The ROOTS of Obesity

The human body has in-built mechanisms to protect itself from starvation – this can make it hard to maintain weight loss.

The body is designed with an important defense system to prevent starvation. But when we gain excess body fat, this system defends our higher fat level.

Body fat produces an important hormone, leptin, which signals the brain how much fat is stored. When fat levels fall and leptin falls, the brain interprets this as starvation and switches metabolism to energy saving, and changes appetite to increased hunger and decreased fullness. This works well to keep our body weight from falling. 

But this system is not so good at adapting when we gain extra fat. The body’s response to high leptin levels doesn’t always work… the brain seems to have “leptin resistance.” When we try to lose weight, fat and leptin levels fall and the body increases hunger, decreases fullness and conserves energy. This resists weight loss and promotes weight regain. When we try to lose weight and keep it off, we are in a ‘tug of war’ with our body’s regulatory system.

Proven strategies to fight weight regain are to adopt behavior that help overcome the biology. These include monitoring weight, eating regular and healthy meals and engaging in daily physical activity.

Processed food, now seen across the globe, is contributing to the rapid rise in obesity.

Over the past few decades, the food environment has changed dramatically. Most notably, there has been a significant increase in processed foods which are widely available, calorie-dense, nutrient-poor, affordable and heavily promoted. The desirable taste and textures of processed foods, combined with the appealing packaging and extensive marketing, are associated with brain appetitive control systems that increase appetite, food motivation, and food reward value and can result in increased food intake. Typically, processed foods are also much cheaper than more nutritionally beneficial and unprocessed foods which further displaces healthy food consumption, especially in more disadvantaged populations.

The obesity epidemic has emerged in the last 40 years, and mirrors these changes in the food environment. Once associated with Western diets, the increase in processed foods is now seen in many low- and middle-income countries and is undermining local diets and contributing to the rapid rise in obesity.

Our genes account for somewhere between 40-70% of the likelihood of having obesity.

We inherit our genes from our parents, and it has been estimated that 40-70% of our chance of having obesity is due to our genes. There have now been hundreds of genes identified which can contribute to the risk of obesity. Most of these genes by themselves have a small effect, but when combined can significantly increase the risk for obesity. While our genes play a fundamental role in influencing our risk for obesity, how our genes interact with our environment can impact this risk, in both good and bad ways. While our genes influence our risk for obesity; the impact of their contribution can be modified by environmental factors such as our lifestyle habits.

Without access to trained providers, most people who suffer from Obesity won’t reach and maintain a healthy long-term weight goal.

In almost all high income countries, people who suffer from the chronic disease of obesity must be provided with affordable and reimbursable access to specialised healthcare providers who can treat the disease with individualized treatment approaches of diet, anti-obesity medication, behavior and exercise options that are unique to the individual; in some cases that may also include surgical intervention.

Care provided by a properly trained clinician who either specializes in Obesity Medicine or has extensive training in the use of anti-obesity medication and treatment plan options, is still not readily available in most areas. Obesity is a complex, chronic disease with many contributing factors that challenge primary care and obesity medicine specialists alike, but without access to properly trained specialty providers, most people who suffer from Obesity will not be able to reach and maintain a healthy long-term weight goal.

Access to healthcare in itself can be challenging based on geographic clinician shortages, transportation barriers, insurance coverage and the lack of trained obesity medicine specialists, especially since most Medical School programs do not offer specialized Obesity care curriculum yet.

The general lack of awareness that obesity is indeed a disease within the medical community at large, and the public’s belief that obesity is the result of a lifestyle choice and not a disease, creates an additional barrier to treatment. This is especially the case in low- and middle-income countries, where health systems are especially poorly equipped to manage the challenge. A recent study of obesity in health systems in more than 60 countries found that most lack adequate services to tackle obesity. The main reasons mentioned for lack of treatment were lack of care pathways from family physician to secondary services; insufficient secondary, multi-disciplinary services and trained professionals; high costs to patients; the prevailing obesogenic environment; and stigma experienced by patients within the health care services. In many countries, merely entering the health system – and remaining in it – are cited as being among the biggest hurdles faced by patients living with obesity. Respondents in 47% of the countries stated that there were difficulties obtaining referrals for obesity treatment, while a lack of treatment options and clear pathways to treatment were mentioned as problems, especially in lower-income countries.

