Did you know? Weight loss isn't just about shedding pounds. Individuals with abdominal obesity face a higher risk of hypertension, diabetes, and other conditions compared to those with generalized obesity.
Apple-shaped obesity resembles an apple
Also known as central obesity, this condition involves fat accumulation specifically in the abdominal region, manifested as increased waist circumference. Fat primarily deposits under the skin and within the abdominal cavity, often resulting in a waist circumference larger than the hip circumference, with relatively slender limbs. Visually, individuals with this type of obesity resemble an apple, hence the term "apple-shaped obesity."
In April 2005, the International Diabetes Federation established global definitions for metabolic syndrome, specifying waist circumference as a diagnostic criterion for central obesity: - USA: Men >102cm, Women >88cm - Europe: Men >94cm, Women >80cm - Japan: Men >85cm, Women >80cm - Chinese and Southeast Asian populations: Men >90cm, Women >80cmThe Chinese Obesity Working Group defined criteria tailored to the Chinese population: abdominal obesity is defined as a waist circumference ≥85 cm for men and ≥80 cm for women.
Visceral obesity poses greater risks
Both BMI (weight/height²) and waist circumference serve as simple anthropometric indicators for assessing obesity. However, people often rely solely on BMI to gauge obesity severity, overlooking the health hazard signals indicated by increased waist circumference.Recent studies reveal that systemic obesity (assessed by BMI) and abdominal obesity (assessed by waist circumference) play distinct roles in the development of various diseases. Individuals with abdominal obesity face significantly higher risks of complications compared to those with systemic obesity. This has been confirmed in our research on hypertension and diabetes.
Observational studies of a group of Caucasian women revealed that obese individuals face a 3.7 times higher risk of developing diabetes compared to the general population, while women with abdominal obesity have a 10.3 times greater likelihood of developing diabetes.A longitudinal study by Soochow University School of Medicine involving 2,778 participants also revealed that while some individuals experienced a decrease in BMI, their waist circumference might not significantly decrease or could even increase. Conversely, BMI could rise while waist circumference decreased. Therefore, relying solely on weight to determine obesity is misleading, as it may classify individuals with normal BMI but elevated waist circumference as low-risk, despite their actual high disease risk.
Abdominal obesity increases risk of visceral damage
BMI and waist circumference reflect different types of fat accumulation: BMI primarily indicates total body fat, while waist circumference mainly reflects visceral fat around abdominal organs. Elevated visceral fat levels or its proportion relative to total body fat pose significant health risks.Visceral fat primarily resides within the abdominal cavity, surrounding and infiltrating organs like the liver, pancreas, stomach, and intestines. When excessive visceral fat enters the digestive system, it damages organs such as the liver, leading to fatty liver disease. It also disrupts metabolism, triggering conditions like diabetes.Moreover, visceral fat impedes the body's ability to eliminate toxins normally, leading to the production of various chemicals that can trigger heart disease. It also increases the risk of cardiovascular diseases and causes arterial inflammation.Additionally, abdominal fat compresses the lungs, causing obese individuals to experience shortness of breath. The more difficult breathing becomes, the more likely it is that insufficient oxygen reaches the bloodstream, leading to generalized fatigue, compromised immunity, and even hypertension. Numerous studies using MRI and CT scans to precisely measure body fat content have confirmed that visceral fat levels provide a better indicator of multiple chronic diseases and even mortality than total body fat.
Body fat distribution in the Chinese population differs from Western populations, with abdominal obesity being predominant. Individuals whose weight falls within the normal range but whose waist circumference exceeds the normal threshold still face a high risk of hypertension, diabetes, and other diseases, yet this risk is often overlooked.
Sedentary Lifestyles Increase Susceptibility to Abdominal Obesity
Numerous factors contribute to increased waist circumference, primarily including genetic predisposition, dietary habits, physical activity levels, and sedentary behavior.Genetic background has gained significant attention in recent studies. Obesity exhibits familial clustering—for instance, overweight parents tend to have overweight offspring. This occurs when mutations in multiple genetic loci across different chromosomes directly or indirectly regulate fat and glucose metabolism, leading to impaired fat metabolism and progressive fat accumulation.
Unhealthy dietary habits and lack of physical activity also contribute to abdominal obesity. Additionally, sedentary habits have emerged as a significant health risk factor in recent studies, as prolonged sitting is strongly associated with increased waist circumference.Our research confirms that prolonged sitting increases the risk of diabetes and hypertension. Regular physical exercise can reduce the risk of these chronic diseases, but only if waist circumference is reduced to a healthy level. Otherwise, lifestyle improvements alone are unlikely to significantly lower the disease risks associated with abdominal obesity.
Sedentary habits and lack of physical activity are distinct concepts. Individuals with sedentary habits may still engage in adequate physical activity. For example, many occupations require prolonged sitting during work hours, such as long-distance truck drivers or office typists. While these individuals may engage in moderate exercise after work, this cannot fully offset the health hazards of prolonged daytime sitting, particularly the gradual accumulation of abdominal fat.
The aforementioned risk factors contributing to increased waist circumference are not independent; they can interact synergistically or constrain each other. For instance, an individual consuming a high-fat diet with insufficient exercise faces a significantly higher risk of obesity than someone with a high-fat diet but adequate physical activity.