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How Fad Diet Psychology Can Cost You Your Health

Three hidden reasons to be extra cautious of the latest fad diet.

Key points

  • Fad diets can become more sensationalized to compete with each other.
  • Fad diets often emphasize new, exciting, and unfounded interventions at the expense of basic healthy eating.
  • Fad diet marketing often relies on emotional appeals instead of scientific evidence.
Thought Catalog/Unsplash
Source: Thought Catalog/Unsplash

Take a poll of Americans today and you’re likely to find a lot of confusion about how to eat for good health. In fact, in a survey published in 2017, nearly two-thirds of younger Americans said they doubt their food choices because of conflicting ideas on what constitutes a “healthy diet.” This lack of consumer clarity stands in stark contrast to diet gurus proclaiming they have cracked the universal code to perfect health. But even if we splinter into clans or “food tribes,” in an attempt to follow these “experts,” by and large we are let down. One often-overlooked reason: we fail to consider how marketing psychology influences dietary design. Here are three key examples to help you understand where we’re being led astray.

1. Fad diets are trapped in a race to the bottom

In economics, a race to the bottom is when companies undercut each other’s prices at the expense of quality. Applied to diets, this principle helps explain the psychological maneuvering and broken promises characterizing many fad diets today. In essence, competition between diets can require their respective leaders to perpetually up the ante on what they say their diet can deliver, despite a lack of substantiation. When health expert A states that his diet will make you lose 10 pounds in a month, expert B then has to claim hers will get you to drop 20 pounds. When expert A proclaims his diet will fix your heart disease and diabetes, expert B decides hers does all that and treats depression and cancer. This downward spiraling widens the gap between a dieter’s expectations and reality, leading to inevitable letdowns and a likely loss of trust in the efficacy of dietary change.

2. Fad diets have an opportunity cost: basic nutrition advice

It’s been consistently demonstrated that simply eating more real foods (instead of the ultra-processed standard American diet) is of benefit to people’s health. And in fact, many popular diets today actually do recommend that participants avoid processed foods in favor of more whole foods. Unfortunately, this message has far less marketing cache than promoting a miracle superfood or removing a hidden “toxin” that is keeping you from losing body fat. Because diet gurus are competing for the same customers in a saturated marketplace, they’re much more likely to promote sensationalized messaging while bashing other diets than spend time describing the benefits of simple dietary changes. In this scenario, the people (arguably) best situated to educate others on the core, substantiated aspects of a healthy diet are led to instead focus on the extremes of their diet plan, protecting their brand and marketability instead of promoting general healthy eating tenets that would have the greatest net benefit.

3. Fad diets leverage emotion over science and reason

In theory, the science behind a diet’s efficacy should be the most important consideration. But too often science and rationality fall by the wayside as emotionally charged claims take center stage. We’ll watch a clip of one person’s dramatic weight loss journey on a new diet, see them crying in gratitude and then decide to embark on the diet ourselves. The diet expert points at us from the TV screen and tells us that we can change our lives and lose the extra weight today. And of course, unless we act right now, we’re going to miss this once-in-a-lifetime opportunity. Our emotions are triggered. We feel inspired and excited for our assured success. We feel scared that we will miss out. Activation of emotional brain networks makes us feel the diet is right for us while simultaneously causing us to gloss over the more important question: Is there any good evidence that this diet actually works? In the midst of this feeling, we order a subscription to a meal plan or sign up for a dietary coaching group that never gets us to our goal.

What to do with this information

Let’s be clear: changing our diet is hard work. Our society is set up so that unhealthy foods are the default options, and there are many incentive structures keeping us from choosing real, nutritious unprocessed foods. On top of this, we have to deal with the widespread availability of unscientific diets heavily influenced by marketing psychology. This all means it’s essential for us to have a more critical lens through which we view new diets. And while many alternatives have been suggested to counter the deluge of fad diets, one logical plan is to switch focus. Instead of trying to find the next quick-fix diet, look to cultivate a sustainable and enjoyable pattern of eating that centers on whole food and minimally processed ingredients eaten mindfully.