A scientific exploration of why weight-loss diets may actually do more harm than good
When I first started my career as a Dietitian, I was deeply indoctrinated into the Dieting Paradigm. The health perils of being overweight had been drummed into me at university and I started my profession thoroughly convinced that weight loss diets were the panacea to our obesity epidemic.
Today, after working with thousands of clients, wading through indomitable mountains of research and embarking on my own food journey, I am willing to face the reality that diets don’t work.
Contrary to popular belief and the words of self-flagellation that I’ve heard from the mouths of countless clients, the general inefficacy of weight loss diets isn’t due to a “lack of willpower” or “laziness”. I (and many others) posit that diets are inherently flawed, that YOU don’t fail at diets, rather DIETS fail you.
If you’ve been sold the Diet Myth, as most of us have, then this assertion may sound crazy. But if there’s some part of you that recognises that diets haven’t been helping you, and don’t seem to be solving other people’s problems either, then keep on reading.
This essay is an exploration of the science behind what most of us can intuit; that in the long term, diets don’t work.
A Short History On Dieting
Diets are not a new phenomenon. Ask your mum and she’ll tell you; diets have been around for decades.
From no fat to no-carb, the diet industry and media have been spoon-feeding us the same message – to be healthy and beautiful, we must lose weight, and to lose weight, we must diet! In my practice as a Dietitian, I have encountered women who have tried every commercial weight loss under the sun.
These ladies can rattle off their past diets like a litany of lost dreams. And whilst the nuances of their diet stories may differ, the core threads are the same and go something like this;
Women doesn’t like her body and wants to be thinner
Women goes on [insert name of current weight lose fad] to lose weight
Women loses weight (initially)
Women can’t sustain restrictive eating patterns prescribed by diet and develops disordered eating behaviours
Women regains weight (plus a few extra kilos)
Women doesn’t like her body and wants to be thinner
Cycle starts all over again.
This cycle can go on for decades, each time stealing a little bit more a woman’s self-esteem and condemning her relationships to food and her body. If you can relate to the cycle (as I sure can), then please know that you are not alone.
The statistics are utterly staggering. The last 30 years of diet research indicates that 95% of diets fail within a five-year period. Let me repeat: 95% of diets fail within five years.
Not exactly something you will read on any diet advertising! Diets are beguiling because they tend to work in the short term. Y’know that feeling during the first few months of a new diet program; motivation is fresh, you’re losing weight, feeling great and the compliments are rolling in. It’s seductive.
Yet inevitably, birthdays, Christmas and ‘stuff’ pops up that our diet doesn’t cater for, old habits start creeping back in and before we know it, we’ve fallen completely off the wagon. Hello, square one!
This is not a unique situation. For most people, 30-60 % of lost weight is typically gained within the first year of dieting and almost all weight is regained within a five year window. Studies show that 30% of clients typically put on more weight than they originally lost (Dulloo & Montani, 2015).
Sure, we all know of somebody who’s done well on a diet, a real ‘success story’. This isn’t an attack on anyone who genuinely benefits from dieting. Good for you! However, my deep concern is that these success stories are the exception.
The rule is that dieting does not work for most people and after 30 years of plugging the ‘get thin and diet’ message, I think it’s time to get real about it and find approaches that stand a real chance of actually helping people.
The Dieting Paradox
If one starts looking closely at the current state of health and weight trends, any claim to dieting efficacy starts to unravel pretty quickly.
Today, almost two in three Australians are overweight or obese (AIHW, 2018), which is an all-time high in human history. Yet paradoxically, up to 46% of Australians also report being on a diet or trying to lose weight, a trend that’s also at a historical peak (Dietitians Association of Australia, as cited in Clemons, 2017).
If diets solved our weight problems, and half of the population is currently on one, shouldn’t half the population be getting leaner?
Or shouldn’t we at least see an attenuation of our rising national weight trajectory?
Instead, the picture is moving in the OPPOSITE direction.
