Why Diets Don’t Work

Thinking of going on a diet? Research shows that dieting may actually be more harmful than helpful to the body when looking at the long-term impacts.

Unfortunately, diets are marketed with a variety of false promises, incentives and misinformation that leaves consumers feeling frustrated, ripped off and looking for the next ‘quick fix’ to lose weight. Diets such as Keto, Intermittent Fasting (disguised as ‘skipping breakfast’), meal replacement shakes, the Cabbage Soup Diet, Atkins, Fast 800, 5:2 and appetite suppressants, sound appealing – after all, they claim to be backed by evidence and are usually branded to be doctor or dietitian approved.

Many people who follow these diets are successful short term, dropping weight faster than contestants on The Biggest Loser. Dieting is common –1 in 4 Australians currently follow a diet, and over 50% of dieters are following a weight-loss diet.1

However, people find that many of these diets are not suitable for their lifestyle or can be maintained long term, as they create a deprivation mindset, often starve the body and simply leave individuals feeling socially isolated and unhappy. Many people then fall off the bandwagon, with statistics indicating that most people regain the weight they lost, if not more, within 6 years after dieting.2

So, what do people do? They look towards the next ‘quick fix’ to solve their problem and fall back into the diet cycle trap, blaming themselves for another failure. But what if it wasn’t actually the fault of the individual, but the fault of the diet industry?

The Biggest Loser study

Remember The Biggest Loser? A study followed the journeys of 14 contestants and the impact that weight loss had on their metabolisms. Their basal metabolic rate (BMR), weight and caloric requirements were measured at the start of the program, after the show, and at six years. As expected, all of the contestants had a lower BMR after they had lost weight, achieved by following a very low calorie diet (~800kcal).3 However, because their metabolism had slowed down so much and they needed to maintain such a low caloric intake, many of the contestants regained most of the weight they had lost.

What was surprising is that after the contestants regained weight, their BMR was not restored to their pre-weight loss levels.4 Additionally, their leptin levels (fullness hormone) and thyroid hormones were lower than baseline, while their insulin levels had increased.3 This metabolic adaptation that had occurred from rapid weight loss ultimately meant that contestants were unable to maintain their weight loss and compromised their health in the process.

Findings from other studies

Further studies highlight the interesting long-term outcomes of different diets, such as low carbohydrate, intermittent fasting and high protein/fat.2 In general, most diets showed large improvements in biochemical markers, such as blood pressure and cholesterol, after 6 months.2 However, after one year, most biochemical markers had returned to baseline, and participants had also regained weight. The only exception to this was participants who followed a Mediterranean-style diet, as their lipid levels and cholesterol improved and was sustained.2

Is successful weight loss even possible?

Do not worry – all is not lost! They key messages from these studies is that there is no diet that works for everyone. Some people work well with lower carbohydrate diets, while other people don’t. Some people suit intermittent fasting, while others thrive on breakfasts.

Making sustainable dietary changes that you want to follow for life is important in maintaining weight loss and good health.

What has been shown to work is following a Mediterranean-style diet.5 This does not mean eating Italian and Greek food all day every day. A Mediterranean-style diet is one that includes generous amounts of beans, legumes & lentils, fresh fruits and vegetables, lean meats & fish, wholegrains and healthy fats, such as nuts, seeds and olive oil.5

Why is the Waist Busters program different to other weight loss programs?

Here at Waist Busters, we work with individuals to find a dietary pattern that suits them and incorporates the foods that they love. Throughout the Waist Busters program you will receive one-on-one support with one of our dietitians to help you create new habits and step-by-step changes so that you can improve your lifestyle, health and body.

During our 6 month program you will receive evidence-based information, resources, recipes and guidance on how to improve your overall health and maintain a healthy weight for you. Each week your dietitian, who is also a qualified Health Coach, will guide you, keep you accountable to achieve your goals.

Ditch the scales, diet pills and hunger pains.

Click the link below to book a FREE call with one of our Waist Busters team members today!



[1] Australian Bureau of Statistics. (2014). Australian Health Survey: Nutrition First Results – Foods and Nutrients. Retrieved from Australian Bureau of Statistics: https://www.abs.gov.au/statistics/health/health-conditions-and-risks/australian-health-survey-nutrition-first-results-foods-and-nutrients/latest-release#dieting

[2] Ge, L., Sadeghirad, B., Ball, G., da Costa, B. R., Hitchcock, C. L., et al. (2020). Comparison of dietary macronutrient patterns of 14 popular named dietary programmes for weight and cardiovascular risk factor reduction in adults: systematic review and network meta-analysis of randomised trials. BMJ (Clinical research ed.)369, m696. https://doi.org/10.1136/bmj.m696

[3] Fothergill, E., Guo, J., Howard, L., Kerns, J. C., Knuth, N. D., et al. (2016). Persistent metabolic adaptation 6 years after “The Biggest Loser” competition. Obesity (Silver Spring, Md.)24(8), 1612–1619. https://doi.org/10.1002/oby.21538

[4] Anekwe, C. (2022, January 27). Exercise, metabolism, and weight: New research from The Biggest Loser. Retrieved from Harvard Health Publishing: https://www.health.harvard.edu/blog/exercise-metabolism-and-weight-new-research-from-the-biggest-loser-202201272676

[5] Shmerling, R. H. (2020, May 26). When dieting doesn’t work. Retrieved from Harvard Health Publishing : https://www.health.harvard.edu/blog/when-dieting-doesnt-work-2020052519889


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