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What Obesity Policies Do We Need?

Earlier this week, I presented at a high-level UK Health Policy Workshop on how I would shape policies to deal with the obesity issue.

My suggestions can essentially be summarised as follows:

  1. All relevant policies need to acknowledge that obesity management requires the same approach as any other chronic disease. 
  2. The biological nature of the body’s defense against weight loss dictates the need for treatments that address the biology and don’t just rely on education, motivation, and willpower. 
  3. Managing obesity needs to become first-line treatment for all patients presenting with any obesity related comorbidity.
  4. Obesity management can be funded by progressively diverting funds from treating obesity complication and comorbidities to treating obesity itself.
  5. Basic competencies in obesity management need to be a mandatory requirement in all medical licensing exams. 

Whether or not these suggestions find their way into health policies in the UK or elsewehere remains to be seen, but I certainly see no alternative to implementing such policies if we are ever to make a dent in the obesity crisis that is clearly affecting every health care system around the world. 

@DrSharma, MD
Berlin, D


Guest Post: Racial Diversity in Obesity Research and Practice

Fatima Cody Stanford, MD

Today’s guest post comes from my dear colleague Fatima Cody Stanford, MD, Associate Professor of Medicine and Pediatrics, Harvard Medical School. 

Particularly in the aftermath of the murder of George Floyd here in the United States, there has been greater attention to racial and ethnic diversity in every domain of human life. His brutal murder during the COVID-19 pandemic set the stage for those to consider the prominence of disparities and how they contribute to differences in health, quality of life, morbidity, and mortality- just to name a few. So now, more than any time since the 1960 civil rights movement catalyzed by individuals such as Martin Luther King Jr., we recognize that racial and ethnic diversity matters. 

But why does racial and ethnic diversity matter in the field of obesity? Why should we care?

The answer is quite simple. Disproportionately, individuals from racial and ethnic minority groups bear the brunt of the burden of obesity. As a Black woman obesity medicine physician-scientist, I can definitely say that the disproportionate burden of obesity in the Black community – particularly amongst those that are the descendants of the enslaved like myself here in the United States, brought me to this field. each and every day in this work I realize the importance of the focus on this issue. Yet, my daily focus on racial and ethnic diversity in the field is not genuinely shared by many of my colleagues. Hence as we seek to improve the care for persons with obesity, we fall short of being able to do so. 

How is this you might ask? Let’s take a pause and look at clinical trials that are performed around the world for anti-obesity pharmacotherapy. You don’t have to do a deep dive to recognize that the subjects included in those trials disproportionately do not reflect the diverse tapestry of individuals who are impacted by the disease of obesity. As we peruse the prominent publications in the top peer reviewed journals throughout the world, you also don’t see many authors that reflect racial and ethnic diversity.

So, how are we going to treat a disease when both the patients, physicians, and other healthcare providers that care for these patients don’t reflect the diversity of the population? How can we extrapolate data and presume it will apply broadly to a population that is underrepresented? We can’t. So we continue to fail. Yet, no one really seems to care.

You might push back at me for that. I am someone who eats, lives, and breathes as a Black woman in this world. Saying that you care and speaking about the issue of racial and ethnic diversity in obesity without taking any true steps to improve the status quo means you’re complicit in the lack of progress. 

So what steps can we take to make a difference?

Here are my personal thoughts of initial steps we can take to change the narrative and actually make a difference in persons from racially and ethnically diverse backgrounds in obesity.

1. Recognize the burden of obesity and racial and ethnic minority communities throughout the world and recognize that it’s prevalence stems from multiple biologic, social, economic, and other factors.

2. Empower individuals from racial and ethnic minority communities to pursue careers and work in obesity as this diversity in the workforce will lead to better quality of care for this patient population.

3. Ensure that trials of all kind: lifestyle, pharmacotherapy, surgical interventions have a diverse cohort of subjects so that the results can be extrapolated to all. 

4. Be a true ally. Don’t just talk about the issue of racial and ethnic diversity in obesity. Do the work. 

5. If you have no idea where to start, seek out those of us that do to assist you in this work.

The time for us to act is now. Let’s stop talking about the problem and be a part of the solution. You can start with you today.