Whatever the underlying reasons are and whether dieting is a contributing cause or merely a symptom of weight gain, diets are clearly not getting to the root of the problem or providing any real solution to obesity. Despite an unprecedented volume of people dieting to drop weight, the average Australian is gaining weight at a velocity of one kilogram per year (The Department of Health, 2009).
Restriction = Overcompensation (Why Caloric Deprivation Can Lead To Overeating)
If you believe current archaeological evidences, humans have inhabited this planet for anywhere up to 200,000 years. For the vast majority of this time, we were throwing spears and tracking antelope as hunter gatherers. In our primordial environment, we had none of the food luxuries afforded to us by modern society today. The world was a wild place and tests for survival were harsh.
Throughout history, our ancestors would have faced extreme climatic changes and times of food scarcity. Famine would have been a very real threat and the survival of our species depended on the human body being able to withstand periods without food. As such, the human body is very well evolved and equipped to deal with starvation. Understanding how the body and mind operates during starvation gives us essential clues into the intrinsic fallibility of dieting.
During times of hunger, a number of amazing things happen to our body and mind. (Macpherson-Sanchez 2015). These mechanisms are built into our primal DNA and remember; our genes can’t distinguish between calorie deprivation due to diet or calorie deprivation due to genuine famine. Your body’s job is to simply protect you from starvation at all costs, no matter the situation.
What happens to the body during dieting and (semi) starvation:
1. Firstly, when humans are plunged into calorie restriction – whether from enforced starvation (i.e. famine) or voluntarily (i.e. dieting) – our metabolic rate drops. It’s like running on power-saving mode and the body knows how to conserve energy. After all, your body doesn’t know if you are on the Atkins Diet and intend to eat another 500kJ in three hours’ time. Its job is to simply recognise when energy in is less than energy out, and to make the fuel we’ve got last as long as possible. Thus, the body burns less calories.
2. Secondly, when we’re calorie-restricted, we also feel hungry. If you’ve been trying to lose weight or diet, chances are that you may experience hunger as exasperating at best, or miserable at worst. Many of us battle with our appetite as though it were an enemy. But that’s like fighting against your heartbeat or hating your lungs for breathing – it’s futile. Our appetite is a normal bodily function that helps us to gauge how much food our body needs to remain fuelled. During dieting (and perhaps as humans today living in a new, obesogenic environment) this natural mechanism is ignored. Many of us oscillate between two extremes; we either overeat or we overly restrict our eating. Nevertheless, the fundamental point remains that hunger is a primal urge that is difficult to ignore.
3. Thirdly, when we’re hungry (or hangry) it affects our mood. Hunger can make us cranky, irritable, emotional or fuzzy-headed and yet we ‘will’ ourselves to overcome it. The thing is, ‘willpower’ is a psychological apparatus reserved for short-term efforts and hunger is not something we can ‘think positive’ to override.
4. During dieting, our body tends to breakdown muscle tissue preferentially to fat tissue, which exacerbates our drop in metabolic rate. You see, when we’re not consuming enough calories from our food, the body taps into its own stores (liver glycogen, tissue, then organs) for energy instead. Your body literally eats itself! However, it does so strategically and its game plan hinges on glucose.
Glucose is a bit like Grade A Premium fuel for the cells in our body. It is an efficient, effective substance for cells to convert into energy. The breakdown of muscle tissue provides a lot of glucose, which our cells love to use. On the other hand, whilst fat tissue breakdown provides some glucose, the primary fuel provided by our fat stores is ketones. Ketones are like Grade B Inferior fuel for your cells; it’s not quite as readily used. Whilst there are dietary strategies that can mitigate the loss of lean body mass, the reality is that most people will find it difficult to lose weight without losing muscle.
5. The human body is wise beyond words. To me, one of the most fascinating aspects of starvation is what happens in the end stages. The body will breakdown organs in preferential order of least importance to derive calories. The body chooses the least essential organs to break down first, with vital organs deteriorating last. Your digestive tract is the first to go (if you’re not eating, who needs intestines?) with the spleen, liver and kidneys somewhere along the middle of the road, and your heart and brain protected until the final stages of starvation. Simply remarkable.
