In Spain, 76% of people with obesity say excess weight affects their health, but only 56% recognise that they have the disease. The preliminary results of the Razones de Peso survey show how far concern can be from personal recognition. The World Health Organization says more than 1 billion people were living with obesity worldwide in 2022.
The American Medical Association first classified obesity as a disease in 2013 and reaffirmed that position in 2023.
Lilly promoted the survey with support from the market research company IPSOS. It included 200 primary care doctors and 1,700 people with a body mass index of at least 30 kg/m², the threshold used to classify obesity. Sixty per cent of participants recognise obesity as a disease. Only 56% say they live with it.
The results also challenge the idea that weight can be managed with a simple instruction to eat less and move more. Only 38% of people with obesity describe it as a chronic disease that is difficult to control through lifestyle changes alone. Just 33% identify biological factors as the basic cause, and only 26% know that the body can activate metabolic mechanisms that make weight loss harder.
The European Observatory on Health Economics, attributed to the Organisation for Economic Co-operation and Development Health Economics Observatory, reports that the prevalence of overweight and obesity among adults in Europe has risen substantially since 1990, with obesity increasing by more than 75%. That helps explain why the condition is increasingly discussed as a population-level health and economic issue rather than an individual failure.
That limited understanding affects treatment.
Obesity involves genetic and endocrine factors. Environmental conditions also matter, including an obesogenic environment and endocrine disruptors. Stress, disrupted sleep, behavioural patterns and sociocultural influences can affect energy balance. Fat tissue can then grow beyond the body's storage capacity, triggering dysfunction and inflammation across organs and systems.
The WHO describes obesity as a chronic, complex condition. It links obesity to cardiovascular disease, diabetes and some cancers.
Spanish summaries of recent estimates put the economic cost of overweight and obesity at 19.6 billion euros a year, about 1.2% of Spain's GDP. The same summaries estimate that obesity affects about 14.9% of Spanish adults and 7.1% of children.
Primary care doctors see the problem more clearly than many patients do. They rank obesity alongside type 2 diabetes and high blood pressure in terms of treatment importance. Forty per cent say it is very difficult for a patient to control obesity through lifestyle changes alone, while another 86% equate it with other chronic diseases.
The approach aligns with the European Association for the Study of Obesity's description of obesity as a chronic, relapsing disease and a major cardiometabolic risk factor. The association says it should be identified earlier.
Patients most often connect obesity with high cholesterol and high blood pressure, at 59% each. Type 2 diabetes follows at 52%, while joint and mobility problems reach 51%.
When asked about the most serious consequences, 27% name myocardial infarction. Stroke comes next at 12%, followed by certain cancers at 11%. For 40% of doctors, the basic benefit of weight loss is better control of other conditions linked to obesity.
The medical effects extend beyond weight itself. Cardiologist José Abellán says obesity is associated with more than 200 diseases and that cardiovascular complications can be frequent and potentially fatal. In his view, doctors should treat excess weight as the primary disease, rather than wait for another complication to appear.
More than half of the doctors surveyed believe patients do not see obesity as a serious problem requiring medical help. Doctors say they discussed excess weight with 66% of their patients. In 68% of those conversations, the immediate goal was to improve another complication that had already appeared.
Federico Luis of the Asociación Nacional de Personas que Viven con Obesidad, or ANPO, says fear of judgement can keep people from seeking care. So can the expectation of hearing only lifestyle advice.
The figures point to a communication problem as well as a knowledge gap. Sixty per cent of respondents recognise obesity as a disease, yet only 56% of people affected identify it in themselves. Doctors also often raise the issue only after related harm has appeared.
Lilly executive Teresa Millán says primary care doctors and patients should discuss obesity and excess weight earlier. She argues that these conversations should receive the same priority as those about other chronic diseases.
The survey challenges the idea that obesity comes down to personal discipline. Recognition needs to come earlier. Medical care cannot stop at advice about habits.
Obesity is chronic, complex, progressive and multifactorial. Treating it as such is the starting point for earlier care.
