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Can a positive mindset truly improve your health—or even help you beat disease? In this episode, Dr. Bobby and guest Sean McDevitt explore the evidence behind optimism, visualization, and prayer to uncover what really works.

In today’s episode of Live Long and Well, Dr. Bobby is joined by fitness and life coach Sean McDevitt to explore whether positive thinking can influence health outcomes. They dive into both anecdotal and clinical evidence, starting with sports psychology and then navigating the science behind mindset and disease. 

The conversation opens with laughter and smiles—literally. Inspired by Norman Cousins’ Anatomy of an Illness, Dr. Bobby references a meta-analysis showing genuine smiling does, in fact, temporarily boost happiness, while artificial smiling (like holding a pen in your mouth) doesn’t.

They begin with sports, where 86 studies show that visualizing athletic success can improve performance in agility, strength, and game-specific skills. Next, they ask a deeper question: does having a positive attitude affect the progression of serious disease? 

A meta-analysis of 26 studies on life satisfaction and longevity suggests happy people may live longer—especially when it comes to heart health. Optimism, for instance, was linked to a 35% reduction in cardiovascular events and a 15% decrease in all-cause mortality.

However, when it comes to cancer, the picture gets murkier. A review of 165 studies links stress to poorer survival, but a separate meta-analysis on coping styles found no consistent impact on recurrence or survival. One influential study on breast cancer patients even found that while helplessness predicted worse outcomes, having a “fighting spirit” made no significant difference (source). As Dr. Bobby notes, it’s important not to burden patients with guilt if they can’t “stay positive.”

The critical question becomes: if you're not naturally optimistic, can you cultivate positivity—and will it help? Encouragingly, several intervention studies suggest it might. One trial showed cardiac markers improved after optimism training, and a meta-analysis of 56 RCTs found a 15% boost in immune function after psychological interventions. A small MS study linked mindfulness to better walking ability, and a large RCT on breast cancer showed a 45% drop in recurrence with stress-reduction and mood-enhancing strategies.

Finally, the episode touches on spirituality. While many find comfort in prayer, evidence from an RCT of 800 ICU patients and a [meta-analysis] shows no significant impac