Why Diets Don't Work
Bottom Line Up Front:
Dieting is ingrained in our culture and diets are mostly geared toward weight loss. Unfortunately 90-95% of weight loss diets fail and most of the weight is re-gained or dieters gain more due to the restriction and off-set in our body.
Biologically speaking, when we diet or restrict our caloric/energy intake, our body reacts the same way it would during starvation or famine. Our body reacts by slowing down our metabolism, messing with our hormones, increasing stress, anxiety, and preoccupation around food. The more we diet, the more these effects take over and leave us with a slow metabolism, lack of hunger/fullness cues and hormones that are out of whack!
Your body has a natural set point and each person has a genetically pre-determined weight that their body is comfortable. The more you try to reach below your set point (unrealistic expectations usually due to societal pressure for an ideal body) - the more your body will react by trying to retain the weight and increase your set point.
My advice: Send a goodbye letter to dieting, treat your body with more kindness, and stop focusing on a number on the scale. Explore gentle nutrition and keep reading here and other non-diet RD blogs for ways to implement sustainable eating that is both satisfying and nourishing.
Now that it’s February and the hype of the “New Year, New You” diets, Whole 30, or 21-day resets are dwindling, it’s time to be realistic about sustainable weight loss and the influence of diet culture. Now before I start I want to be clear - it is OKAY to want weight loss and it is okay if you have tried diets (for some, numerous diets) to try and change your weight - it is ingrained in us. For decades, diets have plagued our culture - think Atkins, South Beach, Weight Watchers, 21-day resets, cabbage diet, grapefruit diet, Whole 30, Keto, Paleo, juice cleanses… shall I go on? It was estimated that in 2018, the diet industry was profiting almost $70 billion dollars in the U.S and we are spending more than ever to try and lose weight and succumb to an idealized perception of a health and thinness. And yet, if you are someone who has tried dieting before (I think most of us can raise our hand here), you probably have lost weight, re-gained, or even gained more than before. Why? Because diets do not work and 90-95% of diets resulted in weight regain and two thirds of those people will gain even more weight than where they started. In fact, a review of 31 studies showed that going on a diet is a predictor of weight gain.
What constitutes a “diet?”
There are several definitions.
A diet is the kinds of food that a person, animal, or community habitually eats.
A diet is necessary for medical reasons - for diabetes, gluten-free for those with celiac or gluten intolerance, low-lactose for those who or lactose intolerant, DASH diet for hypertension, etc.
The diet that restricts oneself to small amounts or certain types of foods to lose weight. This is the diet we will be discussing here.
What happens in our body when we diet?
Slowed metabolism: When we begin to lose fat stores, our body secretes a hormone Leptin, which goes to the brain and signals that we are losing fat. In response, our brain sends signals to our muscles to stop working as efficiently and stop burning as many calories to hold on to the fat we still have.
Alteration in hormones/body signals: Your body releases chemicals to make you think about food (specifically the chemical NPY) which increases your desire for food, decreases satiety (fullness) and simulates food intake. In addition, Ghrelin (a hunger hormone) is increased and Leptin (a satiety hormone) is suppressed - causing an alteration in our hunger/fullness cues.
Increased consumption of food (binge): Our brain increases its reward/pleasure response for foods that are restricted. Think of “forbidden foods,” when they are forbidden - we want them more. BUT… that is just a natural response in our brain to restriction, not us being “bad.” Diets often tell us to fill up on fruits/vegetables, drink more water, chew gum to suppress appetite. The more we do to restrict and ignore our hunger, the more likely we are to binge.
Increased preoccupation with food: diets often make us obsess over food and things related to food. A 1940s study, The Minnesota Starvation Experiment, conducted on 36 men aimed to assess the effect on caloric restriction. In the experiment, they cut the mens’ caloric intake in half for six months. Among other effects, their psychological state was affected significantly. The men were obsessed with food, food images, reading, talking about food. In reality, dieting often leads to disordered eating/thoughts and eating disorders.
Set point/weight regain: With high stress levels, our body continues to set the stage for weight gain outside of our predetermined range. Our body favors a specific weight. This is the set-point theory which states that our bodies have a predetermined, genetic range of weight with a range of 15-20 pounds. We likely regain the weight, and the more we diet and yo-yo in these weight cycles, the more weight we gain and more our body moves away from it’s natural set point.
Dieting and any form of restriction is un-natural and is proven to actually back-fire and be a predictor of weight gain. In addition, it can cause a preoccupation and obsession around food and nutrition, cause bingeing, alteration in our hormones and signals, and slow our metabolism. Think of chronic-dieters - they know every measuring cup, portion size, nutrition fact and label, etc. The amount of time spent on dieting and obsessing over food is actually having a biological effect in our body.
What you can do? First up is to reject the diet mentality (you’re doing great - you read this post!). Realize that dieting is an industry feeding off your hard-earned money. That your body is amazing and it is designed to keep you healthy and at your natural set point. That fighting your weight will only lead to unwanted consequences and likely weight gain.
Be kinder to yourself and realize YOU don’t fail a diet - the diets fail you.
An amazing resource I highly recommend is Intuitive Eating by Evelyn Tribole and Elyse Resch - a great introduction into normal eating and how to become an intuitive eater. Another great one is Body Kindness by Rebecca Scritchfield, I am still reading through but feeling empowered already.