Nutrition is the key to maintaining basic metabolism and ensuring normal growth and development in children. Excessive or insufficient intake of nutrients can lead to nutritional imbalances and deficiencies, which are still one of the most important risk factors for child morbidity and mortality in developing countries. Malnutrition includes energy-protein deficient malnutrition (e.g., wasting and malnutrition) and micronutrient deficiencies (e.g., mineral and vitamin deficiencies), with some overlap between the two, and a micronutrient deficiency can be accompanied by several other micronutrient deficiencies.
Etiology of nutritional deficiencies in children
Long-term nutrient intake deficiency: e.g. feeding with porridge, rice paste, milk cake, etc., neglecting protein and fat supplementation, resulting in insufficient protein and calories in food.
Influence of diseases: such as pediatric diarrhea, recurrent respiratory infections, pneumonia, measles, gastrointestinal malformations, parasites, long-term fever, etc. Nutrient deficiency can occur due to diseases that cause chronic underfeeding or digestive and absorption disorders, as well as excessive metabolic consumption.
Complications of nutritional deficiencies in children.
Water-electrolyte disorders.
Nutritional anemia, caused by lack of hematopoietic raw materials, such as protein, iron, vitamin B12, etc.
Vitamin deficiencies, commonly deficient in vitamins A, D, B, C, etc.
Infections, due to low immune function, easily secondary to upper respiratory tract infections, thrush, pneumonia, tuberculosis, otitis media, urinary tract infections, sepsis, infantile diarrhea, etc.
Hypoglycemia, white hair hypoglycemia can occur.
1. Epidemiology of vitamins and minerals related to child nutrition
1.1 Nutritional status of vitamins and minerals in children
According to the Global Survey of Developing Countries 2000-2002, the prevalence of low weight in children under 5 years of age was about 31% and the prevalence of growth retardation was about 38%. In China, the prevalence of malnutrition caused by energy-protein deficiency in children has decreased significantly due to the abundance of food and improvement of dietary quality.
According to the 2002 China Population Nutrition and Health Survey Report, the prevalence of low weight and growth retardation among Chinese children under 5 years old was 7.8% and 14.3%, a decrease of 56.7% and 55.2%, respectively, compared with those in 1992. Compared with the findings of the 2002 China Population Nutrition and Health Survey Report, the rates of severe low weight and growth retardation among children under 5 years of age decreased by 24% and 31%, respectively.
However, the 2002 China Population Nutrition and Health Survey Report pointed out that children in China still have vitamin deficiency and calcium deficiency problems that need to be addressed.
The survey results of Guo Junsheng et al. in 2000 showed that 56%-63% of children aged 6-8 years in China had insufficient serum vitamin A; 26% had insufficient vitamin B1; 45% had insufficient vitamin B2; 18% and 15%-17% had below normal values of hemoglobin and vitamin C, respectively.
In 2006, Zhu Haiyan et al. showed that the protein and energy intakes of 561 preschool children in five nurseries in Shanghai met the recommended nutrient intake (RNI) standards (93.1% and 108.8%, respectively), but the intakes of calcium and vitamins A and C were significantly insufficient.
The results of a survey conducted by Zhao Liyun et al. in 2008 showed that the vitamin A deficiency rate of children under 5 years old in China was 9.1% and the marginal deficiency rate was 41.8%. This is basically consistent with the results of the 2002 Survey Report on the Nutrition and Health Status of the Chinese Population, which indicated that the vitamin A deficiency rate among children aged 3-12 years was 9.3% and the marginal deficiency rate was 45.1%.
1.2 Mechanism of the role of vitamins and minerals in the healthy growth of children
Vitamins and minerals are indispensable nutrients for human growth and development. Malnutrition in children is often accompanied by multiple vitamin and mineral deficiencies and insufficiencies, among which vitamin A, B1, B2, B6, B12, C, D, folic acid deficiency and calcium insufficiency are more common. Vitamin and mineral deficiencies and insufficiencies can adversely affect the growth and development of children, especially their intelligence, physical fitness, immune levels and attention span. The mechanisms of action of these vitamins and minerals on children’s growth and development are described below.
1.2.1 Vitamin A
Promotes growth, maintains the integrity of mucosal epithelial cells, promotes bone and dental development and immunity, as well as the formation of retinal intraretinal optic violet and retinal blue matter and adaptation to dark vision.
1.2.2 Vitamin B1
Coenzyme of various oxidative decarboxylase systems, plays an important role in glucose metabolism, and has a large impact on cardiac and neurological functions in particular.
1.2.3 Vitamin B2
A component of flavoprotein-like coenzymes, involved in hydrogen ion conversion and cellular respiration in the metabolism of sugars, lipids and amino acids in the body.
1.2.4 Vitamin B6
There are three active forms of pyridoxal, pyridoxal and pyridoxamine, which are transformed into coenzymes after phosphorylation, acting on decarboxylase, transaminase and desulfurase, etc., playing an important role in protein-fat metabolism.
