By Climate Central
Plants need carbon dioxide for nourishment and a certain amount of it in the atmosphere helps trap enough heat to keep the planet from freezing. So how can something be so important but also potentially dangerous?
Easy. Just like our bodies, the climate system can become unbalanced if it gets too much of a good thing. There are all sorts of substances that are important — or even crucial up to a point — but bad for us when we get too much.
Among them:
- Medications like aspirin which can cause gastrointestinal bleeding, or acetaminophen (the generic version of Tylenol), which can be toxic to the liver.
- Vitamins A, D, E and K which are toxic in high doses.
- Sunlight, which can cause sunburn or even lethal skin cancer.
- Salt keeps your fluids in balance but too much can cause or worsen high blood pressure.
- Insulin helps regulate body sugar but get too much and it can lead to coma and even death.
This originally appeared on Climate Central.