Dieting & Weight Gain: A Chicken Or Egg Scenario?
There’s always another side to the story. According to some researchers, dieting is simply a proxy rather than cause of weight gain (Lowe). This school of thought asserts that dieting behaviours may be prompted by weight gain that individuals want to halt or rectify. Therefore, ‘dieting’ may merely be a symptom of an existing susceptibility – whether genetically, environmentally or psychologically – towards weight gain. In other words, some people were always going to gain weight whether they dieted or not and being on a diet had nothing to do with their weight trajectory.
This however is a very difficult theory to test, as it is impossible to retrospectively discern the difference between post-dieting weight gain and a person’s natural weight gain. Dieting, in effect, occludes their natural weight trajectory. In other words, it’s a Sliding Doors scenario – how can we know for sure what would have happened to a person’s weight in the past if they never decided to diet? No study on Earth can time travel to answer that question for sure. And the science nerd in me is uncomfortable with speculative theories.
In my view, the evidence on the other side of the fence and what we do know about the risks of dieting are far more convincing than hypothetical postulation.
For example, athletes involved in sports whereby weight cycling is common practice are at far higher risk of long-term weight issues than athletes who don’t routinely weight cycle throughout their careers (Dulloo & Montani, 2015). This is quite a compelling argument that dieting – albeit through intense fasting and weight cutting – may contribute towards long-term weight gain.
Furthermore, twin studies have also shown that dieting practices in ‘normal weight’ people are associated with weight gain, regardless of genetic, social and other variables in the environment (Dulloo & Montani, 2015).
As you can see, there are very plausible physiological reasons why diets may induce weight regain. Let’s take a deeper dive into what’s happening at cellular level to cause this.
Potential Physiological Mechanisms Driving Weight Regain After Dieting
1) Famine (i.e. dieting) and post-famine refeeding may result in unfavourable changes to fat mass and lean body mass composition. Loss of muscle and fat can create feedback signals that mediate weight regain due to effects on energy intake and adaptive thermogenesis. Furthermore, upon refeeding, fat mass recovery tends to occur at a faster rate than lean body mass, culminating in a post-diet body composition with greater muscle depletion and higher adiposity.
CLIFF NOTES: When we diet, fat cells undergo metabolic changes that make it easier for them to ‘suck up’ extra energy and convert it to fat when the diet’s over and we resume normal eating.
2) White adipose tissue is biologically primed to recover weight after weight-loss. Furthermore, the diminished size of adipocytes (fat cells) triggers metabolic changes that prepares fat tissue for fast storage of energy during refeeding.
CLIFF NOTES: After dieting, we tend to regain more fat than muscle.
3) Monocarboxylate Transporters (MCTs) help energy substrates to enter cells and also sense levels of available fuel and energy in their metabolic environments. MCTs, in addition to their substrates, have been implicated in many aspects of body weight regulation and metabolism. Systemic levels and activity of MCTs may be modulated by calorie deprivation and refeeding, potentially explaining adaptation towards weight regain post-dieting. Regaining weight after a diet may make you lose muscle and gain extra fat. Muscle is good for your metabolism, so having less of it drops your metabolic rate, making it easier to put on more weight in future.
CLIFF NOTES: The body contains tiny transporters that read how much energy is available to cells and get energy into cells when it is needed. During dieting, there are changes to the quantity and activity of these transporters, which may help to explain why the body easily regains lost weight when the diet is stopped and normal eating resumes.
As you can see, being on a diet triggers some pretty powerful changes to our bodies. But what you may not realise is how it can also affect our mind.
The Psychological Effects Of Hunger: Why Being On A Diet Can Make You Crazy About Food
Let me preface this topic with a small exercise.
I want you to pause for just 10 seconds right now and really ponder – if you could eat anything in the world at your next meal, what would it be?
Fancy that you could go and make that meal for yourself. It would feel pretty satisfying, right?
Now, what if I told you that after today, you could never eat chocolate? Presuming you like chocolate, as most people do, you’d probably go cocoa-crazy all-day long. And rightly so.
