No, There Aren’t Parasites In Your Onions! Here’s What They Actually Are (And When You Shouldn’t Eat Them)

Have you ever cut open an onion and found one or more green sprouts nestled between the layers? It's not the most inviting effect, and your first thought is often that it's gone bad. Don't panic: it's not mold, insects, or even parasites. What you're seeing is simply an onion that's started to sprout.

The onion, unlike many other vegetables, is a bulb. This means its natural function is to store nutrients to allow the plant to regrow. When conditions permit, even far from the ground, the bulb "awakens" and gives rise to new shoots directly from the center.

Why Do Sprouts Grow Inside of Onions?

Germination can be triggered by several factors: inadequate temperatures, high humidity, exposure to light, or prolonged storage. In some cases, imbalances in the phytohormones that regulate bulb dormancy also come into play. The result is that the onion, instead of remaining "still," decides to start growing again.

This phenomenon is quite common in onions purchased in large retailers, selected for a long shelf life. However, prolonged storage also increases the likelihood that the bulb will begin its life cycle earlier than expected.

Can You Eat a Sprouted Onion?

From a food safety standpoint, it's not toxic: if the onion is still firm, free of mold and unpleasant odors, it can theoretically be eaten by removing the central shoot. However, the flavor tends to become more bitter and the texture softer: signs that the product is losing quality. The presence of shoots is therefore more of a warning sign than a real danger. It indicates that the onion is no longer fresh and that its organoleptic profile has been compromised.

We can interpret this phenomenon as an invitation to reflect on how we buy and store food: onions that are perfect on the outside, shiny and long-lasting, are not always synonymous with quality. Varietal selections geared towards yield and long shelf life often sacrifice freshness and flavor, increasing the likelihood of unwanted sprouting. If an onion has already started to sprout, it may not necessarily be worth throwing away, but it's definitely time to ask yourself how long it's been there and where it came from. Making a more informed purchase remains the best choice.