In spring 2023, Obesity Action Scotland published a blog on a drug that was becoming available for the treatment of obesity, particularly for people with diabetes: If semaglutide is the answer, what’s the question? However, almost two years later, we are not much nearer to finding that question.
We do have the answers to some issues. Yes, the drug can assist some individuals with overweight in achieving weight loss and it can relieve some people of their diabetes. But we do not know whether these benefits persist long term.
Semaglutide can reduce people’s future risk of secondary diseases such as cardiovascular events (2). Can it also prevent a range of other diseases (such as cancers associated with obesity)? Perhaps.
There is no evidence that semaglutide and similar drugs prevent obesity in normal use – to find out, we would have to see research on populations of healthy weight, on people with and without diabetes. The drugs can treat obesity and overweight that already exists – that at best averts the problem worsening, currently affordable for a fortunate few. It’s perhaps good to recall what types of prevention we are thinking about, drawing on Public Health Scotland’s definitions:
Semaglutide and similar drugs will only seek to address secondary and tertiary prevention. It will not make a large dent in the obesity epidemic we have now. A targeted programme that reaches and delivers for people in proportion to their need would require very, very careful design. In reality, we will probably see over-treatment in affluent groups, and under-treatment in deprived groups, making inequalities worse, and many people will stop taking the drug, often due to its side-effects.
Furthermore, semaglutide will certainly not control the epidemic of childhood obesity now hitting the UK, and widespread use will add additional pressure to the NHS, which is already under severe financial strain (4).
Primary prevention of obesity on the other hand would mean we ‘stop the problems from happening’ in the first place. How do we do that? With a strategy that changes fundamentally our approach to food and drink. That plan should be supported by an effective strategy to tackle poverty and inequalities in health, so that the people who need the most support are likely to get it. That’s complicated; it requires a system-wide change and coordinated efforts not just within the health service, but across different sectors, involving more than just the people directly affected. The core ambition is to invest in creating healthier food environments for everyone. Key components include promoting healthy local produce, stimulating local enterprise, improving productivity, making healthy food options affordable and sidelining the distractions of unhealthy food and its marketing (5, 6). By connecting up all of these elements, the return on investment will be much higher than the tertiary prevention alternative.
So, could drugs, mainly injected although with new options for pills, do the heavy lifting to remove the burden of obesity? No, they could not. They will help some people who already have health problems, provided there is a fair and equitable way to reach potential patients. They will not help everyone who takes the drug, and any effect will only last as long as they stay on treatment. Semaglutide injections will not protect young children, where levels of overweight are already high; the Scottish Government wants to halve childrens’ obesity levels in the next 6 years (7). Semaglutide won’t prevent obesity for the Scottish population as a whole (two thirds of whom are overweight or living with obesity), and it won’t stop people regaining weight after they stop taking the drugs.
We need a much wider change in our national approach to food and drink – how we prepare, supply, buy and consume it, and how we require food retailers to put a healthy choice in front of consumers.
If the questions are:
How do we tackle our epidemic of obesity?
How do we design a pathway toward our target to reduce childhood obesity?
How do we tackle the underlying inequalities?
What would it take to substantially reduce the burden of overweight and obesity on the NHS?
How do we create an environment where having a healthy diet and weight is nigh-on inevitable - the opposite of what is true of the current situation?
…then drugs will not sort our problem.
Blog written by Dr Andrew Fraser, Steering Group Chair, Prof Simon Capewell, Steering Group Member, and Dr Shoba John, Head of Obesity Action Scotland.
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