Apparently, most people in the business see stress eating and comfort eating as the same phenomenon under different names, and both are included under the heading of emotional eating. When researchers look back over previous contributions to the knowledge base, and design meta-studies, inconsistency is a problem.
Different academics start out with different subject populations and use different scales to measure things by. They are working with intangibles like depressive symptoms and perceived psychological stress.
While interviewing subjects about adverse life events may be quite useful, a survey format is more commonly used, which is vulnerable to reporting bias and inaccurate memory. The current stress level in people’s lives and their current levels of depressive symptoms can color the way they look at adverse events in retrospect.
Is their stress acute or chronic? Being in a frightening car accident is a different kind of stress than caring for a disabled child. To top it all off, most of this research has concerned young women, and not much is known about men.
A. Janet Tomiyama and two colleagues asked these questions and others:
What would constitute evidence of the effectiveness of comfort eating? Is dampened physiological stress reactivity sufficient, or must it also coincide with decreases in negative emotion? What if negative emotions are unaffected, but positive emotions increase?
They note that progress in this research area would be greatly facilitated if all researchers used consistent standards and aimed for the utmost precision. Methodological differences are a fly in the research ointment.
Rat studies might have reached the end of their useful life here, because rats cannot report on their emotional states, and that is what emotional eating is all about. In lab experiments, rats get lard and sucrose, so there is not much range to explore in terms of whether it is something about the food itself that satisfies them, or just being fed.
Rats are not routinely tested on their reactions to salty foods, yet in the human comfort-food universe, some people prefer salt. What this team objects to is “the confounding of nutrient properties (such as carbohydrates) versus hedonic (such as sweetness) properties of food, either of which (or both) may be driving comfort eating effects.”
Back to humans
Conditioning is a huge factor. Is macaroni and cheese this person’s go-to comfort food because of properties intrinsic to the macaroni and/or cheese? Or because this, on long-ago sad rainy days, is what grandma provided? The report mentions a study (Wagner et al., 2014) that found comfort food affected the subjects’ emotional states about the same as no food. A 2011 study inserted gastric feeding tubes into people. Some got saline solution and some got fatty acids.
They found that those randomly assigned to receive fatty acids rated sad music and sad faces as less sad than those assigned to receive saline.
Sooo… fat has a cheering effect, at least under those conditions in that particular experiment. The authors point out an important detail which, on reconsideration of all kinds of past experiments, might cause some red flags to pop up. Here it is: Placebo pills are often sugar pills. If there is one thing we know, it is that sugar is not an inactive, inert substance.
Introducing another of their studies, the same team wrote,
[…] the effectiveness of comfort eating may be particularly relevant in the context of depression, but no study has tested whether comfort eating processes might depend on severity of depressive symptomology.
As things stand, not much is known about whether comfort eating ameliorates stress. These authors are positive that future research will require interdisciplinary cooperation between biologists and psychologists.
Sufferers from binge eating disorder and bulimia nervosa will probably not feel better, and in fact experience even more stress, because they feel guilt and embarrassment, which is definitely not comfortable. Attempting to discover whether comfort eating “works” on the depressed, the team looked at 2379 young adult women and found that…
[…] comfort eaters may experience lower levels of perceived stress compared to those who do not engage in this behavior, but this protective effect of comfort eating may not extend to those with elevated depressive symptoms.
So, maybe comfort eating “works” for some people, sometimes. And if only people could derive comfort from foods that are actually good for them, it might not be a bad thing. The report says, “it seems plausible that at least for some, it may be feasible to reduce perceived stress via comfort eating without simultaneously promoting weight gain over time.” Will therapists some day prescribe comfort eating?
Your responses and feedback are welcome!
Source: “Did That Brownie Do Its Job? Stress,Eating, and the Biobehavioral Effects of Comfort Food,” Academia.edu, 2015
Source: “Comfort eating, psychological stress, and depressive symptoms in young adult women,” DishLab.org, 07/17/15
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