Fatima Cody Stanford, MD
Boston, USA

About the author: Fatima Cody Stanford MD MPH MPA MBA FAAP FACP FAHA FAMWA FTOS is an Associate Professor of Medicine and Pediatrics who practices and teaches at Massachusetts General Hospital (MGH)/ Harvard Medical School (HMS) as one of the first fellowship-trained obesity medicine physicians worldwide. She is one of the most highly cited obesity medicine physician-scientists with over 150 peer-reviewed publications.


Guest Post: Obesidades Mexico

Verónica Vázquez Velázquez, PhD,

Today’s guest post comes from my Mexican friend and colleague, Verónica Vázquez Velázquez, PhD, Co-founder and President of Obesidades.

Is obesity a single disease or are they several diseases with common clinical manifestations? Science is trying to answer this, but every one living with obesity has their personal definition. 

In Mexico, more than 80 million children, teenagers and adults live with overweight or obesity (55% of children from 0 to 11 years, 44% of teenagers and 74% of adults, from a total of 126 million inhabitants). This means that most Mexican people live with abnormal or excessive body fat that may impair their health. 

For some, obesity is merely living in a large body, but for others, this is a disease that leads to other diseases and has alienated us from our work, social and love lives. For many, this also means living under the critical and biased eye of physicians, relatives, friends or strangers, who think that “this is our fault”. In reality, obesity results from a series of factors, some that can be controlled/treated and others that we have not chosen (such as biology, genetics and the environment).

I remember talking with Dr Sharma in July 2020 and can´t forget his words: “What makes you angry about what is happening in Mexico with obesity? What can you do about it? Whatever it is, make it important and manageable. First, get together friends who think alike and understand obesity. Then, little by little, you will add people to spread knowledge and advocate for change. If you feel passionate about it, just do it. It does not have be perfect, it just has to be good”. 

This is why we founded Obesidades (Spanish plural for obesity), to give voice to those interested in understanding and addressing obesity. 

We are a non-profit organization incorporated in Mexico in 2020 by a psychologist/patient in treatment, a bariatric surgeon and a physician/patient in treatment. Our goal is to create a community that includes people living with obesity, health professionals, organizations and authorities, all joined together for changing the narrative around obesity and its treatment.

Primary prevention is important, but clearly many of us will, at some point, require access to health services offering an individualized biopsychosocial approach, incorporating early diagnosis and evidence-based treatments that includes strategies to sustain the treatment in the long term. 

All of this may seem complicated. Nonetheless, we can start by changing the narrative around obesity and its treatment, as we now know how harmful weight bias, negative stereotypes, stigma, and discrimination against people living with obesity really are. 

The new obesity narrative should include awareness, evidence-based education, training for health professionals based on an empathetic and compassionate approach and should place the person living with obesity right at its core.

What have we achieved?

To date, our Obesidades community includes more than 10,000 healthcare professionals, people living with obesity, family members, friends and people interested in looking at obesity from a different perspective. We work through committees, social networks, and discussion groups to put the topic on the table and offer evidence-based information in Spanish, so that we can join forces.

We began a national multi-center study in Mexico on attitudes, knowledge and stigma among the general population and healthcare professionals. We launched an awareness campaign named “Weight stories”, through which we emphasize the damage of weight stigma, and we make people aware that obesity is a disease impacting each person in a different way. Also, we created a treatment finder (with healthcare professionals, public and private hospitals and clinics) to help people living with obesity find a safe, ethical and professional place to initiate or continue treatment.

Where are we going?

Our work has begun, and we will not stop until we achieve our goals, i.e.:

1. Obesity is recognized and treated as a chronic and multi-factorial disease. Accepting this truth is not easy, but we want to be there for those in doubt, with evidence-based information, provided in a simple and compassionate way.

2. Healthcare professionals are trained for obesity management. To reduce weight stigma in the medical practice, so that every Mexican is offered adequate treatment.

3. Stigma and discrimination are recognized as harmful factors that need to be eliminated. Many people are not aware of the damage of their negative comments, jokes, and actions. If there is someone not sure about how to help, this may be a good start.

4. Verbal and visual narrative is changed. Educate the general population, authorities and associations about the use of people-first language, as well as including fair and dignified images of people living with overweight.

5. Access is offered to evidence-based and long-term treatment. If we get rid of weight and obesity treatment stigma and negative assumptions, we may reduce the time it takes before talking to a health professional about our weight and health, thereby preventing us from getting sicker every day.

