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Are We Stupid to Make Dieting a New Year’s Resolution?

Why long-term dieting success is so difficult.

It’s that time of year again. You’ve reveled your way through December, and now you’re feeling guilty about your excesses and upset that your jeans feel too snug. It’s January 2020, a new day, a new year, a new you, and this time—no more junk food! Or so you promise yourself.

According to a digital poll conducted by the Insider at the end of 2018[1], nearly 50 percent of New Year’s resolutions are about dieting or healthier eating, yet the evidence shows that by the ​second week of February 80-90 percent​[​2], of these resolutions have failed. Why do we keep making well-intentioned resolutions about restricting our intake of fatty, sugary foods, and then consistently relapse? Are we stupid to continuously make such futile promises?

Sisyphean attempts to change our eating behaviors suggests that we’re not very good at learning. But that nod to our foolishness would be to gloss over the problems underlying why we push that rock up the dieting hill every January only to have it roll down on our thighs by Valentine’s Day. There are three main reasons for our repeated dieting failures:

  1. habits
  2. the food environment
  3. our biology.

And they’re all extremely hard to alter.

First, our well-learned habits. Do you make a daily stop for a pastry or milkshake latté on your way to work? Do you mindlessly snack at your desk? Do you automatically say “yes” to fries with that sandwich?

To change our eating behavior, we first have to figure out what our “bad” eating habits are, which is not so easy. Then we have to break the mold on all those automatic routines. This means crushing habits from breakfast to our midnight snack, at home, work, and play.

Put this in the face of the central reason why changing behaviors so often fails: people try to change too much at once. For best success, we need to make a list and slowly tackle one bad habit at a time. This itself is a tedious task, which only adds to the burden of restricting our eating. Eating is among the greatest pleasures of existence, and we have to do it fairly constantly. This means that if we make eating unpleasant, we won’t give up eating; we’ll give up making it unpleasant.

Next is our perilous food environment. Even if you don’t have much money (in fact, it’s worse if you don’t have much money) unhealthy food is more accessible than fresh fruit, vegetables, and fish. Western eating offers a plethora of relatively inexpensive, high-calorie, delicious options with very minimal effort involved in getting any of it. You don’t even need to leave your couch except to answer the doorbell for that UberEats delivery.

There is a large scholarly literature on everything from portion size, to fast food availability, to how we eat (constant snacking, eating on the run or in your car), and how much we eat (a lot) and you will find many studies demonstrating the ways in which the modern eating environment undermines our health and waistlines. But you already know that. The point: The "new normal" food environment makes changing our eating patterns, portions, and passions very difficult to thwart.

Finally, there is our innate biology. We did not evolve in a landscape of Starbucks and MacDonald’s. Rather, until relatively recently, having enough food to eat was a rare luxury, and there are still societies where famine is a real and present danger.

Because we may have to go for days, or more, without sufficient sustenance, when we encounter calorie-dense foods—the best kinds are fatty and carbohydrates, the best form of easy energy—our biology dictates that we eat as much as we can so that we can survive to find the next meal. We are programmed to love fatty, high-carbohydrate foods​. To counteract these impulses ​is to work against millions of years of evolution.

​Our food habits rewire our neural circuits for pleasure and reward, our food environment reinforces our food habits, and our innate biological motivations shape our enabling food environments. Yes, we are stupid to think that intoning a promise to eat less rich, alluring food when faced with such huge obstacles will be successful. But we are not stupid to keep​ on trying, ​because ​each attempt teaches us about ourselves and potentially brings us one step closer to a better relationship with food.

The key is to realize that at the heart of both our “good” and “bad” eating behaviors is the motivation to survive and experience pleasure​,​ ​which is smart indeed.




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