This simple exercise is designed to highlight what happens when we place a scarcity mindset around certain foods and eating. The psychological reflex is to want it more, regardless of what your body really feels like eating. This may apply to certain foods that you ‘ban’ on a diet, or it may simply apply to all food as a whole.
When you restrict calories, which is par for the course during dieting, you may find yourself obsessing about food and what you want to eat. You may fantasise about your next meal and clock watch until the next time that you’re ‘allowed’ to eat again.
As anyone who is dieting can attest, when we’re hungry it is difficult not to think about food! We literally have ‘food on the brain’ until our appetite is satisfied. This psychological rumination about food provides impetus for us to seek out food.
Once more, this may relate back to our caveman days. Although researchers can’t know for sure, one theory states that food fixation may be another primitive mechanism to protect against starvation. After all, if we’re not eating enough, thinking about food is one way to prompt us to go out in search of it. Back in our caveman days, when leaving the shelter of our cave to chase down wild game would have involved effort, thoughts of food realistically would have provided motivation to go out in search of it. Our biology hasn’t caught up to modern changes in food affluence.
Regardless of the mechanisms driving it, this preoccupation with food after periods of low food intake is widely discussed in the scientific literature (Dulloo & Montani, 2015). In fact, the correlation behind dieting and compensatory overeating is so strong that dieting has been linked to binge eating, disinhibition around food and even full-blown eating disorders (Dulloo & Montani, 2015).
It’s a vicious cycle. Firstly, we feel dissatisfied with our body, so we turn to a diet to lose weight. During this diet, we are deprived of calories and joyful food. Physiological and psychological mechanisms kick into gear to protect us against perceived starvation. We fight it for a while, ‘willing’ ourselves to override our hunger cues and stick to the diet. For most of us however, this leads to blowout; disinhibited eating, compensatory overeating or even a binge. The result? More weight gain and deeper body dissatisfaction. Yet despite the fact that the diet didn’t get us the results we want – and may even have made things worse – we’re lured by more false dieting promises and the cycle starts all over again.
Worryingly, the overcompensatory eating effects of dieting may not be merely short-term. In one published famine study, four men still struggled with excessive eating, binge-eating disorder and food cravings five months after they terminated a period of semi-starvation. Other studies have also described binge-eating as a post-starvation response, which may also explain weight rebound as a physiological recovery from food deprivation (Macpherson-Sànchez, 2015).
In short, dieting ignites a cascade of physiological AND psychological changes that are inherently designed to defend the body against starvation. Part of this defence system involves ensuring that the body’s diminished energy reserves (i.e. fat tissue) are restored and that the mind is sufficiently motivated to seek out food.
Never forget that our biology is primal. The body is very, very well protected against starvation. Therefore, saying that ‘losing weight’ is simply a matter of individual willpower is deeply insensitive and ignorant to the physiological constraints that are written into our very DNA. To make real change, we need tools at our disposal that take this into account, and are as powerful as the inherent evolutionary obstacles we face.
The Potential Health Risks Of Weight Cycling And Yo Yo-Dieting
Research shows us that weight regain after dieting may present concerning news for our health. “Overshooting” with weight gain after dieting (i.e. putting on more weight than we started with) can cause changes to our heart rate, blood pressure, blood glucose levels, insulin modulation, blood lipids (fats) and sympathetic activity, that collectively puts extra strain on our cardiovascular system.
Furthermore, dieting, weight cycling and “Yo Yo Dieting” has been shown to increase risk for eating disorders, anxiety and depression (Dulloo & Montani, 2015). Furthermore, weight cycling has also been associated with:
o Declines in cognitive function,
o Higher risk of diabetes, high blood pressure and certain cancers,
o Lower bone density,
o Higher overall risk of mortality,
Yo Yo dieting may also suppress the immune system. In a study of 114 overweight but otherwise well women, more than one weight loss episode of 10 pounds or more in the last 20 years was associated with lower natural killer cell function (Fred Hutch, 2004). Natural killer cells are an integral part of the immune system, involved in fighting cancer cells and viruses. Women who had lost significant weight more than five times in the previous twenty-year period had approximately 30% lower natural killer cells than their more weight stable peers. Crazy, right?