1.2.5 Vitamin B12
It is absorbed by binding with internal factors in the stomach, promotes the utilization of folic acid, participates in the synthesis of nucleic acid, porphyrins and purines, promotes the development and maturation of red blood cells, and plays an important role in the metabolism of hematopoietic and neural tissues.
1.2.6 Vitamin C
Participates in tissue redox reactions, promotes connective tissue maturation and collagen formation, maintains its integrity, promotes iron absorption and folate metabolism, and participates in the synthesis of adrenocortical hormones, immunoglobulins and neurotransmitters.
1.2.7 Niacin
An important component of coenzyme I and II of dehydrogenase in the body, involved in the metabolic process of sugar, fat and protein, maintaining the soundness of skin, mucous membrane and nerve tissue.
1.2.8 Pantothenic acid
Plays an important role in the synthesis and degradation of fatty acids, the metabolic processes of steroid hormones, vitamin A, D and heme A synthesis, and in the metabolic processes of tricarboxylic acid cycle and oxidative energy supply, membrane phospholipid synthesis, oxidative degradation of amino acids and vitamin B12 synthesis.
1.2.9 Folic acid
Its active form, tetrahydrofolate, is a coenzyme of the one-carbon group and is involved in the metabolism of porphyrins, nucleoproteins and methyl groups, as a raw material for the synthesis of nucleic acids, and has a role in promoting bone hematopoiesis.
1.2.10 Vitamin D
It promotes the absorption of calcium and phosphorus in the intestinal wall and its precipitation in bones, regulates the concentration of serum alkaline phosphatase, maintains the concentration of calcium and phosphorus in blood, and facilitates the growth and development of bones and teeth. In addition, vitamin D can participate in the regulation and differentiation of immune cells through a variety of mechanisms, in a direct or indirect manner, and is involved in the regulation of the body’s immune system at several levels; overall, vitamin D plays an immunosuppressive role. Animal studies have shown that vitamin D supplementation has a preventive effect on certain autoimmune diseases, such as multiple sclerosis and type 1 diabetes.
1.2.11 Calcium
The main component of human bones and teeth, ionized calcium is involved in regulating neuromuscular excitability, promoting blood clotting, glandular secretion and cardiac activity, as well as activating various enzymes in the body such as ATPase, lipase, succinate dehydrogenase, etc.
1.2.12 Phosphorus
It is a major component of bones and teeth, a constituent of all cell nuclei and cytoplasm, participates in acid-base balance, and forms many enzymes that play a key role in energy conversion, nerve impulse transmission and the metabolism of sugar, protein and fat.
2. The role of vitamin and mineral deficiencies in the healthy growth of children
2.1 Clinical studies of multivitamin and mineral deficiencies limiting healthy growth in children
2.1.1 Skeletal development
Calcium, phosphorus, vitamin D and vitamin A play an important role in children’s growth and skeletal development.
Calcium is a major component of bones and teeth and plays an important role in maintaining muscle excitation and enzyme activation. Calcium deficiency in children can lead to childhood rickets, growth arrest, osteochondrosis, and fractures.
There is also a relationship between bone development and blood phosphorus concentration, with a calcium-phosphorus product of 35-40
mg/dl in order to most effectively play the role of bone mineralization. In addition, phosphorus can increase collagen synthesis, and severe phosphorus deficiency can significantly disrupt bone matrix synthesis and mineralization.
Vitamin D deficiency reduces intestinal absorption of calcium and phosphorus, which ultimately interferes with the ossification process and is the underlying cause of nutritional deficiency rickets.
Vitamin A is also necessary for normal bone growth and development, and vitamin A deficiency can lead to low bone calcium levels.
2.1.2 Immune function
Vitamin A and D deficiency and imbalance in calcium and phosphorus metabolism will decrease immune function in children and increase their morbidity and mortality.
In a state of subclinical vitamin A deficiency, a reduction in the body’s barrier resistance to pathogenic microorganisms can occur, causing acute infections, while infectious diseases also increase the consumption of vitamin A stored in the liver.
Vitamin D deficiency is positively correlated with the incidence of infections. The cellular immunity of children with vitamin D deficiency rickets combined with respiratory tract infections is low.
Studies have confirmed that imbalance of calcium and phosphorus metabolism in the body and immune function interact with each other, and there is a very obvious constraint between the two.
2.1.3 Intellectual development
Calcium, niacin, vitamins B1, B6, B12, A, C, D and folic acid are closely related to the intellectual development of children.
Inadequate calcium often results in abnormal sexual arousal, and even small stimuli can cause mental agitation; when calcium is sufficient, even stronger mental stimuli can be coped with well, indicating that inattention in children is related to calcium deficiency.
Pellagra caused by niacin deficiency can cause cognitive impairment and even dementia.
Various other B vitamins, especially B1, B6, B12 and folic acid, are necessary for the synthesis of neurotransmitters, and deficiencies can affect children’s intellectual development and cause a variety of neurological symptoms.