Although only two years have elapsed, there is already much more to see from Obesidades. This is a good fight, a good cause, and a good team. We can be a bridge and an ally to connect different countries from Latin America, Hispanic people who are also struggling with access to more knowledge and better treatments.

We are thankful for the pathway laid out by the World Obesity Federation, Obesity Canada, ConscienHealth, Obesity Action Coalition, Global Obesity Patient Alliance, Obesity UK, European Association for the Study of Obesity, European Coalition for People living with Obesity, and Asociación Bariátrica Hispalis, all of whom have taught us to never give up, no matter how difficult the path may look.

“We with obesity live in a world that reminds us of it. We know the impact this has on our health. Many of us try to take care of it on a daily basis, but sometimes the disease is stronger than us, it defeats our strategies, our will. That is why we deserve empathy and treatment” Cristina, 47 years old.

Verónica Vázquez Velázquez, PhD
Mexico City, Mexico

About the author: Verónica Vázquez Velázquez, PhD in Psychology, is president of Obesidades. She is also a clinical psychologist at the Obesity and Eating Disorders Clinic of the National Institute of Medical Sciences and Nutrition Salvador Zubirán (INCMNSZ) in Mexico since 2000. Professor at different universities, she has published more than 45 scientific papers and book chapters and has co-edited the “Obesities Manual: An opportunity to improve the health of your patient”. She has 21 years of clinical experience with patients living with obesity and their families, in the creation of psychoeducational interventions, in the training of healthcare professionals and in clinical research. Email:


Guest Post: Family Doctors and Obesity Management

Dr. Michael Crotty

Today’s Guest Post comes from my colleague Michael Crotty, MD, a family doctor in Dublin, Ireland.

I believe we are on the cusp of a new dawn where the vast majority of bariatric care will be provided in primary care with family physicians taking a leading role.

Obesity is a chronic, progressive disease that impacts every organ and system in the human body. It requires an individualised, bio-psycho-social approach which incorporates screening, early diagnosis and evidence based treatment. We must shift away from solely focusing on primary prevention to also provide treatment and support to those living with overweight and obesity. This is in addition to the ongoing management of the potential medical complications and co-morbidities. There is, undoubtably, work to be done to change the narrative around obesity in society. We must continue to reduce the weight bias and stigma that persists in healthcare and primary care is no different.

As family doctors, we are perfectly positioned to support patients who live with obesity. If we are adequately resourced, we have the capacity to see the large volumes of patients for whom excess weight may affect health. Primary care is not only a more convenient setting for our patients but it also offers significant savings from a healthcare economics perspective when compared to hospital based care. In many countries, primary care clinicians have invested heavily in healthcare informatics/IT and have been at the forefront of adopting hybrid models of care. These advancements have been realised on a day to day basis during the COVID19 pandemic. There is an opportunity to offer a blend of traditional, in-person and virtual consultations to patients living with obesity. The advantages offered are immense and can potentially remove some of the barriers to care that have existed in the past.

As GPs, we know our patients in the context of their family and their community. We treat them across their lifespan. This provides an opportunity to screen those at higher risk ( with knowledge of family history, medical history and medications etc) and to facilitate early intervention. We are skilled in managing chronic diseases and offer the continuity of care and frequent review that is needed to manage a long term, progressive medical issue like obesity. We are innovators and can be at the forefront of adopting new treatments as they become available.

We are experts in communication, behavioural support and brief intervention – the foundation of medical weight management. We are the last true generalists. We do not view our patients living in a vacuum or through the narrow lens of one disease but see them as individuals with unique experiences, skills and challenges. We spend our day managing multi-morbidity. What is best for the

heart may not suit the kidneys, what is best for mental health may not be best for weight – it is up to us to integrate these competing challenges and collaborate with our patients to find what is most appropriate and acceptable to them. Putting the person at the centre of the decision making process is vital and we do this every day in our practice. Although we are directed by guidelines and evidence, we must adjust our treatment plan based on the bespoke needs and values of our patient. We are already treating people for weight related complications and co-morbidities which will undoubtably be lessened if we can also manage the underlying cause.

