Most of us have found them at the back of the kitchen cabinet. Potatoes that look fine at first glance, but with pale sprouts curling out of the skin. Many people simply cut the sprouts off and cook them anyway, assuming it’s harmless. What few realize is that sprouting is not just a cosmetic change. It’s a warning sign that the potato has started producing substances that can be dangerous to your health.

When potatoes begin to sprout, they increase levels of natural toxins called glycoalkaloids, mainly solanine and chaconine. These compounds are part of the plant’s defense system, but they are toxic to humans when consumed in higher amounts. The toxins concentrate around the sprouts, the skin, and any green areas of the potato. Cooking does not reliably destroy them, which is why heat alone does not make sprouted potatoes safe.

Eating potatoes with elevated glycoalkaloids can lead to symptoms that are often mistaken for food poisoning. Nausea, vomiting, stomach cramps, diarrhea, headaches, and dizziness are among the most common reactions. In more serious cases, people may experience confusion, low blood pressure, or neurological symptoms. Children, elderly individuals, and those with weaker immune systems are especially vulnerable.

The risk increases if the potato tastes bitter. That bitterness is a clear signal of toxin buildup and should never be ignored. Even small amounts consumed repeatedly can irritate the digestive system over time. While severe poisoning is rare, it does happen, and most cases are linked to improperly stored or sprouted potatoes that were still eaten.

Storage plays a major role in prevention. Potatoes should be kept in a cool, dark, well-ventilated place. Exposure to light and warmth accelerates sprouting and toxin production. Refrigeration is not ideal either, as it changes starch composition, but darkness and moderate cool temperatures slow the process significantly.

Sprouted potatoes are not always safe to salvage. If sprouts are small and the potato is firm with no green color, some people choose to discard the sprouts and peel deeply. However, when sprouts are long, the skin is green, or the potato feels soft or wrinkled, it’s best to throw it away. The small cost of replacing a potato is nothing compared to the risk to your health.