Well-treated lettuce can be eaten raw, moderate consumption is not harmful to the human body; not well-treated lettuce eaten raw to the body of the hazards mainly include bacterial infection or parasitic infection. Lettuce grows on the ground, and the distance from the soil is close, parasites or bacteria may be attached to the leaves, and ordinary washing is difficult to wash the parasites or bacteria, directly eating raw lettuce is prone to bacterial infection caused by acute gastroenteritis, which may also lead to intestinal parasitosis, the patient may appear nausea, vomiting and abdominal pain and other symptoms, but also cause increased diet and body wasting, and so on. Sufficient soaking and rinsing before washing is conducive to food safety and reduces the likelihood of bacterial infection or parasitic infection. Lettuce is a common vegetable in life, every 100g of lettuce contains 13mg of vitamin C, selenium 1.2μg, but also contains a certain amount of calcium, phosphorus, potassium and other nutrients, which can replenish the body with nutrients to maintain the normal physiological function of the body. In order to avoid the hazards of eating raw lettuce to the body, it is recommended that lettuce be cooked completely before consumption, or carefully cleaned.