In primary care we spend our day constantly shifting gears, (in my case this is assuming I have had enough coffee) and transition between discussions about psychological, functional or metabolic health. This is one of the most vital skills when managing a medical condition that can affect every facet of health. Over many years treating our patients, we develop a rapport and trust. This helps us appreciate when it may be acceptable, with permission, to start a conversation about weight. If they feel a discussion is not appropriate at that time, we know that we will certainly meet them again and have made it clear that we are available to help.

It is implausible to think of every patient with hypertension or asthma being seen by a specialist for treatment. Our hospital system does not have the capacity. The skills of my esteemed colleagues are better applied to patients living with the most complex and severe illnesses. There will always be a place for specialist multidisciplinary medical and surgical bariatric care but why must patients languish on long waiting lists developing more severe complications when we can start treatment and intervene earlier in primary care – Obesity should be treated like all other chronic diseases. With safe, effective treatments and a shift in our approach towards pharmacotherapy with an adjunct of behavioural intervention we will be less reliant on the conventional MDT approach. We are already prescribing identical treatments for other indications with great success.

With adequate funding for treatments, training and an appropriate referral pathway there is an army of healthcare practitioners in primary care who are sufficiently caffeinated, ready, willing and able to treat the chronic disease of obesity.

Michael Crotty, MD
Dublin, IE

About the author: Dr Michael Crotty is a General Practitioner who specialises in Bariatric Medicine. He is a member of the Clinical Advisory Group of the Irish National Clinical Programme for Obesity and co-chair of the Adult Weight Management Subgroup. He was awarded a SCOPE National Fellowship by the World Obesity Federation. Michael is the co-founder and clinical lead of the “My Best Weight” medical weight management clinic in Dublin, Ireland. 


Guest Post: My Journey With Obesity Medicine in Clinical Practice, Academia and Industry

Today’s guest post comes from my friend and colleague Abd Tahrani MD, PhD, International Medical Vice President in Global Obesity Drug Development at Novo Nordisk.

My interest in obesity was sparked as a medical student. I remember being fascinated by three diseases: obstructive sleep apnoea, non-alcoholic fatty liver disease (NAFLD) and polycystic ovaries syndrome (PCOS). Clearly, obesity and disturbances in weight regulation (as well as abnormalities in autonomic function but that’s a separate story) play an important role in these diseases. But, at the time, there was no training in obesity in my medical school, which sadly is still uncommon globally today.

 My interest in obesity was reignited when I started my specialist training in diabetes and endocrinology. It was clear to me that there was a huge unmet need in the field of obesity. The burden of the disease was huge, access to health care for patients with obesity was challenging, treatment options were limited, stigma, prejudice and myths were quite common in the wider society as well as amongst health care professionals, payers and policy makers, and relatively low interest amongst my fellow trainees to specialise in obesity. 

Many of my colleagues felt that I was “mad” to choose obesity. Their negative impressions were driven by the perception that obesity was a “hard” speciality where achieving a successful treatment outcome is challenging and that the “customers” are unlikely to be happy with the results. 

For me, the challenge to improve health care delivery, treatment outcomes and patients satisfaction was a major driver. Also, my colleagues often cited the lack of effective pharmacotherapy as a reason to avoid specialising in obesity. 

After deciding that obesity medicine was a career for me, I faced the reality that there was no clear training path to become an obesity specialist in the UK. Hence, I had to build my own clinical training program alongside my academic research training. This enthused me to work with the appropriate societies and organisations in the UK to improve obesity training and to establish the first dedicated course to train diabetes and endocrinology trainees in obesity medicine in the UK. 

However, obesity medicine can be practiced by a wide range of health care professionals beyond diabetes and endocrinology. Hence, it is important to establish the appropriate education resources across multiple disciplines, especially primary care. 

In my years of practicing obesity medicine, I found working with patients in the clinics most enjoyable. It was rewarding to work with patients and their families to improve their health and quality of life and achieve their treatment aims. I found that the negative impressions about obesity as a speciality were unfounded. In addition, working with a large multidisciplinary team allowed for great opportunities for learning and teaching.

Working in the obesity field taught me that patients living with obesity were misunderstood, stigmatised and treated unfairly by the health care system. 

Health care professionals know very little about the pathogenesis and management of this disease. Many patients report unsatisfactory interactions with the health care system over years if not decades. Access to treatment is limited. Funders and policy makers generally perceive obesity as a “self-inflicted” condition and do not prioritise obesity care. 

