Anorexia nervosa is a common clinical condition in pediatrics, characterized by prolonged aversion to eating and reduced food intake, with or without clinical abnormalities of gastrointestinal function. The disease can occur in any season, but the symptoms can be aggravated in summer when heat and humidity are in season. The disease can occur in children of all ages, but it is more common in children aged 1-6 years, with a higher incidence in urban children. Long-term anorexia can cause malnutrition, growth retardation, low immune function, recurrent infections, decreased responsiveness and memory, reduced brain function, delayed intelligence, and even mental depression, so it should be taken seriously.
How is appetite formed?
The mechanism by which people feel hungry and want to eat is related to the formation of appetite. When there is no food in the stomach, the blood sugar level decreases, and the tissues use less sugar, it makes people feel hungry. At this time, the feeding center in the lower thalamus is excited, and feeding activity begins. When the stomach is full of food, the blood sugar level rises, and the tissues use more sugar, the satiety center in the lower thalamus is excited, and the person feels full.
Failure to add complementary foods in a timely manner
Studies have confirmed that infants have different sensitivity periods for the addition of complementary foods, with the taste sensitivity period at 4 – 6 months of age and the food texture sensitivity period at 6 – 7 months of age. If foods of various tastes and textures are not given during this period, infants tend to refuse to eat new tastes and foods of different textures after the age of 1 year, resulting in partial eating and monotonous recipes.
Some people in China analyzed the relationship between traditional feeding and pediatric anorexia and found that frequent breast-feeding day and night during infancy, excessive weaning age, late addition of complementary foods, improper food varieties and feeding methods can cause anorexia in children around 1 year old.
Principles of adding complementary foods.
For small infants, complementary foods and weaning should be added at the right time. The principles of adding complementary foods.
① from little to much, so that infants have a process of adaptation, such as adding egg yolk from 1/4, if there is no adverse reaction, 5 – 7 days later increased to 1/3 – 1/2, gradually increased to 1.
②From thin to thick, such as starting from rice soup to thin porridge, and then gradually increase to soft rice.
③From fine to coarse, such as adding green leafy vegetables, from vegetable water to vegetable puree, and try crushed vegetables after the milk teeth erupt.
④After getting used to one kind of food, then add another kind of food, not several at the same time.
⑤ Supplementary foods should be added when the infant is healthy and has normal digestive function.
The etiology of pediatric anorexia is not only related to acute and chronic infectious diseases and the influence of drugs, but also related to feeding methods, eating habits, mental psychology, social environment, natural environment and other factors
Poor dietary habits and/or unreasonable dietary structure
High-sugar diet
Some children like to eat candy, snacks, sweet drinks, ice cream, chocolate, etc. and snack on sweet foods anytime and anywhere. Sweet food increases blood sugar concentration and stimulates the satiety center to produce a feeling of fullness, so that children do not feel hungry.
According to the survey, among children with loss of appetite, most of them never drink plain water and only drink sweet drinks, such as orange juice, fruit juice, honey water, soft drinks, etc. Many children do not drink beverages because they are thirsty, but because they like the sweet taste. These sugary drinks will naturally raise blood sugar and excite the satiety center thus producing anorexia. In addition, large amounts of sweet drinks can dilute stomach acid and other digestive juices, weakening digestive function and leading to loss of appetite.
High-fat meals
Food with high fat content stays in the stomach for a long time, stomach emptying is significantly delayed, and digestion and absorption into the intestine is slower, so hunger is not easily felt. And because of the poor function of the spleen and stomach of children, often eat fatty foods, can increase the digestive burden of the gastrointestinal tract, the spleen and stomach can not transport these foods, there will be symptoms of injury to food, can appear loss of appetite, gastric and epigastric discomfort, stomach pain, abdominal distension or dry stools.
Excessive cold drinks
Children’s gastrointestinal tract mucosa is tender and sensitive to the temperature of the ingested food. 0 ℃ ice cream into the 37 ℃ digestive tract, can stimulate the delicate gastrointestinal tract, so that the mucosal vasoconstriction and affect the secretion of digestive juices and gastrointestinal digestive function, resulting in a lack of appetite for children. Also, the high sugar content in cold drinks can cause lack of hunger in children and cause anorexia in children.
