While it is well-known that Obesity increases the risk of heart disease, Stroke, Diabetes, and some cancers, knowledge about its effect on bone and joint health amongst the public is limited.
Obesity is a condition in which a person has an excessive amount of body fat or an unhealthy body fat distribution. Not only does Obesity make physical movement challenging, but it also raises the risk for numerous health complications. In addition, excess body fat puts strain on the joints and multiple organs in the body. It also causes various changes in hormones and metabolism, thereby increasing inflammation in the body.
The World Health Organization (WHO) defines Obesity using the Body Mass Index (BMI), which is a ratio of one’s body weight in kilograms to the square of their height in metres (kg/m2). An individual is classified as being ‘overweight’ if their BMI is ≥ 25 and ‘obese’ if their BMI is ≥ 30. According to WHO’s 2016 statistics, 39 per cent adults worldwide were overweight, and 13 per cent were obese. The scourge of obesity has tripled since 1975.
In the past two or three decades, there has been a drastic change in dietary habits, including increased consumption of high fat and sugar-rich foods on the one hand and decreased physical activity on the other hand. These two factors have led to Obesity becoming a major health issue around the globe. While it is well-known that Obesity increases the risk of heart disease, Stroke, Diabetes, and some cancers, knowledge about its effect on bone and joint health amongst the public is limited.
Effects on Joint Health:
Osteoarthritis (OA) and Rheumatoid Arthritis (RA) are the two most familiar conditions affecting the joints. Osteoarthritis is characterised by joint damage due to wear and tear, while Rheumatoid Arthritis is an autoimmune disease where the body’s immune system attacks its joints and other tissues. Obesity is linked to both OA and RA.
Obesity and Osteoarthritis
The effect of Obesity on joint degradation is two-fold, including physical and chemical. The mechanical overload due to obesity increases the risk of cartilage degeneration, especially in the weight-bearing joints like knees and hips (physical effect). Additionally, the fat tissue in the body produces certain chemicals, which also results in cartilage damage (chemical effect). Research has shown that obese people have an increased risk of OA affecting the knees, hips, wrists, and hand joints.
Obesity and Rheumatoid Arthritis:
In Rheumatoid Arthritis, the damage to the body’s joints and tissues is mediated by cytokines. The fat tissue in obese individuals also produces and releases cytokines which causes inflammation in the joints. Obesity increases the risk of RA, reduces the chance of disease remission, and adversely affects treatment outcomes.