Moreover, many funded obesity treatments for obesity are based on inadequate short-term interventions rather than a long-term chronic disease treatment model. 

A major unmet need in the field of obesity is the lack of safe and effective pharmacotherapy. Given that better medications for obesity could transform the field of obesity medicine, beyond what I could achieve in academia, in July 2021, I decided to join Novo Nordisk’s global obesity clinical drug development team to play a role in shaping the future pharmacological treatments in obesity, while ensuring that patients’ needs are addressed and to help remove the current barriers to health care delivery. 

But there were also personal reasons for deciding to join industry. One of these was that I wanted a role that offered new challenges and wider opportunities for career progression than my academic career at the time. 

Changing career tracks come with opportunities and challenges, professionally as well as socially (such as moving with family to a new country). However, the industry is used to support such moves both on the professional and social level and this eased the process significantly. 

Also, working with a large team of experts who have deep understanding of obesity and its impact on patients across all the stages of drug development creates a unique environment focussed on training, development and innovation. 

As it turns out a lot of my academic, clinical, policy and health economic skills were very handy in my new role in industry. My current role can perhaps best be summarised by being the internal “KoL” supporting and leading the obesity team. 

Working with a big company also offers extensive opportunities for training and self-development in a wide range of fields and skills. I have learnt about the value chain and how the different departments from early discovery, to drug development, regulatory, data sciences, policy, marketing, patient access, and medical affairs interact and work together towards a common goal. 

I believe that I now better understand the decision-making process in such a big organisation, which is clearly important in my role in order to influence direction and decision making within the company. 

One interesting aspect of joining industry was that I had to limit my involvement in social media. Although this may be perceived as losing independence, I still have a lot of choice in what I do in terms of what projects to pursue and what drugs to propose for development. 

Working with industry over the last 12 months has definitely given me ample opportunity for self-development, learning and training and offers me the chance to have an impact on the care and treatment of patients living with obesity likely far exceeding the impact I could have had working in academia or private practice.

Of course, I moved to industry at an advanced stage of my career allowing me to start at a rather senior position. However, many colleagues started their industry roles early in their careers and climbed the career ladder step by step. I don’t think there is a right or wrong way. 

One of the advantages of working in industry is that “changing tracks” is feasible. I have met many clinicians and scientists who ended up working in marketing, devices, regulatory affairs or machine learning and artificial intelligence for example. 

Based on my experience, I would certainly recommend to my clinical and academic colleagues to perhaps consider working with industry, both for the opportunities for self-development and having an impact on patient care. Especially, as we live in an era were moving between industry and academia and clinical work is feasible, the skills gained in one area are invaluable to the other. 

Whether working in academia, clinical practice or industry, all these efforts complement each other to ultimately reduce stigma and improve health care delivery to patients living with obesity by improving access to new and safe effective therapeutic options. 

Perhaps this post will inspire some of my clinicians and academic colleagues to consider the opportunities in obesity medicine within industry. I do not think there has never been a better time to be involved in obesity medicine for anyone who seeks to make a difference in the lives of people living with this chronic disease.

Abd A Tahrani MD, PhD

Copenhagen, DK

About the author: Abd Tahrani is currently the International Medical Vice President in Global Obesity Drug Development at Novo Nordisk. He is also an honorary consultant endocrinologist at the University Hospitals Birmingham NHS Trust (UHB) and an honorary senior Lecturer in metabolic endocrinology and obesity medicine at the University of Birmingham, UK. He has practiced obesity medicine since 2004 and was the lead for the weight management services at UHB and the lead for translational research at the Centre of Endocrinology, Diabetes and Metabolism at Birmingham Health Partners, UK. He has wide experience in obesity medicine, clinical research and health care delivery. He also worked extensively with patient organisations, policy makers, payers, national and international obesity societies, research funding bodies and educational institutes in the field of obesity.


Canadian Obesity Guidelines Double CMAJ’s Impact Factor

There can be little doubt in anyone’s minds that the 2020 release of the Canadian Clinical Practice Guidelines on Adult Obesity, a summary of which was published in CMAJ, represents both a landmark and a watershed in obesity medicine. 

Within 48 hours of its release, it received over 80 miillion media impressions around the world and the CMAJ summary was the #1 downloaded article on the CMAJ website in 2020. 

