One of the most profitable American crops is something you won’t find in the produce aisle. Though tobacco production has declined in recent years, the crop still abundant, with farmers in the U.S. growing more than 710 million pounds of the plant in 2017. Tobacco is surprisingly nutritious—but it's also toxic in its pure state, which is why throughout its history, humans have been more interested in the plant as something to smoke rather than something to eat.

Native Americans discovered the psychoactive effects of nicotine relatively early in human history. The oldest archaeological evidence of tobacco residue in a smoke pipe dates back 3000 years ago—around the same time people in modern Alabama, where the pipe was found, began cultivating foods like sunflower and squash. It's even possible that the desire to grow tobacco spurred agriculture in the area, even though it was never a food source.

We know why Native Americans cultivated the plant—smoking it played an important role in sacred rituals—but how they learned it was something that was enjoyable to smoke in the first place is less clear. It may be that South American herbalists stumbled upon its dopamine-boosting effects when studying plant life in their environment. In order to know which plants were poisonous and which had medicinal benefits, herbalists experimented with every plant they could find, and after sniffing ground-up tobacco leaves they may have realized it was something special. Another possibility is that someone came across a wild tobacco plant that had caught fire accidentally and discovered the pleasure of inhaling the smoke that way.

Tobacco gained new levels of popularity when the first European explorers arrived on American shores in the 15th and 16th centuries. Native tribes shared tobacco pipes with the visitors and gave them the dried leaves and seeds to take home with them. In 1612, John Rolfe planted the first commercial tobacco crop in Virginia, and with scientific evidence of the dire health risks still centuries away, recreational tobacco use spread across the world.

People have chewed, smoked, and snorted tobacco to reap the desired effects, but it's never been common to eat it. European colonists at Jamestown cultivated the plant before they started growing other crops, and following a winter when two-thirds of the residents starved to death, authorities mandated that farmers must grow food in addition to tobacco.

Though it isn't a produce item, tobacco does have some impressive nutritional qualities. The plant contains Fraction-1-protein (F-1-p): a type of protein that's odorless, colorless, and non-allergenic with a cholesterol-lowering amino acid composition. Tobacco F-1-p has proven more beneficial than the same protein extracted from soy, corn, and dairy, and it may be one of the healthiest proteins found in nature.

Unfortunately, tobacco also contains the toxic chemical nicotine (a natural pesticide) which negates any nutritional properties it has. Even if someone tried to eat the leaves in their raw state, they would get sick or possibly even die from nicotine poisoning. That's why when European colonists were starving to death, they didn't try turning their tobacco crops into salads.

Today the dangers of tobacco are indisputable, but the crop has the potential to save lives as a food source. When extracted from the plant, tobacco F-1-p is completely safe to consume, and it can be cheaply sourced from the many farms already growing tobacco around the world. Though the nutritional benefits of tobacco have been known for years, it's still an untapped resource—largely thanks to the stigma attached to the crop.