Recently, experts in Taiwan have pointed out that one should not eat more than 3 tangerines or oranges in a single day. This is because the daily required amount of Vitamin C can be met by consuming 3 tangerines, and eating more can be harmful to the oral cavity and teeth.
Tangerines contain carotene. If consumed in excess, the content in the blood increases sharply and accumulates in large amounts in the skin. This causes the skin in areas rich in subcutaneous fat, such as the palms of the hands, fingers, soles of the feet, nasolabial folds, and the edges of the nostrils, to turn yellow, resembling "jaundice hepatitis." The only difference is that the whites of the eyes do not turn yellow, and the color of urine and stool remains normal. This specific condition is medically known as "carotenemia" or "carotenodermia," and is also sometimes called "orange skin disease." The cause is that after a large consumption of tangerines, the carotene in the blood significantly increases. The liver cannot convert the excess carotene into Vitamin A in time, leading to a significant increase in the carotene content in the skin.
If tangerines are eaten with radishes, it can easily induce goiter. According to clinical findings by foreign experts, after cruciferous vegetables like radishes are consumed, a substance called thiocyanate is rapidly produced, which is quickly metabolized into an anti-thyroid substance called thiocyanic acid. At this time, if the human body also consumes a fruit rich in plant pigments like tangerines, the flavonoids they contain, after being decomposed by bacteria in the intestines, can enhance the effect of thiocyanic acid in suppressing the thyroid, thus inducing or causing goiter.
In addition, do not drink milk within 1 hour before or after eating tangerines, because the protein in milk will curdle and precipitate upon contact with the fruit acid of tangerines, affecting digestion and absorption. Also, do not eat tangerines before meals or on an empty stomach, as the organic acids in tangerine juice will irritate the gastric mucosa, which is detrimental to stomach health.