What do we actually know about obesity?
Authors: Dr. Ashok Bhandari & Mark Heisig
Recently an article in Huffington Post titled, “Everything you know about obesity is wrong,” was published and widely shared on social media platforms by both medical professionals and the general public alike. An emotionally charged article with a mess of research cited, we felt it necessary to sift through the clutter as it relates to physical health. Is everything we know about obesity wrong? Is the medical management of obesity a medical error? Is there true physical and physiological health at every size?
Disclaimer: We, the authors, feel it necessary to address this very early on – This is not an article surrounding, evaluating, or asserting opinions on shame or discrimination of overweight/obese people. The discrimination, shame, and lack of compassion directed towards individuals with overweight/obese body habitus, both socially and medically, is unacceptable. That is without question. This article aims to evaluate and discuss what we, as a scientific community, know about the physical nature and outcomes related to carrying excess amounts of adipose. We also present our solutions at the end of this article. This article is not without cause.
Let’s set the stage
Before we even get into reviewing the specifics of this article, we first need to establish a foundation of common ground from which we can all look at health and disease. One method or paradigm often used in medicine as a framework is crudely represented as:
Risk Factors → Disease State/Health Condition → Outcomes/Negative Sequelae
When applied to well-known associations and pathological processes, this makes logical sense. For example:
- Smoking/Family history of lung cancer → increased damage of lungs/lung cancer → Early death due to lung cancer
- Adequate servings of fruits/vegetables everyday → higher likelihood of healthy cardiometabolic biomarkers (blood lipid levels, glucose regulation, etc.) → decreased risk of early death due to cardiometabolic disease (heart disease, diabetes, hypertension, etc.)
Of course, neither of the above scenarios are absolutes; they are general associations of increased/decreased risks that we face in life. No two individuals respond identically or share equal risk/benefit ratios, hence the bell curve distribution of health outcomes. So, that leaves us with looking at the most likely scenarios. In medicine, we assess risk factors and predispositions for disease, mitigate these using the “most likely to work” interventions, in hopes of decreasing morbidity and mortality, and increasing quality of life. So we arrive at some basic questions:
Are these risk factors clinically relevant for this person?
- Will this therapy or recommendation lead to greater health outcomes?
- Will this therapy or recommendation improve quality of life?
- Can I lower the risk of other diseases (comorbidities) or adverse outcomes (i.e., death)?
Now, if we take this very same method of thinking, and use these very same questions to address the topic of obesity, where does that land us? Well, let’s see…
Obesity, in and of itself, is kind of tricky. Is obesity a risk factor or predisposition for disease, a disease state, or is it an outcome of disease states/conditions? Does it matter? First, the most prevalent method of defining obesity has been flawed, at best. BMI, body mass index, has been used in the medical world for at least the last century, to help define “obesity.” BMI, however, is not a good indicator of this, and this is one point that the HuffPost article author did a good job of pointing out. BMI was originally introduced into medicine as a concept used by an insurance company to define ‘healthy’ standards of weight-to-height ratios, which in turn would be used for determining insurance premiums. However, stopping there by saying “therefore obesity doesn’t matter,” is short-sighted. The CDC itself acknowledges it is a flawed measure only to be used for screening populations, and not as a diagnostic tool. The better classification of “obesity” comes out of using the definition: “overweight and obesity are defined as abnormal or excessive fat accumulation that presents a risk to health.” Key point: the definition hinges upon excessive FAT (adipose, or triacylglycerol) accumulation. Not WEIGHT.
“I have firsthand experience with BMI being a wildly inaccurate reflection of my body fat, health, and fitness status. At the age of 17, in preparation for college hockey, my 5’8” frame had 185lbs on it at one point. Do the math, and my BMI was overweight at 28.1, and only 1.9 points away from categorizing me as obese. Over one year later, playing for NAU, I weighed 165lbs making my BMI 25.1. That still classified me as overweight. Was I unhealthy and truly over-fat in any of these periods? Nope. Was BMI useful in my playing years? Nope.”