An important thing to note here is that it’s not just overweight women who are dieting. A significant amount of “normal-weight” women diet and there is a disturbing upward trend in this otherwise healthy population (Dulloo & Montani, 2015).
Risks for metabolic disease seem to be highest amongst normal weight populations engaged with dieting efforts that result in weight cycling (Dulloo & Montani, 2015). This means that it is essential, imperative and potentially even life-saving to support girls in loving their bodies more; particularly girls at risk of experiencing body shame, dieting and long-term weight gain.
And the younger we start this, the better. Dieting in adolescents predicts later onset of obesity (Smolak & Thompson, 2001). With weight concern identified in up to 21% of five-year-old girls, we are faced with a very real social problem that has very real consequences for the lives and health of many thousands of women.
Prevention is better than cure. I believe it is essential to teach women about the risks of dieting and show them that there is another way.
The Non-Diet Approach
The Non-Diet Approach is an evidence-based system to build a positive relationship with food, improve your health and befriend your body.
As an evidence-based approach, this means;
– It is backed by science and research (ie. Not simply stacked together by a charlatan who wants your money or an extremist who thinks his crazy diet change are a one-size-fits-all solution for humanity).
– You can read studies and information from other objective sources and don’t have to simply take my word for it!
– There is an emphasis on accountability and regulation amongst the registered health care providers who utilise it in patient care.
The Non-Diet Approach is an entire field of dietetic practice and covers everything from mindful eating to positive body image. Here are some core pillars that make up my Non-Diet philosophy:
1. Every human being is worthy of dignity and deserves to feel good about the body they’re in.
2. The focus is on ‘feeling good’, not ‘being good’ or losing weight.
3. When we reconnect with our natural appetite and learn to listen to our bodies, we have everything we need to feel well and energised.
4. Our decisions around food and movement better serve us when they come from a place of self-care and self-love.
5. When we feel good about ourselves, we tend to treat ourselves well.
6. There is no ‘one-size-fits-all’ diet or recipe for wellness, we need to truly listen to our bodies and feel empowered to make choices that serve us as individuals.
7. Your self-worth is separate to what you eat or how much you weigh.
The purpose of My Food Culture (MFC) is to give you the Non-Diet roadmap, tools, systems and strategies to apply these principles and rediscover joyful health.
The Power Of Positive Body Image
Research shows that children discriminate against larger body shapes from the tender young age of three (Kościcka, Czepczor & Brytek-Matera, 2016) and from as young as seven, girls can express dissatisfaction with their body image and know what diets modify their shape. Worse, research shows that thin body idealisation is starting at an increasingly younger age.
Friends, the body image brain washing starts early!
The desire to lose weight – and subsequent dieting behaviours – spells B.A.D.N.E.W.S if we take a bigger picture view of things. Girls who diet during their childhood and adolescence have a paradoxically higher chance of future weight issues (Dulloo & Montani, 2015).
Research also shows that teenagers who misperceive their bodies as being too large are far more likely to diet, fast, pop diet pills or abuse laxatives. In geek-speak terms, ‘body image dissatisfaction is a strong predictor of dieting behaviours’ (Smolak & Thompson, 2001). Ironically and tragically, these unhealthy attempts at weight control are associated with higher weight gain between adolescence and adulthood (Sutin & Terracciano, 2015).
A Final Point: Having A ‘Perfect’ Body Will Not Magically Give You A ‘Perfect’ Life
Ladies, speaking from personal AND professional experience, dieting is not a panacea to all your problems.
I understand. I’ve been there. If you’ve read my personal story, you’ll hopefully know that I totally, wholeheartedly empathise with the sparkling promise of thinness. Once upon a time, it started with me thinking that being thinner would make me a better dancer. This confusion morphed into something far more toxic; when I was thin, I’d be more successful, more lovable, more in control of my life. Somewhere along the line, being thin became synonymous with being happy.
