As humans began to populate more and more areas of the planet, they inevitably discovered more sources of food. There were new species of animals to hunt or fish and new plants to cultivate or to find in the woods. Inevitably, some of these animals proved to be inedible while some plants proved to be poisonous. In some cases, as in certain mushrooms, the poisons were deadly. Other plants were thought to be toxic but really weren't. Even today, there are harmless food products that people are still wary of. Here are some foods that most people consider or considered dangerous but aren't.
The tomato is the gold standard for a harmless food that many people thought poisonous. However, the reasoning wasn't unfounded. The tomato is a member of the nightshade family, and many of its relatives are indeed toxic. The tomato plant's leaves and stems are also a bit poisonous, and unripe green tomatoes should be consumed sparingly. For many years, the tomato plant was only grown as an ornamental in Europe.
Carrageenan is a food additive that is nothing more exotic than a type of red seaweed. It is also called Irish moss, and some kinds are used to thicken dairy products such as cream or ice cream. Other kinds of Irish moss are used as emulsifiers or to form soft or rigid gels. It is not even new. People have been adding Irish moss to food since the 15th century. It has no nutritional value and is even safe for babies.
Also called MSG, this food additive is a naturally occurring salt of glutamic acid, a type of amino acid. It's found in mushrooms, cheese and other foods and is responsible for the umami taste. Umami is what gives vegetables such as portobello mushrooms their meaty taste and mouthfeel. Though many people complain that MSG gives them a headache and upset stomach, tests can't find evidence of this. No test has been able to show that MSG leads to any sort of chronic disease.
Eggplants are in the same family as the tomato, and the fruit was once thought to be deadly poisonous. Indeed, as with the tomato, the leaves and the flowers are somewhat toxic, but a person must consume a large quantity of them to become ill. In some societies, eating an eggplant was thought to lead to violent insanity.
A cousin of the eggplant and the tomato, the potato was also thought to be poisonous at one time. Indeed, if the tubers aren't harvested, the plant produces what looks like a small green tomato that is indeed a bit toxic. But back during the Renaissance potatoes were thought to bring leprosy and a rampant libido, and they were not allowed to be grown until the latter part of the 18th century.
Of course, oysters are wonderfully edible but many people believe they must only be eaten in months with the letter "r" in their names. This warning came about because these months are the cooler months of the year, and the warm months of June, July and August were when oysters tended to spoil. However, oysters can be enjoyed throughout the year if they're cooked. It is still not a good idea to eat raw oysters though many people do.
Precautions against ingesting rice are not so much for people as they are for the birds. Many people believe that throwing rice at the bride and groom at their wedding is bad for birds. The theory is that the birds eat the rice, swell up as the rice absorbs moisture and burst. Studies have shown this to be false. There are still ordinances that prohibit rice-tossing at weddings, as the stuff is simply hard to clean up.