– Mark Heisig
Reference ranges put forth by the American Council on Exercise (ACE), shown below in the table, presents varying normative values for body fat percentage based upon physical fitness. The American College of Sports Medicine (ACSM) has recommendations based upon sex, age, and percentile with a range from “Very Poor” to “Very Lean.” Very poor for women begins at 30.5% body fat, while very poor for men begins at 24.9% body fat; very similar to the reference ranges put forth by ACE.
|Description (Body Fat Category)||Women (% Body Fat)||Men (% Body Fat)|
To summarize, based on the data above regarding body fat percentage, we can conclude that women over approximately 30%, and men over 25% body fat percentage, can be categorized as carrying excess amounts of adipose tissue. Simply put, this is where the truest definition of “obese” fits; when fat mass begins to account for a higher proportion of total body weight, the body faces increased metabolic, endocrine, and mechanical stresses. This stress is independent of total body weight. So, for those of you who are now considering the idea of “skinny fat” – those individuals that are low body weight but higher percent body fat – this risk still applies. Lower total body weight may impose less mechanical stress on the body; however, an increase in metabolically and hormonally active adipose tissue still increases the risk for poor metabolic and endocrine outcomes. The scenario of appropriate body fat with significantly increased total body weight – essentially the flip side of “skinny fat” – also poses health risks. Let’s consider a strong, heavy, professional athlete like an NFL linebacker. Despite the healthy proportion of fat mass and fat-free mass, the high overall total body mass presents significant mechanical stress to the heart. This stress comes in the form of increased total peripheral resistance, increased blood vessel length and number, and total mass to support. The research here again supports the idea of moderate total body weight, and appropriate body composition proportions – those with excessive mass tend to die sooner.
“A lean body isn’t always a fit or healthy body, or belong to a person with good habits. A body with more fat isn’t always an unfit or unhealthy body… A light body doesn’t mean a fit or healthy body. A big or heavy body isn’t always an unfit or unhealthy body.”
– Berardi, J., & Andrews, R.
Perfectly complicated, with just enough evidence to support moderation.
Before we move on, let’s recap real quick.
We are acknowledging that:
- Obesity is a complex issue with numerous physical and psychosocial factors all contributing to its manifestations and management.
- The use of BMI for defining obesity is inaccurate. The CDC even acknowledges that BMI is likely only useful for population data vs. individual clinical management.
- Obesity is better defined by the percentage of fat mass as a proportion of total body weight. The cutoff for men is 25% body fat and 30% body fat for women. This percentage of fat is more useful as it captures individuals with apparently healthy body weight or appearance, but unhealthy adipose levels (i.e., “skinny fat”).
- A further complication is that total body mass, healthy or not, still does appear to place a mechanical strain on the heart.
What We’ve Learned About Metabolically Healthy Obese (MHO)?
The idea of metabolically healthy obese comes from looking at individuals that carry higher percentages of body fat, possibly appear overweight or obese, but have otherwise “healthy” markers of metabolic health. These markers include lipid levels (cholesterol), blood pressure, and blood glucose levels. Recent years of research have tried to characterize this unique subgroup of obese individuals, and their relative risk profiles, as compared to non-healthy obese, and non-obese counterparts. Blüher and Schwarz (2014) further attempted to quantify the details of metabolic profiles in MHO individuals when compared with non-MHO (metabolically unhealthy obese) individuals. A brief look at their findings is summarized in the image below.
As you can see above, we find that MHO individuals tend to have lower markers of inflammation, preserved blood sugar regulation, and lower amounts of visceral (organ) adiposity when compared to metabolically unhealthy obese individuals, or non-MHO individuals. The claim that comes next, which appears logical, is that MHO individuals must be exempt from the clinical consequences seen in non-MHO individuals. The commonly cited example of this is when researchers correlated higher BMI levels with being cardioprotective (i.e., possibly beneficial for the heart). However, reevaluation of this research demonstrates that higher BMI is not as cardioprotective as previously reported. “In this study, obesity was associated with shorter longevity and significantly increased risk of cardiovascular morbidity and mortality compared with normal BMI. Despite similar longevity compared with normal BMI, overweight was associated with significantly increased risk of developing CVD at an earlier age, resulting in a greater proportion of life lived with CVD morbidity.”[10,11]
What we are finding in the literature is that, rather than being “black or white,” protective or not, there is more of a grayscale in risk as an accumulation of unhealthy levels of adipose occurs, independent of “metabolic health.” What this means is that MHO is not a protective phenotype. MHO is a phenotype that carries more risk than a healthy weight phenotype, but less risk than a non-MHO phenotype. Multiple studies, shown below, have found MHO individuals still have an increased risk for all-cause mortality, cardiovascular events, type II diabetes, impaired microvascular function, and metabolic dysregulation.
