There's a long-held belief that when it comes to overall health and weight management, the impact of food is 80 percent and the impact of exercise is 20 percent. But research suggests exercise could have a surprisingly powerful psychological influence.
Researchers have found that people naturally begin making healthier nutrition choices when they start a regular exercise routine. And as little as three 30-minute workouts a week can spark the change.
All it took was four months of regular exercise for the study participants to naturally shift from a diet of unhealthy foods. Despite being specifically told not to alter their diets, they began craving healthy foods such as lean meats, fresh fruits and vegetables.
"This shows the psychological power of exercise," says Bryce Hastings, Les Mills Head of Research. "When people start working out, it helps them feel healthy, and then they naturally gravitate to healthier behaviors like eating better.”
Hastings adds that when it comes to maintaining a healthy weight, it’s not just the exercise-induced healthier eating that helps. Regular workouts burn fat and build muscle, helping maintain weight loss in the long term. Plus, regular exercise improves everything from mental health and longevity to bone and heart health, plus a wealth of other life-changing improvements.
Why exercise beats strict dieting
Niki Bezzant, a New Zealand-based health and nutrition writer, says there is plenty of evidence that strict diets just don’t work. “Most of us know it, and science has shown it time and again: most people who go on a diet to lose weight will eventually gain back the weight lost, and very likely more.”
“Yes, if you diet, you can lose weight. But we also know that the only way we can keep weight off is by sticking to that diet for life. As anyone who's ever been on a diet knows, that is next to impossible.”
Bezzant explains that restrictive eating can also mess with our heads. “It changes our relationship with food from being simple – about hunger, satisfaction and pleasure – to complex – about deprivation, denial and self-judgment. For some people, that can mean a descent into disordered eating.” With this in mind, dietitians and registered nutritionists are increasingly following a ‘no diet’ approach; refusing to even weigh people who come to them for treatment, in favor of focusing on other benefits that people may gain from body acceptance and eating for health.
A sustainable approach to health
Diet success all comes down to what is sustainable for the long term. So when we make changes to the way we eat, it's important to consider whether the change – giving up carbs, cutting out dairy, or any other restrictive 'rule' – is something we can keep up for the rest of our lives. If the answer is no, we might be better off reconsidering.
Nutrition expert Dr David Katz, founding Director of Yale University’s Yale-Griffin Prevention Research Center, says we need to make a fundamental shift so that we treat a healthy diet in the same way we do exercise.
“We don’t ‘go’ on exercise; we exercise, and generally with the hope of getting fitter, and keeping at it.”
Success is in the long term. And this all comes down to healthy habits.
Need some help? Check out this science-backed habit-building advice.
Key takeaways: Healthy eating and exercise
- Exercise can influence healthier eating habits: Research shows that starting a regular workout routine can naturally lead to better food choices – even without consciously changing your diet.
- Just three workouts a week can spark change: As little as three 30-minute sessions weekly can shift cravings toward lean proteins, fruits, and vegetables.
- Committing to regular exercise can be smarter than restrictive diets: Diets often fail in the long term. Strict dieting may lead to temporary weight loss, but most people regain the weight – and sometimes more – after stopping.
- Restrictive eating can harm mental health: Dieting can complicate our relationship with food, leading to feelings of deprivation and even disordered eating.
- Sustainability is key: Any dietary change should be something you can maintain for life. If not, it may not be worth pursuing.
- Exercise is a lifelong habit: Unlike diets, which people often ‘go on’ and ‘off’, exercise is typically adopted with long-term goals in mind.
