Severe obesity in early childhood could halve life expectancy, study shows
A groundbreaking study revealed at the European Congress on Obesity in Venice, Italy, on 12-15 May, 2024, has provided a quantitative analysis on how childhood obesity affects life expectancy and long-term health. This research, conducted by stradoo GmbH, a life sciences consultancy based in Munich, Germany, involved collaboration with experts from universities and hospitals across the UK, Netherlands, France, Sweden, Spain, the U.S., and Germany. Dr. Urs Wiedemann of stradoo presented these findings, highlighting the critical influence of obesity’s onset age, its severity, and its duration on lifespan.
The study shows that early-onset obesity has particularly severe consequences. For instance, a four-year-old with severe obesity (BMI Z-score of 3.5), who does not manage to reduce their weight, is projected to have a life expectancy of just 39 years, nearly half the average lifespan.
Dr. Wiedemann noted the sporadic nature of existing data on the significant lifespan reduction associated with childhood obesity and its potential health complications, such as cardiovascular diseases and type 2 diabetes. The study aimed to refine our understanding of these impacts to better shape preventative strategies and treatment approaches, ultimately extending lifespan and enhancing quality of life.
To achieve this, the research team developed a model focused on early-onset obesity. This model considered several critical variables, including the age when obesity begins, the duration of obesity, irreversible health risks that persist despite weight loss, and the severity of obesity, measured by BMI Z-scores.
BMI Z-scores, which adjust body mass index values for age and gender, were central to the analysis. For example, a 4-year-old boy with a typical height of 103 cm and a weight of 19.5 kg would have a BMI Z-score of 2, marking the onset of obesity. More severe cases, like a child of the same age and height weighing 22.7 kg, would have a BMI Z-score of 3.5, indicative of severe obesity.
The findings were supported by data from 50 clinical studies involving over 10 million participants, with approximately 2.7 million aged between 2 and 29. This large-scale data analysis underscored the heightened risk of developing comorbidities such as type 2 diabetes and cardiovascular diseases with higher and earlier BMI Z-scores.
For instance, a child with a BMI Z-score of 3.5 at age 4, without weight loss, faces a 27% likelihood of developing type 2 diabetes by age 25 and a 45% chance by age 35. In comparison, a child with a BMI Z-score of 2 at the same age would have significantly lower risks (6.5% by age 25 and 22% by age 35).
The research also demonstrated the life-extending potential of early weight loss. A child with severe early-onset obesity (BMI Z-score of 4 at age 4) who does not lose weight would have an expected lifespan of 37 years and a 55% risk of developing type 2 diabetes by age 35. Conversely, reducing their BMI Z-score to 2 by age 6 could increase their lifespan to 64 years and lower their diabetes risk to 29%.
The findings also highlighted the greater benefits of earlier weight loss over delaying weight reduction. However, the model did not consider certain variables such as the underlying causes of obesity, genetic factors, or the complex interplay of different comorbidities, which may affect the outcomes.
In conclusion, Dr. Wiedemann stressed the severe impact of childhood obesity on longevity and health, advocating for early intervention and consistent management to prevent the onset of severe health conditions. The study reinforces the critical nature of childhood obesity as a life-threatening condition that requires immediate and sustained medical attention.