The MHO phenotype may not carry AS MUCH risk as the non-MHO phenotype. However, this does not imply that the MHO phenotype is healthy. As shown below, the MHO phenotype carries more risk for cardiometabolic disease and adverse clinical outcomes than a healthy weight phenotype. There is even evidence to support that the MHO phenotype is likely a transient phenotype with potential for progression into either a metabolically healthy normal-weight (MHNW) phenotype or a metabolically unhealthy obese (MUH) phenotype.
Evidence for the “MHO risk scale”:
- “This study yields 3 key findings. First, compared with metabolically healthy normal-weight persons, metabolically healthy obese individuals are at increased risk for all-cause mortality and CV events over the long term (10 years). Second, all phenotypes with unhealthy metabolic status present increased risk, regardless of normal weight, overweight, or obesity. Third, blood pressure, waist circumference, and insulin resistance increased, and HDL cholesterol decreased, across the BMI categories in both metabolically healthy and unhealthy subgroups.”
- “Metabolically healthy obese adults show a substantially increased risk of incident type 2 diabetes compared with metabolically healthy normal-weight adults. Existing prospective evidence does not indicate that healthy obesity is a harmless condition.”
- “Our results suggest that obese individuals without metabolic abnormalities have more impaired microvascular function when compared to their normal-weight counterparts. Although we emphasize that metabolic disturbances strengthen the association of excess weight to impaired vascular function, our data indicate that increased weight is detrimental to vascular health irrespective of metabolic status, challenging the concept of a healthy pattern of obesity.”
- “MHO is an important, emerging phenotype with risks somewhere intermediate between healthy, normal weight and unhealthy, obese individuals.”
So where does this leave us?
Now that we know that MHO can exist, but it is NOT a healthy, benign alternative to a healthy body-fat percentage, how do we successfully address obesity?
Problems With The Conventional Approach
Everyone in medicine wants to help. We thoroughly believe that no medical professional is purposely providing inadequate care for the overweight and obese population.
However, most are just not adequately prepared for this task. Conventional training for medical doctors (MDs) offers little to no nutritional education beyond the basics of the food pyramid recommendations or some general guidelines of diets used for specific conditions (e.g., DASH or Mediterranean Diets for hypertension). Even then these recommendations are minimally enforced, and the next step in the algorithmic clinical thinking process (e.g., reactive pharmaceutical symptom management) is quickly performed. Again, this is not because they do not care – it’s because they’ve reached the bottom of their respective toolbox and the limits of their clinical training. Couple that with minimal training for mental health approaches or behavior change techniques, such as motivational interviewing (MI) in the management of obesity or cardiometabolic disease, and you’ve got a recipe for the current poor management and approach to obesity that we see today.
In addition, most physicians know less about exercise than your local personal trainer. If your doctor has recommended 150 minutes of weekly exercise, then they have done their due diligence per most major medical association guidelines and standard of care recommendations. However, this passing recommendation is rarely enough for making serious and lasting metabolic changes.
Confounding Problems Outside of Healthcare
The food industry has made literally trillions from pushing processed, nutrient-deficient, calorie-dense foods. They’re cheap, easy, and taste phenomenal. The food industry has spent billions researching the science of human brains and our rewards centers (like dopamine function) and specifically created foods to keep us addicted. We stay addicted, and from the overindulgence in high caloric, low-nutrient, and for lack of a better term, “dirty foods,” we as a society have gained a tremendous amount of weight, most of which is fat mass. We haven’t provided links to research on this topic, but the original author of the HuffPost article also discusses this obstacle to health.[1,16]
Our Proposed Solutions
The first step is to acknowledge that there is a legitimate spectrum of risk that exists with the accumulation of body fat. It is safer for our patients, and us as individuals, to maintain healthy levels of body fat than to accumulate too much adipose or to lose too much adipose. Individualized treatment plans, guided and supported by a well-equipped medical professional (e.g., Naturopathic physician (ND) or a functional medicine doctor), are the most effective methods of achieving long-lasting results. An adequately-trained medical professional can also address further co-morbidities that prevent successful fat loss and body composition changes. These include thyroid disease, food sensitivities/allergies, HPA axis dysfunction, other hormonal imbalances, environmental toxicities, and many, many more confounding conditions. Naturopathic doctors receive over 150 hours in clinical nutrition education and specific counseling training in addressing mental/emotional health as well.