Just how large the impact of these guidelines were, is perhaps best reflected by the recent “thank you” note to the authors from Kirsten Patrick, Editor-in-Chief of the CMAJ, which notes:

I’m writing to thank you for contributing to CMAJ’s doubling its Impact Factor (IF) in this year’s report! CMAJ’s 2021 IF is 16.859. The highly-influential Guideline that you and your colleagues published in CMAJ in 2020 contributed to this big jump. Thanks for choosing CMAJ for your publication. I hope you’ll choose us again.”

In fact, according to Google Scholar, the guidelines have already been cited in over 150 articles and downloads of the PDF from the CMAJ website continues at a steady clip of over 2000 a month.  

This rather spectacular attention to these clinical practice guidelines (generally a rather mundane event that rarely catches the attention of lay media), is testament to the tremendous efforts and forward-thinking approach taken by the over 60 authors, who in 19 chapters layout our current thinking and evidence for addressing obesity as a chronic disease in clinical practice. 

While I congratulate CMAJ on this spectacular jump in its impact factor, I can only hope that this attention is reflected in the implementation of the over 80 recommendations by payers and health authorities as well as any health practitioners involved in obesity care.

As our knowledge continues to advance, I look forward to the continuing updates of these guidelines to ensure that these advances continue to improve the lives of the people living with obesity. 

Berlin, D


European Withdrawal of Amfepramone – End of an Era!

On Jun 10, 2020, the European Medicines Agency (EMA) recommended the withdrawal of amfepramone from the European market

This agent, belonging to the group of amphetamine-like stimulants, was authorised in Denmark, Germany, and Romania under the trade names Amfepramone Hormosan, Regenon, and Tenuate for weight reduction. 

Due to an increased risk of significant side effects including cardiovascular disease, pulmonary arterial hypertension, dependency and psychiatric disorders, as well as harmful effects if used during pregnancy, use of amfepramone was limited to no longer than three months. 

However, as the EMA review of amfepramone use revealed, 

“…amfepramone medicines continue to be used outside the current risk minimisation measures included in the product information.”

As the EMA could not see any further measures that would be sufficiently effective to minimise the risk of side effects, it concluded that the benefits of amfepramone medicines do not outweigh their risks and recommended that the medicines be removed from the market in the EU.

Notably, EMA also stated that other treatment options for obesity are available and that health professionals should inform patients about these options. 

Thus, it appears that at least in Europe, the era of amphetamine-like sympathomimetic medications for weight loss is finally coming to an end. 

No doubt, many health care professionals and patients, who may have relied on amfepramone in the past, will state that, despite possible risks, this medication at least was affordable to the many patient desperate for obesity treatment.

Indeed, the vast majority of patients seeking anti-obesity medications, who may have swallowed the rather low cost of amfepramone (pun intended), may well baulk at the cost of the newer class of GLP-1 analogues (liraglutide, semaglutide), despite being deemed safer and more effective. 

This issue will need to be addressed by fair pricing policies and the hope that the daily cost of liragutide will drop considerably once the more effective once-weekly semaglutide enters the market, thus providing an affordable alternative to patients, who have previously relied on amfepramone. 

Ultimately, I see no alternative than to include reimbursement for safe and effective anti-obesity medications in health plans, thus making these treatments available to more than just the upper 1% who can afford to pay out-of-pocket. 

Berlin, D


Guest Post: Reasons For Weight Regain

Today’s Guest Post comes from my friend and colleague David Macklin, MD, Toronto

Not long ago I received a message from a colleague looking for help with a patient who was regaining weight. As I thought about my response, it occurred to me that there should be a comprehensive list of why this happens, yet I could not remember coming across one. The following is a more detailed reproduction of the list I sent back to my colleague that day.  I’d like to thank Arya for suggesting that I share this list with his readership.  

An important note regarding this list:  Reason number one is the most important and most common reason for weight regain. The other reasons can make the primary reason more complicated.


The primary reason for weight regain is biology. The brain defends against weight loss because of an old biological play book.  If our ancestors lost weight, it was not to look good for a wedding or because of bathing suit season. Back then, weight loss was either because of illness or an interrupted food supply. Simply put, defending against weight loss was defending against death.  