Respondents in 37 countries (54%) stated that the main funding for treatment would be provided by the patient (‘out-of-pocket’ payments) while in only four countries (6%) re-spondents stated that government funding or insurance funding was the main means for paying for treatment. This is exacerbated by the lack of training for health care profes-sionals in obesity diagnosis, management and treatment. Specific skills that are currently missing in most healthcare systems are: proper obesity diagnosis, recognising endocrine or orthopaedic problems, providing bariatric surgical skills, providing expert advice in pregnancy, providing appropriate advice on nutrition and physical activity, and providing psychological and behavioural support. Furthermore, these skills should be part of the necessary training of a multidisciplinary team to support treatment and follow-up, which is missing in an overwhelming majority of healthcare systems.

When it comes to the complex treatment of obesity, we must focus on disease awareness, specialty clinician availability, early diagnosis and access to specialty care for all life stages from pediatric patients to senior adults. Long term access to specialized obesity medicine care is key to the success in treating obesity.

Prenatal life, early adulthood, pregnancy, illnesses and medications can all influence weight gain.

Events that occur across the course of one’s life can be drivers of weight gain. Infancy and prenatal life are critical periods where nutritional factors can predispose to obesity in adulthood.

Early adulthood: In high-income countries like the United States, from age 20-40, average weight gain is 1-2 pounds (1/2 to 1 kg) per year. Some people gain even more than average, especially when exposed to weight gain drivers like sedentary lifestyle, emotional or financial stress and sleep disturbances or shift work.

Pregnancy: With the birth of every child, the mother will retain on average 2 pounds (1 kilogram). Some women retain more. That adds up with multiple births. Menopause in women: While studies don’t confirm excess weight gain with menopause itself, there is a shift in body fat distribution to a less favourable, “apple shape” pattern, which is associated with more risk for diabetes and heart disease.

Some Illnesses (such as depression) and some medications (such as steroids for asthma and some antidepressants) can produce weight gain. If you are struggling with your weight, bring a list of your medications to your health care provider. Changing medications associated with weight gain may help with weight loss.

There is a complex relationship between food systems and health, with marketing of foodstuffs having a known link to obesity.

Obesogenic environments (comprised of many different elements, including food availability, affordability, public transportation, and marketing, among others) have been proven to promote obesity in individuals and populations.

Together, these components transform food environments and food systems. Unfortunately, in low-middle income countries (LMICs), unhealthy food environments are the norm. Over the past ten years, the role of marketing in food environments has been studied at length.

In Latin America, for example, studies have shown that marketing strategies are used to appeal to children through the use of cartoon characters, promotions, and product placement. There is significant evidence that marketing influences consumption choices and that it is associated with a poor-quality diet. This includes the consumption of ultra-processed foods which we now know cause obesity. Furthermore, interventions to restrict the reach of marketing have been effective in reducing children’s exposure despite food industry interference, which continues to be a significant barrier to implementing and treating obesity.

Symptoms of some mental health disorders, and their associated medications, can lead to weight gain.

Obesity and mental health are deeply entwined. Some mental health disorders can have symptoms such as lethargy, decreased sleep, excessive sleep, and increased appetite, which can lead to weight gain. Some treatments for mental health disorders (e.g. antidepressant and antipsychotic medication) have been associated with moderate to significant weight gain. Research has observed that individuals who have genes that are associated with having a high BMI are at a greater risk of having depression. Experiencing weight stigma can also increase risk for mental health disorders (e.g. anxiety and depression).

Lack of sleep disturbs hormones which can affect your weight – as can high levels of stress.

Lack of sleep (both duration and quality) is linked to diseases such as cardiovascular disease, depression, and obesity. Specifically, when it comes to obesity, a lack of sleep can disrupt hormones such as increased cortisol (a stress hormone linked to weight gain) and increased ghrelin (a hormone that stimulates appetite and cravings), and decreased leptin (a hormone that tells your brain when you are full). High levels of stress hormones can make you more likely to crave sugary, fatty and salty foods. Managing sleep problems can help you have more energy, eat less and generally feel better. Reducing day-to-day stress levels where you can or improving ways you deal with stress can lead to positive effects on these factors, as well as on your overall weight-management plan.

Weight discrimination and stigma can have significant consequences on somebody with obesity.

Weight bias are negative attitudes and beliefs we have about people living in larger bodies. Obesity stigma are deeply ingrained social stereotypes associated with obesity and people affected by obesity. Weight discrimination is the unjust treatment of individuals because of their weight. Weight bias, stigma and discrimination can have significant physical, psychological and psychosocial consequences. Obesity stigma can increase risk for obesity (e.g. increased stress hormones that promote weight gain, behaviours that promote weight gain such as avoiding health promoting environments for fear of being shame and blamed for one’s weight). Obesity stigma can also have social and economic consequences for individuals living with obesity, such as fewer opportunities for education and employment. 

Internalized weight bias, or self-directed bias, is the extent to which individuals living with obesity endorse negative weight-biased beliefs about themselves and can impact health and obesity management outcomes.