Lactoferrin is a natural substance extracted from milk and is generally suitable for pregnant and lactating women and infants who are deficient in lactoferrin; it is not not recommended for everyone. Doctors may not recommend lactoferrin because it is not necessary or because of other abnormalities. Allergy to lactoferrin, abnormal liver and kidney function, and patients with parenteral nutrition may have adverse reactions to eating lactoferrin, so doctors do not recommend eating lactoferrin. 1. Allergy to lactoferrin: consumption of lactoferrin may cause diarrhea, rash, itching, swelling and other allergic symptoms, and in severe cases may also cause laryngeal edema, which may easily lead to choking. 2. Abnormal liver and kidney function: abnormal liver and kidney function will The metabolic capacity is poor, and lactoferrin often needs to be metabolized by the liver and kidneys, so eating lactoferrin may increase the burden on the liver and kidneys, so doctors do not recommend it; 3, parenteral nutrition: lactoferrin generally needs to be absorbed through the gastrointestinal tract, and some patients with parenteral nutrition are prohibited from taking lactoferrin because the gastrointestinal tract cannot eat. Human and animal milk, milk powder and other foods are richer in lactoferrin. If infants and children need to supplement lactoferrin, they can take dietary supplements first, and if there is enough supplementation through food, doctors may not recommend taking lactoferrin preparations. If you can’t get enough lactoferrin through food, you may need to take lactoferrin-based preparations again.