Obesity: A Worldwide Public Health Disaster by Prof. Anthony Barnett

10 August 2020


When I was a medical student, there were several tens of millions of people with Type 2 Diabetes worldwide. Fifty years on, the numbers are approaching half a billion and rising. Why? In a “nutshell”, exercise rates have plummeted and we eat too much! This has led to an epidemic of overweight and obesity-the biggest drivers of the condition. In the UK, obesity rates have quadrupled in a generation-over 25% of adults are obese and two-thirds are overweight. Worryingly, around 30% of children are also significantly overweight.

Obesity (particularly central obesity-excess fat in and around the abdominal organs) leads to an inflammatory condition called insulin resistance. Insulin is a pancreatic hormone vital for normal glucose (sugar) metabolism. Malfunction or reduced production causes a rise in blood glucose and development of Type 2 Diabetes.

Insulin resistance is also associated with increased risk of cardiovascular disease, certain types of cancer, dementia, cirrhosis, gynaecological problems and depression. Type 2 Diabetes itself is associated with increased risk of heart disease, stroke, amputation, kidney failure and blindness. Most worrying, we are seeing more and more cases of this type of diabetes in younger people including children and adolescents.

Obesity and its consequences could bankrupt the NHS! Worldwide societal costs are 2 trillion US dollars pa (3% of global GDP). This is more than we spend on the consequences of smoking, armed conflict and terrorism combined! Diabetes alone costs 10% of the total health care budget of the UK.

Given these frightening statistics, it is paradoxical that successive governments in the UK and elsewhere have failed to take these issues seriously. There have been notable exceptions including the successful public health campaigns in Finland which dramatically reduced deaths from cardiovascular disease. In addition, programmes such as EPODE (started in France and since adopted by many other countries-but not the UK) have helped to stem and reduce the rising tide of childhood obesity.

In the UK it has taken a viral pandemic, rather than the premature deaths and disabilities I’ve outlined, to put obesity higher up the political agenda! The much higher death rates from Covid-19 in association with obesity have provided a stark warning. So, it has taken a virus to at last embolden the government to try to properly tackle this problem.

But, don’t hold your breath! Is the Government really going to legislate against our “obesogenic” environment? We are continually bombarded by adverts for sugary/high fat/processed foods and (worse still), so are our kids. Fast food joints are around every corner; we take the car even on the shortest of trips; schools have sold off playing fields and reduced the hours of active sports (thankfully, some attempts are now being made to reverse this). We ourselves must also take some personal responsibility.

So, what can we do? I hate the term “diet”. It has such negative connotations-I’m amazed by how much money has been wasted on “fad” diets. “Balanced” food intake is required. Basically, this means consuming a high proportion of low energy foods with fewer calories per gram of weight. This includes vegetables, fruit (NOT JUICES), stews, soups, brown rice and pasta. Fibre also reduces energy density so foods like wholegrains and potato skins are great. Reasonable amounts of moderate energy foods such as grilled salmon, lean meat, lower fat cheese should also be encouraged together with significant REDUCTION in energy dense foods such as cakes, sweets, biscuits and high sugar drinks. This even includes pure fruit juices! Juicing removes fibre from the fruit and ensures the rapid absorption of fruit sugar (fructose) into the bloodstream which is then converted to fat in the liver!

What about physical activity? Taken regularly it reduces the risk of coronary heart disease, high blood pressure, stroke, type 2 diabetes, cancers of the bowel and breast, depression, osteoarthritis, liver problems and infertility. It is similarly beneficial in those with chronic conditions including type 2 diabetes, mental health disorders, high blood pressure etc. So, all to play for!

The WHO recommends: 60min of daily moderate to vigorous activity (running, jogging, brisk walking, cycling, swimming etc) together with exercises to build muscle and bone for the over 5s; for adults 150 min of moderate activity (eg. brisk walk sufficient to bring out a sweat) or 75min of vigorous activity per week (doubling this has even more health benefits) plus muscle strengthening exercises at least twice per week. For fit people over 65y, the recommendations are similar, but otherwise people should be “…as physically active as their abilities and conditions allow.” Discuss with your health care professional what’s best for you.

To reduce obesity rates and its health consequences will require significant public health engagement including information and educational programmes, involvement of families and schools, and support from local and central government. Changes to food labelling may be necessary, and legislation to ensure the food industry reduces sugar content, changes to advertising and supermarket positioning of “unhealthy” products and extension of the “sugar tax”. Promotion of physical activity will be vital. Most important will be prevention of obesity in young people. This will require “buy-in” from them and their families with support from schools, local and central government and indeed the food industry. It won’t be easy, but it can be done as evidenced by successful programmes in other parts of the world.

To quote from a recent editorial in the Lancet: “The primary risk factor for development of type 2 diabetes across all ages is obesity, which is largely preventable……..If the growing prevalence of obesity and type 2 diabetes in youth is accepted as the new normal, society will have grossly failed the next generation.” (Lancet, 2018: 392:2325).

The alternative is to do nothing, but the consequences of inaction are too terrible to contemplate.