THE FACTS

It sounds like a joke, or perhaps just an urban legend that grew out of Dr. Seuss’s “Green Eggs and Ham.” But food scientists say this one is no myth. The reality is that green potatoes contain high levels of a toxin, solanine, which can cause nausea, headaches and neurological problems.

Potatoes naturally produce small amounts of solanine as a defense against insects, but the levels increase with prolonged exposure to light and warm temperatures.

The green color is actually caused by high levels of chlorophyll, which by itself is harmless. But it is also a sign that levels of solanine, which is produced at the same time as chlorophyll, have increased as well.

Image Credit... Leif Parsons

According to a recent report by Alexander Pavlista, a professor of agronomy and horticulture at the University of Nebraska, Lincoln, a 100-pound person would have to eat about 16 ounces of a fully green potato to get sick. That is the weight of a large baked potato.