Obesity is far more than a matter of appearance or a number on the scales. It is a chronic, complex and multifactorial condition that serves as a gateway to numerous other diseases. According to the World Health Organisation, obesity has tripled worldwide since 1975 and today affects more than 650 million people.

In Spain, almost 60% of the adult population is overweight or obese, figures that make this one of the most pressing public health emergencies of the twenty-first century.

What many patients do not realise is that obesity is not merely a risk factor: it is, in itself, a disease that profoundly disrupts metabolism, hormonal function, the immune system and the structure of vital organs.

Below, we review the most significant chronic diseases associated with obesity.

 

Type 2 diabetes: the most direct metabolic consequence

The relationship between obesity and type 2 diabetes is one of the most thoroughly documented in medicine. Excess fatty tissue — particularly visceral fat accumulated in the abdomen — generates a state of insulin resistance: the pancreas produces insulin, but the cells do not respond to it correctly. Over time, the pancreas becomes exhausted and blood glucose levels rise chronically.

It is estimated that between 80 and 90% of people with type 2 diabetes are overweight or obese at the time of diagnosis. The encouraging news is that a sustained weight loss of 5 to 10% can significantly improve glycaemic control and even lead to remission of diabetes in many patients.

 

Cardiovascular disease: the heart bears the burden too

Obesity places strain on the cardiovascular system in multiple ways. The heart must work harder to pump blood around a body with greater mass, which promotes the development of arterial hypertension. At the same time, the accumulation of fat in artery walls contributes to atherosclerosis, increasing the risk of myocardial infarction and stroke.

Other mechanisms involved include raised triglyceride levels, reduced HDL cholesterol (the “good” cholesterol) and the state of chronic low-grade inflammation characteristic of obesity. This cluster of abnormalities — elevated blood glucose, hypertension, dyslipidaemia and abdominal obesity — is known as metabolic syndrome and quadruples the risk of a serious cardiovascular event.

 

Sleep apnoea: when excess fat affects breathing

Obstructive sleep apnoea is one of the most underestimated complications of obesity. Excess fatty tissue in the neck and throat narrows the airways during sleep, causing pauses in breathing that can occur hundreds of times per night.

The consequences extend far beyond daytime fatigue: untreated sleep apnoea increases cardiovascular risk, disrupts glucose metabolism, causes hypertension and is associated with a higher risk of depression and cognitive decline. It is estimated that more than 70% of patients with severe obesity suffer from some degree of sleep apnoea, although in many cases it remains undiagnosed.

 

Non-alcoholic fatty liver disease: the silent epidemic

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent liver condition in Western countries and is directly linked to obesity and metabolic syndrome. In this condition, the liver accumulates fat in its cells without any significant alcohol consumption.

In a proportion of patients, fatty liver progresses to non-alcoholic steatohepatitis (NASH), a form of hepatic inflammation that can lead to fibrosis, cirrhosis and even hepatocellular carcinoma. Weight loss through lifestyle changes or bariatric treatment is currently the most effective intervention for slowing this progression.

 

Joint problems and reduced mobility

Every extra kilogram places additional strain on the weight-bearing joints, particularly the knees, hips and lumbar spine. Osteoarthritis in people with obesity not only develops earlier, but also progresses more rapidly and causes greater functional disability. Chronic pain and restricted movement, in turn, reduce physical activity, creating a vicious cycle that is difficult to break without specialist intervention.

 

Cancer: an increasingly well-evidenced link

Scientific evidence establishes a connection between obesity and at least 13 types of cancer, including colorectal, post-menopausal breast, endometrial, kidney, oesophageal, liver, pancreatic and gallbladder cancer. Several mechanisms are involved: excess insulin and growth factors, chronic inflammatory states and hormonal alterations — particularly increased oestrogen levels in post-menopausal women — promote abnormal cell proliferation.

It is estimated that between 4 and 8% of all cancers are related to obesity, a figure that could be significantly reduced with an appropriate preventive and therapeutic approach.

 

Mental health: the impact that is not always visible

Obesity also has profound consequences for psychological wellbeing. Social stigma, discrimination and body dissatisfaction contribute to the development of depression, anxiety and eating disorders. In turn, these emotional difficulties hamper adherence to treatment and can become obstacles in the weight-loss process.

A comprehensive approach to obesity must necessarily address the psychological component — not as an optional add-on, but as a central part of treatment.

 

Obesity Unit in Huelva: a comprehensive, personalised approach

Given the scale of these consequences, it is clear that obesity cannot be addressed with superficial solutions or miracle diets. It requires a rigorous diagnosis, an individualised treatment plan and long-term follow-up by specialist professionals.

At the Obesity Unit in Huelva, led by Dr.Christian Leyva, we work with an approach that encompasses everything from medical and nutritional treatment to the most advanced surgical options. The aim is to treat the disease at its root, address associated conditions and provide each patient with the tools needed to restore their health on a lasting basis.

If you have obesity or are overweight and are already experiencing any of the conditions mentioned above — or wish to prevent them — do not wait any longer to seek specialist help.

Contact the Obesity Unit in Huelva today and begin your journey towards a healthier life.