It is common to hear parents complain that girls become dumber and do not perform as well as boys when they get to secondary school. This is actually an injustice to girls, not because they are not as good at learning as boys, but because after secondary school, girls are more likely to be anemic than boys! A survey of anemia among secondary school students showed that the prevalence of anemia among female secondary school students was close to 30%. It is not the case that good nutrition does not lead to anemia; the condition of many people is that overnutrition and anemia coexist. During this period, many girls suffer from menstrual disorders and a significant increase in menstrual flow, but they and their parents do not pay attention to it, which leads to long-term chronic blood loss, and because of the slow process, the girls’ pallor is “invisible”. Anemia not only affects their physical and mental health, but also directly affects their ability to learn. It used to be said that girls have less learning potential than boys and become dumber in middle school, but now it seems that it is not actually girls who are dumber, but many girls who are anemic. My neighbor Xiao Chen’s daughter, who was very smart in elementary school, began to gradually decline in her grades after middle school, and was only in the lower middle class. After iron supplementation, the child’s anemia problem was solved and her grades rose, returning to the top 15 in the class. Iron deficiency anemia affects all organs of the body and directly causes an overall decrease in comprehension, attention, logic and memory, and may also affect sleep. This has a serious impact on both adults and children. Girls have a monthly blood loss process, plus many children also control their diet to lose weight, or are partial eaters, which in turn causes malnutrition, so they become the largest group of patients with anemia. Although the various blood supplements currently on the market contain a certain amount of iron in various forms and are effective for iron deficiency anemia, they cannot replace regular iron supplements because of their low iron content. The most commonly used is ferrous sulfate tablets, which are “small pills” with good efficacy and economy. If the gastrointestinal symptoms are obvious, the dose can be reduced first and then gradually increased, the gastrointestinal symptoms will be significantly reduced. However, some people will have allergies to the drug, it is best to take under the guidance of a doctor. Usually, we should pay attention to eat more iron-rich food, such as animal liver, lean meat, egg yolk, spinach, celery, tomatoes, apricots, peaches, plums, red dates, etc. contain more iron, should eat more.