Under normal circumstances, vegetables like amaranth, purslane, and even common ones like rapeseed and celery, can break down in the human body to produce a photosensitive substance. Some people are very sensitive to this photosensitive substance. If they consume too much, these substances can accumulate in the body. When a certain concentration is reached, the skin of exposed areas of the body, such as the face and hands, after being directly exposed to sunlight, can lead to metabolic disorders and induce dermatitis. This is medically known as "vegetable-induced solar dermatitis."
"Vegetable-induced solar dermatitis" most commonly affects women between the ages of 20 and 40. The onset is relatively acute, usually 5 to 20 hours after consuming the vegetables. The face and the back of the hands begin to show diffuse, symmetrical edema. The texture is firm, non-shiny, and non-red. In severe cases, it can extend to the neck or forearms. After 1 to 5 days, ecchymosis or petechiae appear on the edematous areas, the color gradually deepening from light to dark. This is followed by a burning sensation, numbness, itching, and blisters, accompanied by symptoms such as headache, drowsiness, nausea, and abdominal pain.
In addition, there are also "photosensitive seafood," including shellfish, shrimp, crabs, and clams. These also contain photosensitive substances. Furthermore, some drugs and cosmetics contain photosensitive ingredients that can also trigger solar dermatitis.
Now is when wild vegetables are growing vigorously, and "vegetable-induced solar dermatitis" is most prevalent during this season or in the summer. Once "vegetable-induced solar dermatitis" occurs, it is first necessary to stop eating the vegetables related to the onset and to avoid sun exposure. For those with more severe allergic symptoms, antihistamine drugs can be used under a doctor's guidance.
Vegetables that can easily cause "vegetable-induced solar dermatitis" include: lamb's quarters, Kalimeris indica, purslane, spinach, amaranth, shepherd's purse, radish leaves, rapeseed, mustard, beet, lettuce, and buckwheat.