2. Soda
The witches’ brew is notorious for growing midsections and addictions alike. But according to a 2013 review, it can also cause heart failure—and even death. After a 31-year-old woman from Monaco went to the hospital suffering from an irregular heartbeat and fainting after drinking two liters of soda a day for 16 years straight. Researchers examined six other cases and found that all excessive soda drinkers suffered from irregular heart function, erratic heartbeats, and, in the case of one unlucky patient, death. Researchers blame soda’s diuretic effects: It can dramatically lower the body’s levels of potassium, which your heart needs to function. Even though any amount of soda is more than you need, if you absolutely must get your fix, limit your intake to 16 ounces a day.
3. Carrots
These guys owe their color to beta-carotene, an antioxidant that helps prevent everything from exercise-induced asthma to cancer. But here’s the thing: It can also make your skin orange (we’re talking Oompa-Loompa orange), says certified nutrition consultant Alejandro Chabán. While vegetarians are more likely than omnivores to develop carotenemia (thanks to orange and yellow foods, especially carrots), carotene-rich nutritional supplements can also contribute. In one case study published in The Journal of Dermatology, a woman’s skin turned yellow-orange after taking too many oral carotene supplements. However, to achieve the same levels in the blood, you’d have to eat about a half cup of carrots a day for months on end. There’s no need to push it, though. Chabán recommends capping your consumption at about two cups per week.
4. Star Fruit
There’s more than one reason it’s generally used as nothing more than a garnish: Eating too much of the five-sided fruit is toxic and causes nausea, vomiting, dizziness, diarrhea, convulsions, and even death—primarily in people with kidney problems, according to research out of Brazil. While experts have not yet pinpointed the exact cause, those with kidney problems should avoid star fruit like the plague, as even small doses can be fatal. In good health? Chabán recommends eating no more than a half cup per week. If you develop persistent hiccups within five hours of eating star fruit—the most common sign of star-fruit intoxication—call your doc. An O.D., and possibly kidney problems, may be to blame.