Why Most Dieting Advice Fails

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As professional fitness trainers, we’ve either heard the same dieting advice or have been guilty of repeating these maxims over and over again.  

“Eat less and move more.”

“Everything in moderation.”

“Calories in, calories out.”

They are not working.

Not because they are untrue. Though these common weight loss phrases are born of science, they prove ineffective to the average client with weight loss goals. There are several reasons why this seemingly good advice has been inadequate in the face of increasing rates of overweight and obesity:

  • They do not address the underlying neuroregulation of appetite
  • They do not address an individual’s circumstances
  • They oversimplify the complex emotions and biological processes involved in a person’s relationship with food

“Eat Less, Move More” Goes Against Our Biology

As one of the core reasons for why people differentiate dieting behaviors from “normal” eating behaviors, Optimal Foraging Theory accounts for the unconscious drivers of our eating habits. This theory states that an animal will seek out food with the most energy (calories) for the least amount of energy expenditure (work).

Telling an individual to eat less and move more is advice antithetical to our biological drives. From an evolutionary perspective, the argument could be made that if a person today isn’t obese, diabetic, and constantly eating highly-processed, calorie-dense food, they are doing something wrong!

This advice, while contradictory to our nature, should serve to illustrate how our modern lifestyle is at odds with the world in which our bodies were designed to live. Our genes did not expect us to live in a time of such abundance and convenience. Acknowledging that we are fighting against an innate drive is paramount in overcoming this obstacle to weight loss.

Moderation is Subjective

“Everything in moderation” is usually brought up in the context of allowing occasional indulgences. While the phrase may bear some truth, it does not factor in the emotional or environment triggers related to indulgences. It’s common, especially around the holidays, for friends or family to pressure a someone trying to lose weight into indulging in certain foods that he or she has been trying to avoid or abstain from.

Objectively, this should not be an issue as long as total calories are kept in check. Emotionally, however, this can cause a massive release of dopamine, which can create an environment in which the client can easily slide into a binge. In her book Food Freedom Forever, Melissa Hartwig uses the language of addiction to discuss food choices. This is may be the most appropriate way to frame an emotional relationship with food, as many people exhibit behaviors that, if it were any other substance, would be described as addiction.

For someone who has a predilection for eating salty carbs, having chips in the cabinet might tempt her to eat the entire bag in one sitting, while another without the same desire could have a handful and be done with it. This highlights how moderation is subjective and can vary from one person to another. Some people can indulge on occasion and be fine, while for others it’s best to abstain entirely. Ultimately, it’s up to the individual to decide what constitutes moderation in pursuit of their goals.

Calories In/Calories Out Is Incomplete

Being in a calorie deficit is the only scientifically proven way to lose fat. Counting calories is proven again and again to help people lose weight. Keto, Paleo, Low-Carb, Vegan, Vegetarian, Mediterranean, DASH, and WeightWatchers help people lose weight because they all incidentally (or purposefully) create a calorie deficit. Individuals who utilize any of these approaches and successfully lose weight do so because they are able to stick with their chosen dietary approach.

Keto, Paleo, and Low-Carb diets remove highly-processed, high-sugar foods from a person’s diet. Vegan, vegetarian, Mediterranean, and DASH all reduce fat from a person’s diet. WeightWatchers rebrands calorie counting as “points”, and gives its members discretion as to how those points are spent. They all work for weight loss, and it’s up to the individual to try a variety of approaches in order to figure out which one works best for them.  

Adherence to a particular approach while maintaining a calorie deficit is the best predictor of weight loss. Some people find eliminating food groups an easier way to stick to their plan. Other people find it best for their mental health to be more flexible with their food choices. The mental and emotional toll habit change takes cannot be overlooked when it comes to weight loss. It will never be stress-free, but trainers can help their clients find a dietary approach that causes them the least amount of stress, which will often lead to consistent adherence and better overall results.

The Takeaway

Popular diet advice fails because it fails to address the complexity that is inherent in weight loss and behavior change. Mental and emotional barriers must be overcome if an individual is going to be successful at losing weight, especially if he or she has been overweight or obese for some time. The work of addressing these deep-seated, emotional subjects can feel frightening and uncomfortable. It’s important to cultivate judgment-free relationships with your clients that make them feel safe to talk about these underlying drivers of behavior.

Empathy and accountability are not mutually exclusive, and it can be a difficult task to walk the line between the two. Yet, if you can help your clients believe in themselves and in their ability to change, you can help them break through their barriers and flourish in a way they may not have thought possible.

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David Rodriguez is a graduate of the Personal Trainer Certificate Program at San Diego Mesa College, an NFPT and ACE Certified Personal Trainer, and Certified Fitness Nutrition Specialist. David was inspired to become a personal trainer after losing more than 100 pounds. Having kept the weight off for over a decade, he uses his story to motivate his clients and demonstrate to them that big changes are possible and sustainable. His training focuses on pain-free movement, helping clients find an individualized nutrition plan, and creating a positive mindset. His favorite pastimes are soccer, weightlifting, hiking, cooking, and his dogs. David lives in San Diego.
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