Spermidine: which foods contain it?

What is spermidine?

Spermidine belongs to the polyamines, small nitrogen-containing molecules that carry two or more amino groups. The three main ones are spermidine, spermine and putrescine. According to Muñoz-Esparza and colleagues (Foods, 2021), they are found in all living organisms; they are stable in acid and alkaline conditions and dissolve very well in water, which matters for cooking.

Which foods contain the most?

The University of Barcelona team measured polyamines in 109 foods sold in Spain over the previous five years, a total of 1,406 samples in eight categories. Wheat germ stands out: 440.6 mg of polyamines per kg, far more than any other food in the study, and spermidine was the main polyamine in almost all cereals. The authors link this to germination, the stage at which plants build up these compounds.

The database by Atiya Ali and colleagues (2011), built from published studies, also gives values per serving. At the top it lists cooked soybeans (9.7 mg per 190 g), peas (9.1 mg per 140 g), pear (6.6 mg per 125 g), lentil soup (5.5 mg per 250 g), mushrooms (4.4 mg per 50 g) and broccoli (3.6 mg per 100 g).

Converting the units

Food tables use different units, which makes figures hard to compare at a glance. The 2021 study reports milligrams per kilogram, while the 2011 database reports milligrams per serving. Dividing by the serving size in grams puts both on the same footing. The table shows the arithmetic; the per-100-gram column was calculated by this page and is only as precise as the figures it starts from.

What about foods of animal origin?

In the 2021 study, meat, fish and dairy products had very variable polyamine levels, from 0.15 to 139 mg per kg. The highest came from a few cheeses (raw milk, hard and blue cheeses) and dry-fermented sausages, but this was mostly putrescine. In fresh meat and fish the main polyamine was spermine, and fresh milk and fresh cheese contained extremely little.

Cheese shows how much the figures vary: the 2011 database reports 199.5 mg of spermidine per kg for a cheddar matured for one year (three British samples), but from zero to 43.0 mg per kg for ripened Spanish cheeses.

Why do the figures vary so much?

According to Muñoz-Esparza and colleagues, the level in a plant food depends on the cultivar, the location, the climate and the growing and harvesting conditions. The 2011 database notes large differences between studies, and even between samples of the same food within a study. The values on this page are therefore orders of magnitude measured on specific foods, not the content of your plate.

Five questions to ask of any food composition figure

1. Which unit is it: per kilogram, per 100 grams or per serving?
2. Is the food raw, cooked or processed, and how was it cooked?
3. Is the figure one compound (here, spermidine) or a total of several (here, all polyamines)?
4. Where and when were the samples taken, and how many were there?
5. Is it an average of several samples or a single measurement?

Applying these questions to the figures above explains most of the differences. The wheat germ figure is a total of polyamines, the mushroom figure an average of spermidine, and the database values per serving depend on serving sizes. The 2011 database also notes large differences between studies, and even between samples of the same food within a study.²

Does cooking change the content?

Often, yes. The 2021 study compared thirteen foods raw and cooked in four ways. Boiling and grilling cut polyamines by up to 64%, partly because they pass into the cooking water. Microwave and sous-vide cooking left levels practically unchanged. Boiling did not change the content of some vegetables, such as peppers and peas.

Cooking and the water it leaves in

Because polyamines dissolve very well in water, the way a food is cooked changes what stays in the pan or on the plate. In the 2021 study, boiling and grilling cut polyamine content by up to 64%, partly because the compounds pass into the cooking water, whereas microwave and sous-vide cooking left the levels practically unchanged.¹ A dish that keeps its cooking liquid, such as a soup, could therefore be expected to hold on to part of what a boiled food would otherwise lose, although the sources read did not test soups specifically. The database lists lentil soup, a prepared dish, alongside raw ingredients.

None of this turns a food into something to seek out or avoid. It shows how much of a published figure depends on method. For related food composition pages, see taurine, betaine and glycine; for the rules behind what a pack may say, read how to read a food label. The group is collected in food composition guides.

What does EU regulation say?

A spermidine-rich wheat germ extract (Triticum aestivum) is on the Union list of novel foods: Commission Implementing Regulation (EU) 2020/443 amended its specifications. This page is about everyday foods, not about that extract.

What this page does not say

• It attributes no property to spermidine.
• It recommends no amount, per day or per meal.
• The levels come from foods sold in Spain and from published studies: those in your food may differ.
• It does not cover the wheat germ extract authorised as a novel food.

When to ask for advice

To adapt your diet to your situation, a doctor or dietitian can advise you. This page presents food composition data and does not replace medical advice.

Frequently asked questions