I was in for a big wake up call. I can honestly say, hand over heart, that my ‘thinnest’ time of life was definitely NOT my happiest. After a personal trauma in my early twenties, I lost 10 kilograms in the space of eight weeks, becoming a shadow – metaphorically and physically – of my former self. I was more anxious, lonely and lost than I’d ever felt before. I did not feel beautiful or successful. And during that time, I would have chosen to be a larger size in a heartbeat if it meant being happier. It took a life-shattering event to realise that when you get to the deeper stuff in life, the stuff that really matters, size doesn’t.
So, if you’re holding off on happiness, travel, financial accomplishment, a new career, fulfilling relationships or ‘putting yourself out there’ until you’re a certain size, I urge you to strongly challenge your assumptions about what being thin really means.
Being thin, means you weigh a certain number. That’s it. Thinness doesn’t mean you’re more loveable or worthy of wonderful things. You can start building the life you want right now.
Make no mistake. The combined annual turnover of the European and American dieting industry is somewhere in the vicinity of $150 billion dollars (Dulloo & Montani, 2015). It is not in the interests of Big Business to bust your bubble about dieting. They’re not really selling you a diet. They are selling you a dream. A dream that is doomed to failure by virtue of your DNA, human psychology and the simple fact that looking a certain way isn’t a one-way ticket to getting all you want in life.
With hard work and the right tools, you CAN have all you want in life. And more. I truly believe this in every fibre of my being.
You can feel good – whole, well and health.
You can feel love – for yourself, life and the people around you.
You can radiate confidence and be the very best version of yourself in this lifetime.
However, wasting your energy on harmful diets and body image obsession is not going to make your soul sing and get you there.
Let it go….
Live like a #MFCr and throw all your fucks about body image out the window. Focus on the things that really do bring you closer to health and happiness.
I’ll be damned if I’m not going to have a good time and live like a #MFCr along the way, too.
Dietitians, children, women from all walks of life, are fed the same message that ‘Our bodies aren’t enough. To be beautiful and healthy, we must be thin – and to be thin, we must diet’.
The departure from natural, intuitive eating into the dieting paradigm has not served us well. In my personal and professional experience, diets aren’t making us happy. Diets aren’t making us well. Diets aren’t even making us lose weight for any significant time!
It’s time to spark a new conversation about eating and our bodies, start a newfound culture that works with, not against your body and embrace the truth that health comes in many different shapes and sizes.
May you wake up to the wonder of your beautiful body today!
All my love,
References (APA – 6)
Australian Institute of Health and Welfare. (2018). Overweight and obesity. Retrieved from
Clemons, R. (2017). Is a healthy diet expensive?. Retrieved from
Dulloo, A. G., & Montani, J. P. (2015). Pathways from dieting to weight regain, to obesity and to the metabolic syndrome: An overview. Endocrinology & Metabolism, 16, 1-6. doi: 10.1111/obr.12250
Fred Hutch. (2004). Yo-Yo dieting may have a long-term negative effect on immune function, according to fred hutchinson study. Retrieved from
Kościcka, K., Czepczor, K., & Brytek-Matera, A. (2016). Body size attitudes and body image perception among preschool children and their parents: a preliminary study. Archives of Psychiatry and Psychotherapy, 4, 28-43. doi: 10.12740/APP/65192
Smolak, L., & Thompson, J. K. (2001). Body image, eating disorders, and obesity in youth : Assessment, prevention, and treatment. Washington, DC: Eurospan.
Sutin, A. R., & Terracciano, A. (2015). Body size attitudes and body image perception among preschool children and their parents: A preliminary study. Psychological Science, 26(4), 507- 511. doi: 10.1177/0956797614566319
The Department of Health. (2009). Obesity in australia. Retrieved from
Macpherson-Sànchez, A. E. (2015). Integrating fundamental concepts of obesity and eating disorders: Implications for the obesity epidemic. American Journal of Public Health, 105(4), 71-85. doi: 10.2105/AJPH.2014.302507