The good news is that spermidine does not need to come from a supplement bottle. It occurs naturally in wheat germ, mushrooms, aged cheeses like parmesan and cheddar, soybeans, green peas, and whole grains — foods that already have a place in most Indian kitchens. A daily bowl of whole grains, lentils, or a wholesome grain-and-nut mix is a simple way to build these foods into your routine without overhauling your diet.

Should You Wait for a Supplement, or Just Eat Well?

The researchers themselves are cautious. Dr. Simon pointed out that "larger studies will be needed to determine whether spermidine can consistently improve vaccine responses," and a 40-person trial is far too small to base big decisions on. But there is little downside to leaning further into whole grains, mushrooms, and legumes — these foods come with fibre, protein, and other nutrients that support healthy ageing regardless of what future vaccine research finds. Think of this less as a supplement to chase and more as one more reason to keep real, whole foods on your plate as you age.

If you're looking for an easy, everyday way to bring more whole grains into your diet, our Multi Grain Ladoo blends five wholesome grains with nuts and pure ghee — a small step in the same direction as the food-first approach this research points to.

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Frequently Asked Questions

1. What is spermidine, and where is it found naturally?

Spermidine is a natural polyamine compound produced by every cell in the body, though levels decline with age. It is also found in foods including wheat germ, mushrooms, aged cheeses like parmesan, soybeans, green peas, and whole grains — many of which are already part of everyday Indian cooking.

2. How did spermidine help vaccine responses in the 2026 study?

Researchers gave 6 milligrams of spermidine daily for 13 weeks to adults aged 65 and above who had previously responded poorly to COVID-19 vaccines. Those receiving spermidine developed notably stronger antibody activity against viral variants compared to the placebo group, with no reported side effects.

3. What is immunosenescence, and why does it affect vaccines?

Immunosenescence is the gradual decline in immune function that comes with age, making it harder for the body to mount a strong defence. This is why vaccines are often less protective for people over 65 — the immune cells that generate antibodies are less responsive than in younger adults, even after repeated vaccination.

4. Should older adults take a spermidine supplement based on this research?

Not yet. The trial involved only 40 participants, which is too small to support a firm recommendation. Researchers are calling it an early but promising signal. Eating more spermidine-rich whole foods — wheat germ, mushrooms, legumes, and whole grains — is a low-risk way to increase intake while larger studies continue.

5. What is autophagy, and how does it relate to immune health?

Autophagy is the body's cellular clean-up process, breaking down and recycling old, damaged cell components. Spermidine appears to stimulate autophagy, which may help immune cells function more effectively. Declining autophagy with age is thought to contribute to the reduced immune responsiveness seen in older adults.