Correlation does not equal causation, and it is both incredibly dangerous and irresponsible for anyone to use statistics in order to imply such a thing. I’ve seen this graphic in the #fitness tag several times now and I’m tired of ignoring it.
Concerning Depression: While greater odds for depression are found for the obese, that is not the largest indicator. In fact, there does not appear to be a simple or single association between these two descriptors. Meta-analytic studies suggest no statistically significant relationship. European Americans, women, the unmarried, the more educated, those with chronic physical disorder(s) and the offspring of depressed parents also experience highly increased odds of becoming depressed.
Concerning Dementia: It is unknown whether obesity is directly associated with specific patterns of brain atrophy. While dementia affects 6–10% of people 65 years or older, and industrialized countries have witnessed a rise in obesity in recent years, it is difficult to identify a definite link between these two sets of information. Looking strictly at numbers, without taking alternative influences into account, there is a parallel between BMI and dementia. Yet obesity is not the sole contributor: Both overweight and underweight patients are at increased risk of mental atrophy with age.
And let’s not ignore the phrasing of this statistic on the meme: "30% of people suffering from dementia are obese" eh? Considering that 35.7% of American adults are obese, and that dementia is typically associated with an aging population, this statistic is fairly meaningless. It just references the fact that both dementia and obesity are occurring in the same population.
Concerning Multiple Sclerosis in Children: Any links between obesity and multiple sclerosis in children have been hailed back to genetic predisposition, not lifestyle factors. The studies that attempt to directly link these two factors have been fairly inconclusive and faulty. It is still primarily believed that genetics play a primary role in determining who is at risk for developing MS, how the disease progresses, and how someone responds to therapy. Obesity is simply one small variant among many different family genes.
For reference, I have found one article that supports the “200% increased risk” claim made on this meme: Multiple Sclerosis Journal (2012). Considering that this was only published in September of last year, there has not been enough time for it to be fully reviewed. This article has the potential to hold weight, but it still needs to be backed up by alternative studies.
Concerning Heart Failure: 100% of all
human beings things with a heart are going to experience heart failure. That’s sort of what happens when you die: Your heart stops and fails to continue pumping blood. This statistic is therefore nothing more than a scare tactic. It provides us with absolutely no context or further explanation about how obesity may influence our heart’s functioning.
If we’re going to take a serious look at the correlation between obesity and heart failure, then it’s necessary to use more precise and meaningful language: In patients with chronic heart failure (CHF), studies have reported reduced mortality rates in patients with increased BMI.
Let’s repeat that: Obesity is associated with lower all-cause and cardiovascular mortality rates in patients with CHF and are not associated with increased mortality in most studies. According to a 2008 meta-analysis of published literature, there actually isn’t a proven association in any study at all.
This is often described as the “Obesity Paradox.” Obese patients who experience heart failure are more likely to survive the trauma than those at a “healthy weight.” In contrast, underweight patients are more likely to pass away when experiencing the same cardiac symptoms.
Concerning Asthma: Obesity is significantly associated with an increased risk of nonatopic asthma only, not atopic asthma. We need to create a clear distinction between these two types when discussing how weight may influence the development of “asthma” as a whole: Yes, the association of nonatopic asthma severity with obesity suggests that obesity may be a potentially modifiable risk factor for asthma or asthma‐like symptoms. Yet there is next to no association between obesity and the development of atopic asthma.
Obesity and asthma may actually share a common etiology, such as common genetics and in utero conditions. In all cases, obesity may not necessarily cause asthma to develop. Instead, they both develop from a common predisposition.
In the case of a respiratory disease, it is also necessary to ask: How many people are obese because of asthma? Given that asthma has the potential to drastically reduce the amount of cardiovascular activity that a person can safely engage in, it is not out of line to recognize that the illness has the ability to limit one’s activity, thus causing them to lead an increasingly sedentary lifestyle, thus leading to a heavier weight than a patient would otherwise experience. The relationship between these two health factors does not always have a clear cause and effect: Obesity and asthma are very inter-related.
Concerning Diabetes: It is irresponsible to discuss “diabetes” as though it is one inclusive disease: It identifies a group of metabolic diseases. Instead, the conversation should be framed in terms of Type I, Type II and gestational diabetes (as well as numerous other forms that exist among smaller groups of patients).
Type I diabetes is an autoimmune disease. Researchers currently do not know exactly what causes the body’s immune system to attack the beta cells, but they believe that autoimmune, genetic, and environmental factors(such as viruses) are involved. In contrast, Type II diabetes is highly often associated with older age, obesity, family history of diabetes, previous history of gestational diabetes, physical inactivity and certain ethnicities. It is type II diabetes that has clearly been shown to have a link with obesity: About 80% of people with type 2 diabetes are overweight or obese.
These two types cannot and should not be discussed as though they are the same: Lumping them together is only going to create unreliable conclusions and misinformation. If we’re going to look at Diabetes as a whole, then this graphic’s statistic of 50% is inaccurate. Instead, that number will fall to around 36%. (Remember that we’re talking about obesity here, not just being overweight.)
But especially in this case, it’s necessary to remember that other factors influence the way in which diabetes is treated in many patients. Doctors have a tendency to provide different levels of treatment to obese vs “normal” weight patients. These different treatments often have no basis in medical reasoning, but rather in social bias. This plays into the Obesity Paradox as well - Obese diabetics may receive more rigorous treatment since they are deemed to be “extreme” and dangerous cases, while more “normal” weighted patients may not even be tested for diabetes because it is socially believed that they are less likely to develop it. Doctors will explore other options before considering diabetes-related treatments. Therefore, people with lower weights may be undiagnosed diabetics and therefore skew statistics.
Concerning High Blood Pressure: You’d be hard pressed to find a study that directly links obesity as the cause of high blood pressure, making this statistic rather misleading. Instead, high blood pressure and higher weights have the (broad) tendency to develop from the same basic lifestyle factors: diet and overall activity will have a small influence on both, as will environment and genetics. An obese patient who eats a balanced diet and regularly engages in exercise is far more likely to have normal blood pressure levels than a “normal” weighted person who has a high-sodium diet and sedentary lifestyle.
This is a case where multiple risk factors must combine in order to create a patient who experiences both obesity and high blood pressure at the same time. Losing weight will not inherently aid the patient in obtaining a lower and healthier blood pressure: It is necessary to directly target their environment first, not their body. Losing weight will provide no additional benefit (in regard to blood pressure) unless the other risk factors are eliminated as well.
Here, obesity is being used as an easy scapegoat, rather than being recognized as an effect.
Concerning Cancer: Correlation does not equal causation: While certain types of cancer may be more commonly found in obese patients, it is highly irresponsible to say that obesity caused that cancer to develop. This is an important distinction to make.
Primarily because few obese people are successful in long-term weight reduction, there is very little direct evidence surrounding the impact that weight reduction may have on cancer risk. We need more information from long-term studies in order support any clear link between one’s weight and their risk of cancer. Until that time, it is largely necessary to view obesity as a “predictive factor” of cancer, not as a direct cause.
In conclusion: I’ve got no patience for your fatphobia and scare tactics, I’m too busy dealing with the facts.
IOW, genetic and epigenetic causes. And a bit more on some negative effects of keeping bashing people with the fat hatred and blaming around this:
That author put it a lot better than I could have, which is why all the quoting.