Expert tip: Celery, lettuce, rape, spinach, amaranth, and bok choy are photosensitive vegetables that can easily induce phytophotodermatitis.
Many people adopt a long-term vegetarian diet for weight loss. However, consuming an excessive amount of photosensitive vegetables under strong ultraviolet radiation can easily lead to phytophotodermatitis for those sensitive to sunlight.
According to doctors, common vegetables found in markets such as celery, lettuce, rape, spinach, amaranth, and bok choy are all photosensitive vegetables.
Experts point out that vetch, lamb's quarters, mustard, Kalimeris indica, purslane, red clover, and sheep sorrel are also vegetables containing photosensitive substances. Additionally, some Chinese herbal medicines also contain these photosensitive substances. Therefore, it is best to avoid excessive sun exposure after taking Chinese medicine to prevent skin reactions.
May to August is the peak season for this type of plant-induced phytophotodermatitis. During this time, excessive consumption of these vegetables followed by sun exposure can lead to symptoms such as erythema, papules, edema, and possibly ecchymosis, blisters, or even large bullae. Severe cases may present with skin ulcers and erosion; the blister fluid can be clear or bloody. The affected areas are mostly concentrated on the face, neck, and the outer surfaces of the limbs.
For most people with plant-induced phytophotodermatitis, the reaction is relatively mild, with only a feeling of heat, swelling, pain, stinging, itching, or tightness in a specific area. A small number of individuals may have a more severe reaction, with general discomfort, and in serious cases, a chain reaction including nausea, vomiting, diarrhea, and headache may occur. For those with mild reactions, recovery can be expected within about a week by avoiding sunlight. If the symptoms are severe, medical attention should be sought.
Depending on an individual's sensitivity to sunlight, people with strong allergic constitutions may develop symptoms of this condition within half an hour, or even just over 10 minutes, after consuming the aforementioned photosensitive vegetables and then being exposed to strong sunlight. Under the same conditions, non-allergic individuals may not experience symptoms until 2-3 hours later.
This condition is most likely to occur during outings in the countryside and beach vacations. For indoor workers, the chance of developing this condition can be considered negligible. Therefore, he reminds vegetarians that before traveling outdoors or needing to work in the sun, it is best not to consume these photosensitive vegetables.