3 Reasons Why Diets Don’t Work

Millions of people attempt and “fail” at dieting every year. Many think that they failed, that they just need to exert more “willpower,” when the truth is that the diets fail, not people. Our bodies are biologically designed to resist weight loss. In fact, scientific evidence shows that 95%+ of diets fail long-term, meaning that people re-gain most or all of the weight that they lost within five years.¹ It’s why the dieting industry is worth billions of dollars. 

Although this is starting to become more well-known, mainstream media platforms typically only associate this failure with “fad diets.” In reality, this applies to any type of food restriction. When we restrict our food intake, our bodies do not know that we are intentionally trying to shrink them. They recognize it as starvation – which to be fair, it is! This is a threat to our survival and our bodies are genetically hard-wired to survive. Therefore, they kick in a whole host of biological mechanisms to ensure that weight loss does not happen.

Let’s go over the top 3 reasons why diets don’t work.

1. Our Metabolisms Slow Down

Our metabolisms slow down. Our bodies are keeping track of all the energy coming in (food) and going out (movement). If it detects a shift in this balance, it slows down some of our bodies fundamental processes to preserve energy. This includes our cardiovascular system, digestive system, etc. So what does this mean for us? Our bodies will force us to slow down. This can manifest as fatigue, poor temperature regulation (feeling cold, especially in your extremities), constipation, and more.  

2. Our Bodies Make Us More Hungry

Our bodies make us more hungry. Restricting increases the production of Ghrelin, which is a hormone released from the stomach that makes us hungry and promotes food storage in the form of fat.² Ghrelin levels increase if we have not eaten in a while and decrease after we eat. Studies have demonstrated that dieting can cause a prolonged, elevated levels of Ghrelin.³ This results in frequent, often overwhelming, hunger and thoughts about food. For many, it can lead to overeating or binge eating, which is essentially, our bodies telling us, “either you can feed me willingly or I will make sure that I get what I need!”

3. Our Bodies Crave More Carbohydrates

Our bodies crave more carbohydrates. Restricting increases the production of Neuropeptide Y, which is a chemical messenger released from the brain that makes us want to eat carbohydrates. Why would our bodies do this? Carbohydrates are our bodies top choice of fuel. They can break down and use carbohydrates with ease compared to protein or fat. In fact, our brains, nervous systems, and red blood cells can only use carbohydrates for energy. ⁴ When our bodies do not get the carbohydrates they need, we may notice that we have difficulty focusing, feel fatigued, or feel irritable.

Speak with a Nutritionist

Beyond wasting our time, energy, and money on something that does not “work,” dieting can actually be physically and mentally harmful. We already established that most dieters will regain the weight they lost. However, it should be noted that up to 2/3 of dieters will gain more. In other words, they will weigh more than they did before starting the diet.⁵ Although diet culture may stigmatize this phenomenon, it’s actually protective. It’s our bodies’ way of ensuring that we cannot threaten our survival again.

Unfortunately, many people get caught up in weight cycling where they lose weight, then gain weight, then start all over again. Science tells us that this process actually increases our risk for cardiovascular disease and mortality. ⁶ This process, not the weight gain itself, is likely one of the reasons why we see the correlation between body size and certain health conditions.⁷ Furthermore, dieting is correlated with the development of eating disorders, increased stressed, and decreased self esteem. ⁸  

Courage to Nourish is a group of eating disorder specialized dietitians. We have in person locations in Alexandria, Virginia, Columbia, Maryland. and College Park, Maryland. We offer virtual services across the state of Virginia, Washington DC, Pennsylvania, and Colorado. We offer individual nutrition therapy. As well as support groups. We would love to guide you in building a better relationship with food.

Contact us for more information. And to schedule a discovery call. Also, sign up for our client or clinician newsletter!

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References:

¹ Christy Harrison, Anti-Diet: Reclaim Your Time, Money, Well-Being And Happiness Through Intuitive Eating (New York, NY: Little, Brown Spark, 2019), 85-87.
² “Ghrelin,” last modified March 2018, https://www.yourhormones.info/hormones/ghrelin/
³“Ghrelin,” last modified March 2018, https://www.yourhormones.info/hormones/ghrelin/
⁴ Evelyn Tribole and Elyse Resch, Intuitive Eating: A Revolutionary Anti-Diet Approach (New York, NY: St. Martin’s
Publishing Group, 2020), 88-89.
⁵ Christy Harrison, Anti-Diet: Reclaim Your Time, Money, Well-Being And Happiness Through Intuitive Eating (New
York, NY: Little, Brown Spark, 2019), 91.
⁶ Christy Harrison, Anti-Diet: Reclaim Your Time, Money, Well-Being And Happiness Through Intuitive Eating (New
York, NY: Little, Brown Spark, 2019), 144.
⁷Evelyn Tribole and Elyse Resch, Intuitive Eating: A Revolutionary Anti-Diet Approach (New York, NY: St. Martin’s
Publishing Group, 2020), 73.
⁸ Evelyn Tribole and Elyse Resch, Intuitive Eating: A Revolutionary Anti-Diet Approach (New York, NY: St. Martin’s Publishing Group, 2020), 73-74.

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