In the last 30 years we have learned how the brain does this. The brain is expert at 1) recognizing fat loss, 2) defending against fat loss, and 3) promoting weight regain. The brain does this by:  

a) increasing appetite – the motivation for calorie intake

b) decreasing metabolic rate

Increased appetite seems to be more complicit than slower metabolism in weight regain. Increased appetite, in the form of an increased motivation to eat, leads to increased overall calorie intake, which in turn leads to weight regain.

A reminder, the remaining reasons for weight regain operate through the main mechanism, biology. 


The next common reason for weight regain relates to dieting.  Note that dieting is not an effective method of preventing weight regain. Instead, the three pillars to preventing weight regain are behavioural therapy, medication, and surgery. Simply put, the risk of weight gain is greater the more “diet-like” the weight-loss method. Specifically:

a) if the weight-loss effort involved a commitment to a reduced calorie intake that was unsustainable.

b) if the weight-loss effort involved a commitment to a level and type of effort that was unsustainable.

c) if the weight-loss effort did not accept and involve a conscious commitment to the value of fun, food, drink, friends, socialization, and travel.

The greatest predictor of thwarting weight regain is sustained adherence to the method used to lose weight. The above methods predict poor adherence.  They also predict that for someone losing too much weight, going to a weight lower than what is sustainable, weight loss will be overwhelmed by biology.

Thus, we have the definition of best weight. One’s best weight is arrived at by committing to the opposite of dieting. Best weight is discovered by committing to 1) a sustainable calorie level, 2) at a sustainable effort, 3) while accepting a conscious commitment to the value of fun, food, drink, friends, socialization, and travel. Best weight is the weight you softly land at when committing to a lifestyle that is, by definition, sustainable.


The next and rather poorly understood reason for weight regain is a sustained change in one’s overall environment. A common current example of this would be someone who was working in an office and is now working in their home, or the opposite: someone who was working at home and now is working at an office.  Another example is someone who, during weight loss, avoided high-risk settings for the purpose of weight loss and now inevitably is re-engaging in these setting. For example someone who avoided social setting or restaurants temporarily just for the purpose of weight loss. The cues in our physical and social environments trigger the biological response of appetite – wanting – the subconscious motivation to eat.  If the cues experienced during weight loss change, weight regain can follow.


Anti-obesity medications (AOMs) work by defending against an individual’s biology. AOMs defend against increased appetite and dampen the subconscious motivation for calorie intake (wanting).  If AOMs are discontinued or poorly complied with, the defence against weight regain is lost and the biology does the rest.  


A highly underestimated reason for weight regain is in an individual’s response to “weight loss setbacks.” Common weight loss setbacks include 1) the aftermath of off-track eating and/or drinking episodes, and 2) the moments after seeing a number on a scale not in one’s favour. Unless effective behavioural therapy has been provided, these setbacks may often be followed by negative self-critical thoughts and negative emotions including demotivation.  Yet it is precisely when one is at a lower weight that they are most subject to their biological drivers of weight regain and most likely to experience over-consuming and unfavourable scale results. Screening for and treating these unhelpful cognitive responses is an important part of understanding and addressing weight regain. To reiterate, this is probably the most underestimated non-biological complication of weight loss.


Weight gain can be a possible serious side effect of many commonly used medications. Some medications more commonly cause weight gain than others, and significant inter-individual differences exist. Weight regain may be caused by the addition of a weight-promoting medication and if possible, a substitution can be made for an alternative medication that is more weight neutral.


Finally, there is a finite list of internal states that may promote weight regain.  It is intuitive to most that stress, fatigue, lack of sleep, depressed mood, and lower levels of activity may promote weight regain. For many individuals, especially in a state of reduced body weight, each of these factors can increase wanting, the motivation to eat, and decrease self-regulation skills (restraint). If someone is regaining weight, it is imperative to screen for each of these modulators and to recognize how a change in any of these may be leading to higher calorie intake and weight regain.

For clinicians, and for those who struggle with weight, I hope this list is helpful.

David Macklin, MD

Toronto, CND

About the author: David A. Macklin, MD, is a lecturer at the University of Toronto and a University of Toronto trained family physician. He has practiced obesity medicine since 2004. He is the Medical Director of the Weight Management Program at the Toronto Medcan Clinic and co-author of the Canadian ACTION Study and the Psychology and Behavioural Treatment Chapter of the 2020 Canadian Clinical Practice Guidelines for the treatment of Obesity in adults.