Therefore, a medical professional who can address the metabolic, hormonal, environmental, and psycho-social aspects of losing fat mass, can most effectively help a patient overcome the hunger, cravings, and low energy that can accompany the process of diet and lifestyle modifications. Finally, coupling this integrative assessment and management approach with appropriate exercise recommendations that are, again, individualized and goal-oriented, may significantly affect an individual’s ability to sustain a fat loss treatment plan. The evidence is unambiguous on exercise and physical activity: cardiorespiratory fitness is likely what determines the prognosis of MHO individuals staying healthy, becoming MHNW, or becoming MUH (whether overweight or healthy weight).
For an exhaustive review of the evidence-based health benefits of exercise, please refer to the American College of Sports Medicine (ACSM).
The ACSM is where the standard of care exercise recommendations are derived. The general, population-based recommendations are great foundation guidelines when appropriately applied and executed. Beyond these simple steps, individualized exercise programs are what indeed produce the most significant health outcomes, helping people achieve their specific goals while minimizing resistance and obstacles to change.
Does Medical Attention and Treatment Work?
This is actually a serious point of contention we had with the original HuffPost article.
The author had stated repeatedly that medical science is neglecting evidence surrounding weight management, that medical interventions which focused on weight loss are ineffective, and that weight-loss is an inappropriate medical focus. As we have demonstrated above, weight status determined through BMI is an inaccurate reflection of health status. However, unhealthy distributions of body fat, which are typically accompanied by larger body habitus and more substantial weight, do pose health risks. Moreover, weight loss reduces these health risks.
The article from HuffPost cites the U.S. Preventive Services Task Force (USPSTF) saying, “In 2017, the U.S. Preventive Services Task Force, the expert panel that decides which treatments should be offered for free under Obamacare, found that the decisive factor in obesity care was not the diet patients went on, but how much attention and support they received while they were on it. Participants who got more than 12 sessions with a dietician saw significant reductions in their rates of prediabetes and cardiovascular risk. Those who got less personalized care showed almost no improvement at all.”
The author claimed that attention and support was the critical factor in achieving health outcomes – which we agree that attention and support are critical, hence our recommendations for an ND or functional medicine practitioner. However, if you look at the USPSTF reference that was used to make the claims, you find that the US Preventive Task Force considers obesity (BMI >30) a medically important health burden. The studies looking at “attention and support” were in fact studies looking at behavioral interventions aimed at achieving a weight loss of 5% or greater. From the USPSTF themselves, “The USPSTF found adequate evidence that behavior-based weight loss interventions in adults with obesity can lead to clinically significant improvements in weight status and reduced incidence of type 2 diabetes among adults with obesity and elevated plasma glucose levels. The USPSTF found adequate evidence that behavior-based weight loss maintenance interventions are associated with less weight gain after the cessation of interventions, compared with control groups. The magnitude of these benefits is moderate.”
To sum up, our biggest qualm with the author using the USPSTF reference to say that weight loss is not a useful goal was that the USPSTF specifically studied weight loss as the useful goal. Know your science before you go viral with it, and quote your references accurately.
Obesity is a complicated subject.
Weight, BMI, and obesity are all very charged areas of debate. That said, much of medicine is emotionally charged. Disease is physically, mentally, and emotionally trying. Every condition and disease state carries with it some sort of burden, personal or otherwise, and we address risk factors accordingly. However, the fact that obesity and weight loss are difficult topics of discussion, and can often be just as challenging to manage, does not mean we should disregard the potential effects on overall health. Especially when this is a decision made from a perspective of potentially “sparing one’s feelings.” We must be even more diligent in putting our energy towards finding effective strategies to work with people, at a population level, and at the individual level, to remove the obstacles to cure and support our natural ability to be metabolically, mentally, emotionally, hormonally, and physically fit and healthy.
Everything we know about obesity is that it is tricky – and most certainly carries an increased risk of all-cause mortality, cardiovascular disease, type II diabetes, among other things. The degree of risk may correlate with other metabolic measures, but the literature is quite clear that excessive adiposity is not healthy.
Let’s move past debating whether this is an issue of concern or not, and move towards finding compassion and acceptance for those who need the support in making these difficult changes. With so much already working against our health-promoting actions, the last thing we need to do is debate whether any of this is even worth it, or to point fingers to push blame. Acceptance and compassion are necessary contributions from both medicine and patients. Consistency and teamwork are no different.
