“You cannot outrun a bad diet” – is this true?

Listening to a radio discussion on obesity the other day, one commentator flippantly remarked, “Don’t treat your body like a skip,” while everyone agreed on the adage, “You can’t outrun a bad diet.” This phrase is commonly used, but how accurate is it? After reading several academic and news articles (some are in the links below), I have identified the main themes that ran across all of them. Unsurprisingly, social media was divided on this issue, with a wide range of perspectives expressed.

  1. Exercise alone is insufficient for weight loss and health maintenance: While exercise is beneficial for health, it cannot compensate for a poor diet when it comes to weight loss and overall health. Diet plays a critical role in managing weight and preventing diseases, highlighting that no amount of physical activity can fully offset the negative impacts of unhealthy eating habits.
  2. Misconceptions about caloric expenditure and intake: A common theme is the widespread misunderstanding of caloric expenditure and intake. People often overestimate the number of calories burned through exercise and underestimate the calories consumed, which can hinder weight management efforts. This misunderstanding perpetuates the belief that you can eat anything as long as you exercise, a notion all articles debunk.
  3. Holistic approach to health: The articles advocate for a holistic approach to health, which involves both a balanced diet and regular physical activity. They stress that optimal health and longevity cannot be achieved through exercise or diet alone; both are necessary. This holistic view is supported by the synergy between diet and exercise in reducing mortality risks and enhancing overall well-being.
  4. Broader health benefits of exercise: While highlighting the limitations of exercise for weight loss, the articles also discuss its numerous other health benefits. Regular physical activity reduces the risk of various chronic diseases, improves mental health, enhances sleep quality, and boosts overall energy levels. These benefits underscore the importance of maintaining an active lifestyle, regardless of its impact on weight.
  5. Public health implications: The need for balanced public health messages and clinical advice is a recurring theme. Health guidelines should emphasise both dietary improvements and regular physical activity to promote a comprehensive approach to health. Public health strategies must address the obesity crisis by encouraging a combination of mindful eating and increased physical activity.
  6. The principle of energy balance: The concept of energy balance – calories consumed versus calories burned – is central to the discussion. While exercise contributes to this balance, dietary management is equally, if not more, important. Joyner and Phillips (2019), for instance, argue that weight loss paradigms must consider both sides of the energy equation, integrating both diet and exercise for effective weight management.
  7. Synergistic effects of diet and exercise: The articles highlight the synergistic effects of combining a high-quality diet with regular physical activity. Studies cited in the articles show that individuals who adhere to both habits have significantly lower risks of death from all causes, cardiovascular disease, and certain cancers. This synergy underscores the necessity of integrating both lifestyle factors for optimal health outcomes.
  8. Historical and societal changes: The articles reflect on the historical and societal changes contributing to the current obesity crisis. Past lifestyles involved more physically demanding activities, naturally facilitating higher calorie expenditure. In contrast, modern sedentary lifestyles complicate weight management, making dietary vigilance more critical.

The articles collectively emphasise that while exercise is vital for health, it cannot alone mitigate the effects of a poor diet. A balanced approach that includes both mindful eating and regular physical activity is essential for achieving and maintaining good health, reducing mortality risk, and addressing the obesity crisis.

While diet and exercise are critical components of weight loss, they are not the only factors. Several other elements influence weight management, and focusing solely on diet and exercise can be limiting and potentially problematic. Other factors such as genetics, metabolism, sleep, stress, medical conditions, psychological factors, and obesogenic environments also play significant roles. Addressing these additional factors can enhance weight loss efforts and promote overall health and well-being.


Phillips, S.M. and Joyner, M.J., 2019. Out-running ‘bad’ diets: beyond weight loss there is clear evidence of the benefits of physical activity. British Journal of Sports Medicine, 53, pp.854-855.

Ding, D., Van Buskirk, J., Nguyen, B., Stamatakis, E., Elbarbary, M., Veronese, N., Clare, P.J., Lee, M., Ekelund, U. and Fontana, L., 2022. Physical activity, diet quality and all-cause cardiovascular disease and cancer mortality: a prospective study of 346 627 UK Biobank participants. British Journal of Sports Medicine, 56, pp.1148-1156.

You can’t outrun your fork. But that doesn’t mean exercise can’t help you lose weight or change your diet. (theconversation.com)

‘You can’t outrun a bad diet’: here’s the truth about the health adage (telegraph.co.uk)

Can you outrun a poor diet – The University of Sydney

You can’t outrun a bad diet, authors say | American Heart Association

New study shows exercise can’t reverse all the effects of a bad diet (smh.com.au)


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Dave Lee

Dave Lee

Dave Lee has over 30 years experience in the health and fitness sector and has developed the AllActive course range to help make physical activity more accessible to everyone.

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