According to national surveys conducted by the American Psychological Association, the majority of Americans report moderate to high levels of stress. Though the prevalence of full-blown anxiety disorders hasn’t changed much over the last few decades, the level of general psychological stress appears to be getting worse. After following thousands of people and their stress levels over time, there does seem to be a connection between stress and modest weight gain. In fact, the increased risk of diabetes in veterans with post-traumatic stress disorder (PTSD) may be explained by the link between PTSD and weight gain. Effects on both sides of the calorie-balance equation have been used to explain the stress-obesity relationship.
For many who are stressed, structured exercise may be viewed as a disruptive inconvenience, just one more demand on their time, and indeed, the majority of observational studies have found that stress is associated with less physical activity. Stress may also reduce the thermic effect of food and reduce how much fat is burned after a meal. In one study, those reporting a stressful event the day before testing burned about one hundred fewer calories in the six-hour period after eating compared to days not preceded by anything particularly stressful.
People who are stressed may eat more too. Though some people eat less when stressed, the majority not only eat more, they tend to gravitate toward foods high in sugar, fat, and calories. If you give people their own private snack buffet, those with high chronic stress levels eat less fruits and veggies and more chocolate cake. We suspect it’s cause and effect because you can demonstrate the acute effects of stress in a lab. Randomize people between solvable and unsolvable word puzzles, for example, and food choice shifts from a healthy snack (grapes) to a less healthy snack (M&M’s) in the more stressful condition. The stress of public-speaking challenges or being made to plunge and keep your hand in ice water has been found to dull your ability to sense sweetness, tempting you to eat more to achieve the same taste. Even just watching a video with distressing scenes, including traffic problems, financial hardship, and sexual harassment, can evoke the same shift in eating behavior toward chocolate.
They don’t call it a comfort food for nothing. Overeating may be a sign that something is eating us.
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Mindfulness is a major part of the billion-dollar meditation industry, with as many as one in five Fortune 500 companies implementing some kind of workplace mindfulness program. It has been rebranded from “hippy dippy nonsense” to portrayals such as “brain training” said to “sell it better.” These reductionist, commodified forms have been derided as “McMindfulness,” but who cares what they call it if it works? But does it?
Research into mindfulness has been complicated by the fact that the term can mean anything from informal practices, such as conscious awareness while eating, to structured meditation programs involving designating set times to sit in a specific posture attending to your breathing, for instance. This has made an understanding of the efficacy hard to capture. It can’t hurt, though, right? Well . . .
There have been more than twenty observational studies or case reports documenting instances of adverse effects, such as meditation-induced psychosis, mania, anxiety, and panic. One study at an intensive meditation retreat assessed participants’ negative experiences since they had begun meditation. They found that seventeen of twenty-seven participants—more than 60 percent—reported at least one adverse effect, including an individual who was hospitalized for a psychotic break. Even outside of an immersive retreat environment, as many as 12 percent of meditators recall negative side effects within ten days of initiating the practice.
It’s considered plausible that adverse effects occur at rates approximating that of psychotherapy, with about one in twenty patients reporting lasting negative effects of psychological treatment. With about twenty-five million Americans practicing meditation and as many as a million new meditators a year, even a 5 percent adverse-event rate could mean hundreds of thousands of negative side effects a year. As with any medical intervention, though, it’s all about risks versus benefits. Unfortunately, many of the benefits have been overstated.
A commentary in a psychiatry journal entitled “Has the Science of Mindfulness Lost Its Mind?” notes that even the books on mindfulness written by scientists are “bursting with magical promises of peace, happiness and wellbeing.” Contrary to the popular perception, however, the evidence for even the most well-founded benefits is not entirely conclusive. This is not an issue unique to meditation. There is a “replication crisis” across the entire field of experimental psychology, where many of the landmark findings in the social sciences published in even the most prestigious journals don’t appear to be reproducible.
Drug companies aren’t the only ones to suppress the publication of studies that don’t come out the way they wanted. The majority of mindfulness-based trials apparently never see the light of day, raising the specter of a similar publication bias. Presumably, if the studies showed promising results, they would have been released rather than shelved. What’s more, many of the ones that do make it into the scientific record are underwhelming. The federal Agency for Healthcare Research and Quality published a systematic review of the available data and concluded that mindfulness meditation worked best for improving anxiety, depression, and pain, but even then, the quality of evidence was only “moderate.” What about weight loss?
Mindfulness-based modalities can help with stress management and self-control, and can decrease impulsive, binge, and emotional eating, all of which might facilitate weight management. However, the first review of the available evidence published five years ago failed to find evidence of significant or consistent weight loss. Part of the problem is compliance.
Like any other diet or lifestyle intervention, mindfulness only works if you do it.
For instance, women were randomized to attend four two-hour workshops that taught mindfulness techniques such as cognitive defusion. After six months, they lost no more weight on average than the control group. However, if those who reported “never” applying the workshop principles at all were excluded and only those who used the techniques at least some of the time were considered, their weight loss did beat out the control group by about five pounds.
Other studies showed a lack of weight gain rather than loss. For example, one study found that obese subjects in the control group continued to gain weight at about a pound a month, whereas the weight of those in the mindfulness intervention group remained stable.
Putting all the studies together, the latest and largest review published in 2018 did find that mindfulness-based interventions can lead to weight loss compared to doing nothing, an average of about seven pounds over four months or so. Pitted head-to-head, however, they didn’t beat out other lifestyle-change interventions, but the nice thing about stress management and mindfulness is they can be practiced on top of whatever else you’re doing.