Interview | Weight loss drugs changing way we look at obesity: Dr Ambrish Mithal

Dr Ambrish Mithal’s book— The Weight Loss Revolution— that’s released on Wednesday provides a detailed insight into these weight management drugs and how to use them, in the Indian context

Mounjaro and Wegovy have hit the market, and with this the global weight loss revolution has come to India. Dr Ambrish Mithal’s book— The Weight Loss Revolution— that’s released on Wednesday provides a detailed insight into these weight management drugs and how to use them, in the Indian context. Speaking to HT about the book, Dr Mithal— a renowned endocrinologist— highlights the need for generating awareness among masses about the role of these drugs, who are the right candidates for it, and the side-effects— even though mild— that one is likely to experience.

Does it look like we have reached the stage where no less than a revolution is needed for weight-loss?

Excess weight is a precursor to most modern metabolic disorders but unfortunately the tools to help us lose weight have been very limited. It’s been more or less a disaster actually except for extreme cases when you went for surgery, which was utilised by a very small proportion of the population. You really didn’t have much by way of drugs that help you lose weight. So, the reason I called it the weight loss revolution was that to address the modern metabolic sort of issues, we need to address weight. And for the first time, this whole crop of drugs that is coming out now, they are changing the way we look at it because they provide us the ability to actually help reduce excess fat and, therefore, reduce all the consequences of excess fat. I think it’s a revolution because before this, you were struggling with much lower degrees of weight-loss.

Yes, a majority of people look at weight as a cosmetic problem. And even now I am surprised every other day when I explain the relationship between something as obvious as weight and diabetes, many patients are unaware of the association. Even if they do understand the relationship between health and weight, sometimes that is not enough motivation for them to dive deep into obesity. People get motivated much easier by cosmetic issues than health issues.

How is the current class of weight-loss drugs different from its predecessors?

This is the class of drugs called GLP1 drugs, and this class we have been using now for almost two decades. These were developed for treating diabetes, and the initial ones worked very well for diabetes with additional benefits of weight-loss. Research in this area continued— the molecule kept on getting modified— and what made the semaglutide standout was the degree of fat-loss achieved, which was remarkable. It hit 15-16% of the baseline weight that had never been seen before. This is the same class of drugs— GLP1— but the incremental improvements were such that the degree of weight-loss one could achieve was substantially greater. Semaglutide and another molecule called tirzepatide (mounjaro)— a dual GIP and GLP-1 receptor agonist— have crossed the line for us in terms of efficacy and broken the barrier of treating obesity.

What about the side-effects of these drugs?

Anything that has effects will have side-effects. Fortunately, these drugs don’t seem to have any sinister long-term side-effects, but yes, tolerability can be an issue with symptoms such as nausea, vomiting, constipation, or diarrhoea that in selected patients— a small proportion— can be troublesome. But these are transient effects. Some other long-term effects related to the eye etc. are still in the realm of research.

Can the weight come back later, if one stops taking these drugs?

In severely obese patients and patients with disorders linked with obesity, it certainly is going to be a life-long therapy. There, however, is a huge chunk of people who are in-between and we don’t know yet whether all of them should be on life-long therapy or not. There’s likely to be a period of aggressive weight-loss and then a period of weight maintenance that would probably require much lower doses. These drugs need to be a part of weight management programme and not a standalone treatment for obesity. The weight can come back after stopping these drugs, if you haven’t tailored your lifestyle significantly.