When medicine and patients can work together to create individualized and integrative treatment strategies, great beneficial changes can be achieved in lowering disease risk, improving health, and improving quality of life. This is how the impossible becomes attainable.
(This article can also be found on AZVHealth.com)
- Hobbes, M. (2018). Everything You Know About Obesity Is Wrong. [online] The Huffington Post. Available at: https://highline.huffingtonpost.com/articles/en/everything-you-know-about-obesity-is-wrong/ [Accessed 19 Sep. 2018].
- Centers for Disease Control and Prevention. (2013). Body mass index: considerations for practitioners. Centers for Disease Control and Prevention: Atlanta, GA, USA.
- Obesity. (2014, September 05). Retrieved from http://www.who.int/topics/obesity/en/
- Li, C., Ford, E. S., Zhao, G., Balluz, L. S., & Giles, W. H. (2009). Estimates of body composition with dual-energy X-ray absorptiometry in adults–. The American journal of clinical nutrition, 90(6), 1457-1465.
- American College of Sports Medicine. (2009). Health-related physical fitness testing and interpretation. ACSM ‘Guidelines for Exercise Testing and Prescription, 60-73.
- Pokharel, Y., Basra, S., Lincoln, A. E., Tucker, A. M., Nambi, V., Nasir, K., … & Ballantyne, C. M. (2014). Association of body mass index and waist circumference with subclinical atherosclerosis in retired NFL players. Southern medical journal, 107(10), 633-639.
- Berardi, J., & Andrews, R. (2010). The Essentials of Sport and Exercise Nutrition. Precision Nutrition 2013.
- Kramer, C. K., Zinman, B., & Retnakaran, R. (2013). Are metabolically healthy overweight and obesity benign conditions?: A systematic review and meta-analysis. Annals of internal medicine, 159(11), 758-769.
- Blüher, S., & Schwarz, P. (2014). Metabolically healthy obesity from childhood to adulthood—does weight status alone matter?. Metabolism, 63(9), 1084-1092.
- Khan, S. S., Ning, H., Wilkins, J. T., Allen, N., Carnethon, M., Berry, J. D., … & Lloyd-Jones, D. M. (2018). Association of body mass index with lifetime risk of cardiovascular disease and compression of morbidity. JAMA cardiology, 3(4), 280-287.
- Hughes, S. (2018, March 7). Obesity Paradox in Heart Disease Challenged by New Analysis. Retrieved from https://www.medscape.com/viewarticle/893538
- Bell, J. A., Kivimaki, M., & Hamer, M. (2014). Metabolically healthy obesity and risk of incident type 2 diabetes: a meta‐analysis of prospective cohort studies. Obesity reviews, 15(6), 504-515.
- Brant, L. C., Wang, N., Ojeda, F. M., LaValley, M., Barreto, S. M., Benjamin, E. J., … & Blankenberg, S. (2017). Relations of metabolically healthy and unhealthy obesity to digital vascular function in three community‐based cohorts: a meta‐analysis. Journal of the American Heart Association, 6(3), e004199.
- Roberson, L. L., Aneni, E. C., Maziak, W., Agatston, A., Feldman, T., Rouseff, M., … & Al-Mallah, M. H. (2014). Beyond BMI: The “Metabolically healthy obese” phenotype & its association with clinical/subclinical cardiovascular disease and all-cause mortality–a systematic review. BMC public health, 14(1), 14.
- Busko, M. (2017, October 13). Nutrition Training for Young Doctors Lacks Bite. Retrieved from https://www.medscape.com/viewarticle/886722
- Meule, A. (2015). Focus: Addiction: Back by popular demand: A narrative review on the history of food addiction research. The Yale journal of biology and medicine, 88(3), 295.
- Comparing the ND & MD Curricula. (n.d.). Retrieved November 1, 2018, from https://aanmc.org/resources/comparing-nd-md-curricula/
- [Ortega, F. B., Cadenas-Sanchez, C., Migueles, J. H., Labayen, I., Ruiz, J. R., Sui, X., … & Lavie, C. J. (2018). Role of physical activity and fitness in the characterization and prognosis of the metabolically healthy obesity phenotype: a systematic review and meta-analysis. Progress in cardiovascular diseases.].
- Final Recommendation Statement. (n.d.). Retrieved November 1, 2018, from https://www.uspreventiveservicestaskforce.org/Page/Document/RecommendationStatementFinal/obesity-in-adults-interventions1