Vitamin C can affect the activity of several hydroxylases related to neurotransmitter metabolism, and can also play a neuromodulatory role by changing the transport and localization of carriers in the cell membrane, which is an extremely important nutrient for improving brain function.
Vitamin A can promote brain development, children’s long-term vitamin A intake is insufficient can lead to mental retardation.
Vitamin D. Studies have confirmed that 1,25(OH)2D3 promotes the expression of nerve growth factor and activates the growth of neurosynapses in hippocampal bodies transplanted into in vitro cultures. Low levels of vitamin D before birth can lead to brain enlargement, deformation, follicular enlargement, and inhibition of nerve growth factor expression in newborn rats.
2.1.4 Synergistic effects exist between vitamins and minerals
Vitamin A is an important cofactor in the synthesis of glycoproteins, and chondroitin sulfate in the skeletal matrix is an important glycoprotein. Lack of vitamin A affects bone growth in children; vitamin D is closely related to calcium absorption and osteogenesis; vitamin C helps hydroxylate lysine and proline in the synthesis of collagen, thus promoting the synthesis of collagen tissue; B vitamins improve children’s appetite and promote other B vitamins can improve children’s appetite and promote the absorption of other nutrients. Therefore, multivitamin and mineral supplementation has a synergistic effect on promoting children’s growth and development and improving immune function.
2.2 Clinical evidence that multivitamin and mineral supplementation improves healthy growth in children
Malnutrition has been a major problem limiting healthy child growth, especially in developing countries, and the risk of child mortality is directly related to the degree of malnutrition. Multiple or single nutrient deficiencies in dietary nutrition, such as vitamin-mineral deficiencies and insufficiencies, are an important cause of growth limitation in children.
In recent years, many studies at home and abroad have confirmed that multivitamin and mineral supplementation can not only prevent and correct one or more nutrient deficiencies in the general population and special populations, but also help in the prevention and treatment of certain diseases, such as goiter, rickets, beriberi and pellagra. This is beneficial for children’s growth and development, neural coordination, intellectual level and bone health.
A study by Zhu Haiyan et al. in 2006 reported that a daily multivitamin tablet supplement (each tablet contains 5000 IU of vitamin A, 400 IU of vitamin D, 30 IU of vitamin E, 11.5 mg of vitamin B, 1.7 mg of vitamin B2, 2 mg of vitamin B6, 6 μg of vitamin B12, 0.4 mg of folic acid, 20 mg of niacinamide, and 60 mg of vitamin C 60 mg), the results: the height and weight of children in the 6-month supplementation group increased significantly (p<0.05) compared with the unsupplemented group; after 1 year of supplementation, the weight of children in the supplementation group significantly exceeded the level of children of the same age (p<0.05).
Reading speed and working ability were significantly higher in the supplemented group compared to the control group (p<0.01);< p="">
Math scores and the sum of language and math scores were also significantly higher than in the control group (p<0.05);< p="">
Children in the supplemented group had significantly lower numbers of colds, other discomforts, and total illnesses than the control group (p<0.001). < p="">
A randomized study in India in 2007 confirmed that daily supplementation of salt fortification (containing ferrous sulfate, vitamins A, B1, B2, B6, B12, folic acid, niacin, pantothenic acid, and iodine) given to children aged 7-11 years for a total of 1 year resulted in
Hemoglobin, red blood cell count, urinary iodine level and serum vitamin A were significantly improved in the supplemented group compared to baseline (p<0.05);< p="">
There was no 1 case of stomatitis (prevalence 30.4% at baseline);
Academic performance (mean score) was significantly higher than in the control group (p<0.05). < p="">
A randomized controlled study in Turkey in 2002 confirmed that the use of vitamin D (300,000 IU), calcium (3
g/d) or a combination of vitamin D and calcium for children (aged 6-30 months) with nutritional deficiency rickets for a total of 4 weeks of treatment, with the following results.
Serum calcium ions increased significantly (p<0.05) compared to baseline levels in all groups of children;< p="">
Serum alkaline phosphatase decreased significantly in all groups (p<0.05);< p="">
The combined vitamin D and calcium treatment group was more effective than the vitamin D or calcium alone group.
In conclusion, malnutrition is considered to be an important cause of limiting healthy growth in children, and malnutrition is highly likely to cause multivitamin-mineral deficiency and insufficiency in children. Ensuring adequate intake of vitamins and minerals during childhood can help improve the nutritional status of children’s micronutrients, promote their growth and development, improve their non-verbal intelligence, as well as reduce the incidence of colds and diarrhea in children. Therefore, reasonable vitamin and mineral supplementation plays a crucial role in improving children’s nutrition.
3. Expert consensus
Malnutrition in children is often combined with vitamin deficiencies and mineral deficiencies.
Vitamins and minerals play an important role in the healthy growth of children.
Vitamin deficiency and mineral deficiency may affect growth, bone development, immune function, hematopoietic function and intellectual development of children.
Proper multivitamin and mineral supplementation can help improve the nutritional status of children’s micronutrients, which may be beneficial to ensure normal growth and development, bone development, and intellectual development, as well as improve children’s immune function.