Obesity crisis is a national and global emergency, contributing to heart attacks.
Excess body fat is a ticking health time bomb and not just a body image problem. The obesity crisis is a national and global emergency, contributing to heart attacks and premature death, increased health costs, decreased productivity and fertility, in an unhealthy population, and a depressed economy.
BODY FAT: It functions as an energy store, insulation against cold, a cushion around vital organs, and produces certain hormones and signalling molecules (ligands). Leptin, a hormone secreted by fat cells, signals the brain to suppress hunger and increase calorie (energy) expenditure. Adiponectin, another hormone secreted by fat cells, helps regulate blood sugar levels. Fat cells convert precursors of sex hormones (Estrogen, Testosterone) into active forms that influence body fat distribution, and contribute to male hormone (Testosterone) production in women. Fat cells also release signalling molecules that decrease insulin sensitivity and increase inflammation. Fat is categorised by location as subcutaneous fat (under the skin) and visceral fat (around the internal organs). Subcutaneous fat provides insulation, visceral fat cushions the organs, and both store and release energy. Visceral fat contributes more to health risks. Functionally, most of the body fat is white fat. Brown (due to higher iron content) fat is present in infancy and diminishes with age, and is located primarily in the upper back. It keeps the body warm by continuously releasing energy in cold conditions (non-shivering thermogenesis), protects infants from hypothermia, and is linked to better health.
CONTRIBUTING FACTORS: Excess intake of calorie-rich food like processed snacks (even by the under-nourished), sedentary lifestyle, high stress levels, and hormonal and genetic factors contribute to excess body fat. Elevated cortisol (stress hormone) levels, low thyroid hormone levels, declining sex hormone levels with age and menopause, contribute to weight gain. Ghrelin is a stomach hormone that stimulates appetite and contributes to weight gain, especially in obesity or during periods of restricted eating. The brain’s impaired response to satiety hormone leptin (leptin resistance) leads to increased appetite and more body fat.
SIGNALING CONSEQUENCES: Signalling molecules (ligands) transmit information between cells and are crucial in coordinating responses, processing stimuli, and maintaining equilibrium (homeostasis). Excess body fat, particularly visceral fat, releases pro-inflammatory cytokines (signalling molecules). This inflammation damages blood vessels, leading to impaired blood flow and leading to accelerated aging (by shortening of telomere, the protective caps on the ends of chromosomes), decreased body functional capacity, substantial disability, cognitive decline, dementia, and chronic diseases of vital organs (heart, liver, kidneys, etc.), increased risk of heart disease, stroke, and premature death. Excess fat can increase the production of unstable free radicals (oxidative stress) that damage tissues, cells, DNA, proteins, and lipids, accelerating aging. Excess body fat leads to high blood pressure (hypertension) by increased production of inflammatory substances and hormones that disrupt blood pressure regulation, and by straining the heart. Excess fat in the liver (fatty liver) leads to liver damage, scarring, cirrhosis, and liver failure. Inflammation, oxidative stress, and excess fat in bone marrow increase bone resorption (breakdown) and reduce bone formation, increasing the risk of fractures.
PHYSICAL CONSEQUENCES: Excess body weight stresses joints, increasing the risk of osteoarthritis, reducing mobility, and quality of life. Excess fat in and around the neck can narrow airways and increase the risk of breathlessness and sleep apnoea. Excess fat can affect the digestive system, leading to bloating, gas, loose stools, and acid reflux (GERD). Poor body image increases the risk of depression and mood disorders. Tight skin folds are prone to infections and rashes.
HORMONAL CONSEQUENCES: Excess body fat, particularly visceral fat, can cause hormonal imbalances, affecting metabolism, insulin function, fertility, pregnancy, and overall well-being. Less cell response to Insulin (Insulin Resistance) and metabolic dysfunction (Metabolic syndrome) increase the risk of type 2 diabetes, heart disease, and stroke. A decreased sex hormone level reduces muscle mass, bone density, and libido. Decreased semen quality, ovulation, and success rates of assisted reproductive technologies in the obese reduce fertility. Sex hormonal disorders in obese women (Polycystic Ovary Disease or Syndrome) are characterized by irregular periods, infertility, and increased levels of male hormones (androgens), causing hirsutism (excessive hair growth). Growth hormone deficiency reduces growth in children, metabolism, and muscle mass.
IMMUNOLOGICAL CONSEQUENCES: Excess body fat, causes premature thymus (produces T immune cells) involution and significant immunological dysfunction leading to increased incidence, severity and complications of infections, altered immune responses to vaccines, reduced efficacy of immunotherapy and other treatments, and potentially increased risk of several cancers, including endometrial, breast, and colon cancer.
MEASURING BODY FAT: Body mass index (BMI) chart estimates your body fat based on your height and weight and indicates status as healthy (18.5 to 24.9), overweight (25 to 29.9), obese (30 to 34.9), morbidly obese (35 to 39.9), and super obese (40 or higher). It is inaccurate for those with higher BMI due to greater muscle mass, larger bones, or short stature. The waist-hip ratio (WHR) is a simple calculation that measures body fat distribution by dividing your waist circumference by your hip circumference, and is useful in individuals with a high BMI. A higher WHR (over 0.85 for women and 1.0 for men) suggests increased risk of cardiovascular disease, type 2 diabetes, and other health problems mentioned above. The bioelectrical impedance analysis (BIA) method and skinfold pinch test are less accurate. There are numerous other complicated methods of measuring body fat.
MANAGEMENT: Undernutrition is treated with supplements, and over-nutrition is treated with diet and exercise. Medication or bariatric surgery may be required if exercise and calorie restriction are inadequate. Several diabetes medications and many recent drugs induce fat loss. Their long-term efficacy and complications are not yet known.
Excess body fat accelerates aging, reduces functional capacity, and causes chronic diseases like diabetes, cardiovascular disease, certain cancers, reproductive issues, and sudden premature death. A balanced diet rich in fruits, vegetables, sprouts, lean proteins, and healthy fats, avoiding sugary drinks, processed foods, and saturated fats, combined with adequate physical activity, exercise, sleep, and stress management, helps reduce body fat and improve overall health.
Dr. P.S.Venkatesh Rao is a Consultant Endocrine, Breast & Laparoscopic Surgeon, Bengaluru.