Other
Parents over-indulge their children, in the structure of the diet, protein (eggs, meat, dairy) or sugar (sweets, chocolate, etc.) accounted for too large a proportion, which in turn makes appetite decline. Normal children’s appetite will arise every 3 – 4 hours when the stomach contents are emptied and blood sugar is lowered. If the meal is not regular, snacks or candy before meals, there is always something in the stomach, blood sugar does not drop, there will be no appetite. In the long run, this will not only cause bad habits of partiality and picky eating in children, but also cause dysfunction in gastrointestinal digestion and absorption.
The specific content of balanced diet
There are many reasons for children’s lack of appetite, and prevention should be based on comprehensive intervention measures, including establishing scientific feeding methods, cultivating good eating habits and correcting the current nutritional imbalance, so as to make children’s nutritional absorption reasonable and balanced.
Family arrangement of balanced diet should mainly do the following.
①Diversification of food: Only the intake of rich variety of food can meet the demand of comprehensive nutrition, which means that the food types constituting the diet should be diversified, such as grains, vegetables, fruits, animals, milk and soy products, fats, oils and sugars, etc., should all be consumed in appropriate amounts.
②Balanced food: A balanced diet should be based on the daily supply of nutrients according to different ages, avoiding too much and not enough of certain nutrients, for example, the ratio of protein, fat and carbohydrates should be roughly 15%, 35% and 50% according to the calorie supply; the calorie distribution of three meals should be balanced, with 35% for breakfast, 35% for lunch and 30% for dinner.
③The principle of individualization: emphasize the dynamic deployment of foods with different attributes according to the individual and choose reasonable cooking methods.
Psycho-psychological factors
Forced eating
Some parents do not understand the laws and idiosyncrasies of children’s body growth, and cannot grasp how much food their children eat to meet their physiological needs, mistakenly believing that “more is better” and the more they eat, the happier the parents are. When the child does not eat much, always order and force the child to eat with parental dignity, in these cases, will make the child aversion, in the long run, easy to produce a rebellious mentality, will be more anorexic.
Attention distraction
When children eat, such as attention, through the sense of sight, smell, taste to the food color, smell, taste “taste”, so as to establish a food reflex, promote gastric secretion and improve appetite. Therefore, the entire meal process to let the child’s mind focus on eating this one thing, not to let the child eat while watching TV, not to play with toys while eating. Some parents chase their children around and feed them, or try to lure them to eat, so that the children eat passively and are not interested in eating. In the long run, all will make the appetite low. In addition, environmental changes, academic overload, parental “must-have”, and children eat a little less on the unscientific parenting mentality, the child’s mental mood will have an impact, can cause anorexia.
How does emotion affect appetite?
The activity of the higher nerve centers has an impact on the digestive, feeding and satiety centers of the stomach and intestines. When emotions are bad, the cortical response to the external environment decreases, resulting in reduced gastrointestinal secretion and peristalsis, which in turn reduces the digestion and absorption of food. As a result, food stays in the stomach for a longer period of time, people do not feel hungry and do not want to eat.
Micronutrient zinc deficiency
Zinc deficiency affects the cell renewal of tongue taste buds and the activity of salivary phosphatase, causing a decrease in taste sensitivity, resulting in loss of appetite, anorexia, xerophagia, etc., and possibly oral ulcers, map tongue, etc. Severe zinc deficiency may impair the immune function of the body and make it susceptible to infections. Zinc deficiency can impair DNA and protein synthesis in the brain, causing delayed intellectual development.
Disease factors
There are many clinical diseases that can lead to loss of appetite or even anorexia, such as acute and chronic hepatitis, chronic enteritis, various causes of diarrhea and chronic constipation and other gastrointestinal diseases, as well as systemic diseases such as tuberculosis or other acute and chronic infections. These diseases can involve the digestive system, so that the tension of the smooth muscle of the stomach and intestines is low, the secretion of digestive juices is reduced, and the vitality of enzymes is reduced, all of which can manifest as loss of appetite. In addition, such as intestinal parasitic infections, long-term constipation or long-term low-salt diet due to kidney disease, can also cause a decrease in appetite.
Drug effects
After taking some drugs (such as erythromycin, sulfonamides, etc.), due to their stimulating effect on the gastric mucosa, in addition to causing anorexia, children may also be accompanied by abdominal pain and nausea, vomiting and other phenomena. Almost all antibiotics can cause intestinal flora disorders and microecological imbalance with long-term application, resulting in abdominal distension, nausea and anorexia. In addition, children who are given too much calcium, vitamin A or D may also suffer from loss of appetite.