Since 1990, the number of overweight and obese children has risen sharply on all continents, almost doubling. Although the USA has the highest prevalence, other countries are not far behind. In Southern Europe, including Greece, Italy and Spain, 10 to 15% of children are obese, while rates in Eastern European countries are slightly lower but rising rapidly. The harmful consequences of this epidemic are already evident: high blood pressure in children, type 2 diabetes and other problems. In adults, these problems significantly increase the risk of heart attacks, strokes, liver disease, obstructive sleep apnea, arthritis and certain cancers – many of which now occur at a younger age. However, children with obesity can also develop other health problems that severely affect their quality of life.
Overweight Children are More Likely to Develop Skin Diseases Related to the Immune System
Childhood obesity can contribute to the development of common immune-mediated skin diseases (IMSDs) such as alopecia areata, atopic dermatitis and psoriasis, according to research. A healthy weight could potentially help reduce the risk of developing these skin conditions. A recent study in the Journal of Investigative Dermatology, describes the results of an analysis of 2,161,900 Korean children from 2009 to 2020 to investigate the association between obesity or dynamic changes in body weight and the development of IMSDs. These skin diseases have detrimental effects on the quality of life, including emotional, physical, social and functional well-being, of children and their families. Although several biologics have been shown to be effective in treating children with atopic dermatitis or psoriasis, limited treatment options and a lack of clinical trials for systemic therapies remain a significant treatment challenge. The exact mechanisms responsible for the involvement of obesity in the development of chronic inflammatory skin diseases, including psoriasis, atopic dermatitis and malignant skin diseases, remain unclear.
The study found that obese children are more likely to develop common IMSDs than normal-weight children. Among the three most common IMSDs, atopic dermatitis showed the clearest trend: children who gained weight (normal weight to overweight) had a higher risk of developing atopic dermatitis than children who maintained their normal weight, and children who lost weight (overweight to normal weight) had a lower risk of developing atopic dermatitis than children who maintained their overweight.These results underline the importance of paying attention to weight maintenance in children who are already in the normal weight range, as this can help to reduce the risk of developing atopic dermatitis. In addition, the prevention of excessive weight gain and targeted weight loss, including the introduction of healthy eating strategies in children with obesity to prevent atopic dermatitis, especially before school age, should be encouraged.
Increased Risk of Iron Deficiency
Other studies show that children and adolescents who are overweight or obese have a significantly higher risk of iron deficiency. Researchers from the School of Food Science and Nutrition examined thousands of medical studies from 44 countries involving people under the age of 25, in which iron levels and levels of other vitamins and minerals were recorded alongside weight. They found that iron deficiency occurred in both underweight and overweight children and adolescents. In contrast, zinc and vitamin A deficiencies were only observed in malnourished children, leading the researchers to conclude that iron deficiency in overweight children is likely due to inflammation that disrupts the mechanisms regulating iron absorption.
Iron deficiency in children negatively affects brain function, including attention, concentration and memory, and may increase the risk of conditions such as autism and ADHD. This research is hugely important given the high prevalence of obesity in children. The scientists hope it will lead to greater awareness of the problem by doctors and improve clinical practice and care. However, it is increasingly recognized that vitamin and mineral deficiencies can also occur in overweight and obese people who eat a nutrient-poor but energy-rich diet, known as “hidden hunger”.
In high-income countries, it is associated with ultra-processed foods that are high in fat, sugar, salt and energy. However, in low- and middle-income countries, obesity is often associated with poverty and monotonous diets with limited choices of staple foods such as maize, wheat, rice and potatoes. Many developing countries now face a double burden of malnutrition and overnutrition due to the rapid increase in the global prevalence of obesity in recent decades, particularly among children aged five to 19. These alarming figures emphasize that screening for micronutrient deficiencies in the context of the dual burden of malnutrition remains critical to children’s health. Iron status can be an early warning sign, but the real issue is that persistent inflammation leads to heart disease, diabetes and fatty liver. Increased physical activity and better nutrition have been shown to reduce inflammation and improve iron status in children.
How a Child’s BMI Affects their Lung Lunction
An abnormal BMI in children – be it high or low – can also be associated with impaired lung function. However, if the BMI is normalized before the children reach adulthood, the impairment can be compensated for, report researchers from the Karolinska Institute.
In one in ten people, the development of lung function is impaired in childhood, so that they cannot reach maximum lung capacity in adulthood. This increases the risk of serious health problems such as cardiovascular disease, lung disease and diabetes. One risk factor associated with impaired lung function development is abnormal weight and height. The most commonly used body mass index (BMI) takes weight into account, but not muscle and fat composition. Previous studies have looked at the correlation between BMI and lung function, with varying results. Swedish researchers now show that there is indeed a correlation when BMI deviates from normal – in both directions.
Early Intervention is Important
The participants could be divided into different BMI groups, which began to differ at the age of two. In contrast to children with a normal BMI, those with a persistently high BMI or an accelerating increase in BMI as adults had impaired lung function, primarily due to restricted airflow in the lungs, a condition known as obstruction. Interestingly, the researchers found that in the group with an initially high BMI but a normalized BMI before puberty, lung function was not impaired in adulthood. This shows the importance of optimizing children’s growth in early childhood as well as in early schooling and adolescence. A stable low BMI could also be associated with reduced lung function caused by insufficient lung growth. In these cases, BMI was not normalized during the course of the study.
The current study was based on the BAMSE project, in which over 4,000 children were followed from birth to 24 years of age. BMI was measured repeatedly over this period, a maximum of 14 times. The present study includes 3,200 participants with at least four BMI measurements, and lung function was measured by spirometry at the ages of 8, 16 and finally 24 years. At this time, the function of the smaller airways was also measured via the volume of exhaled nitrogen. Urine samples were also taken so that the metabolized substances could be analyzed. The urine samples from the high BMI group showed increased levels of metabolites of the amino acid histidine, confirming the observations of other researchers who have found a similar increase in patients with asthma and chronic obstructive pulmonary disease.
How can BMI be reduced in children? Increasing daily physical activity is important, but is often not enough to significantly impact the rate of overweight and obesity in children. The increase in high-sugar products and the consumption of ultra-processed foods also contribute significantly. A diet consisting of balanced and varied foods, preferably fresh and unprocessed, as well as healthy snacks (e.g. vegetables and fruit) as an alternative to sweets, could be helpful measures to get the problem under control in the long term.