Obesity is a significant public health challenge in the UK, affecting millions of adults and children. According to NHS statistics, as of 2020, 28% of adults in England are classified as obese, and an additional 36.2% are overweight. For children, the figures are equally alarming: about 10% of reception-aged children (4-5 years) and 20% of Year 6 children (10-11 years) are obese. This rising trend has profound implications for individual health and the broader healthcare system.
What is obesity?
Obesity is defined as having an excessive amount of body fat, which increases the risk of various health problems. The most common measure of obesity is the Body Mass Index (BMI), calculated by dividing a person’s weight in kilograms by the square of their height in meters. For adults, a BMI of 30 or above is classified as obese, while a BMI between 25 and 29.9 is considered overweight. (However, this is often debated – see more below.)
Why is obesity on the rise?
Several factors contribute to the rising obesity rates in the UK:
- Sedentary lifestyles: Advances in technology and changes in work patterns have led to more sedentary lifestyles. Many jobs require prolonged periods of sitting, and leisure activities often involve screen time rather than physical activity.
- Dietary changes: The consumption of high-calorie, nutrient-poor foods have increased. Fast food, sugary drinks, and ultra-processed foods are readily available and often cheaper than healthier options.
- Socioeconomic factors: There is a direct correlation between socioeconomic status and obesity rates. Lower-income groups often have less access to healthy foods and safe areas for physical activity, meaning poverty and health inequalities are directly related to obesity.
- Lack of education: There is often a lack of awareness about healthy eating and the importance of physical activity.
Health risks associated with obesity
Obesity is not merely a cosmetic concern; it is a serious health condition that increases the risk of various other health issues, including:
- Type 2 diabetes: Excess body fat can cause the body to become resistant to insulin, leading to high blood sugar levels.
- Cardiovascular diseases: Obesity increases the risk of high blood pressure, high cholesterol, and heart disease.
- Respiratory issues: Obesity can lead to obstructive sleep apnoea and other breathing problems.
- Musculoskeletal problems: Extra weight puts additional strain on joints, leading to conditions such as osteoarthritis.
- Mental health issues: There is a strong link between obesity and mental health conditions, such as depression and anxiety.
Is BMI a reliable way to measure obesity?
In January 2025, the BBC reported that a report by global medical experts calls for redefining obesity into two categories: “clinical obesity,” for those with weight-related medical conditions, and “pre-clinical obesity,” for those at risk but otherwise healthy. This change, supported by over 50 experts, aims to move beyond reliance on body mass index (BMI) alone, which the report deems flawed for diagnosing obesity.
BMI, calculated using weight and height, is widely used to classify obesity (BMI > 30). However, it fails to distinguish between fat and muscle, or measure dangerous fat around vital organs. While BMI is useful for population-level assessments, it provides limited insight into individual health, such as organ function or specific risks.
Under the proposed framework, clinically obese patients show signs of illness, such as diabetes or heart disease, and may require treatment like weight-loss drugs or surgery. Pre-clinically obese people, who remain overweight but otherwise fit, should receive guidance to reduce future risks. This nuanced approach aims to improve diagnosis accuracy and ensure patients receive appropriate care.
Experts argue that redefining obesity is especially timely, given the increasing use of powerful weight-loss jabs such as Wegovy and Mounjaro – also known as Ozempic – often restricted to those with a BMI over 30. Critics, however, express concerns about potential budgetary constraints limiting care for pre-obese patients. The Royal College of Physicians supports the report’s call for treating obesity with the same attention to detail as other chronic diseases.
The importance of educating the public
Educating the public about the health risks of obesity and how to prevent it is crucial. Awareness campaigns can help individuals understand the importance of maintaining a healthy weight and adopting healthier lifestyles.
The role of parents in preventing childhood obesity
Parents play a pivotal role in shaping their children’s eating habits and lifestyle choices. Awareness of the risks associated with high-sugar and ultra-processed foods is essential. These foods contribute to rapid weight gain and poor nutritional intake, affecting children’s physical and mental development.
Practical advice for tackling obesity
- Speak to a GP: Consulting a GP is a crucial first step for anyone concerned about their weight. GPs can provide personalised advice and support, including referrals to weight management programmes.
- Healthy food options: Adopting a balanced diet rich in fruits, vegetables, whole grains, and lean proteins is essential. Reducing the intake of processed foods, sugary drinks, and high-calorie snacks can significantly impact weight management.
- Exercise for different ability levels: Physical activity is vital for maintaining a healthy weight. For beginners or those with limited mobility, starting with low-impact exercises such as walking, swimming, or yoga can be effective. As fitness levels improve, incorporating more intense activities like running or strength training can further aid weight loss and overall health.
- Education and support: Joining support groups or seeking the guidance of a nutritionist or dietitian can provide additional motivation and tailored advice for achieving weight loss goals.
Protect your health
Addressing obesity in the UK requires a multifaceted approach, involving public education, government intervention for those living in poverty, support from healthcare professionals, and individual commitment to healthier lifestyles. By understanding the risks associated with obesity and taking proactive steps to prevent and manage it, we can improve the overall health and wellbeing of our communities. Public health policies must also focus on creating environments that promote healthy living, ensuring access to nutritious foods and safe spaces for physical activity.
If you want to lose weight in a healthy and manageable way, make an appointment with your Primary Care 24 GP practice to discuss your options.