Key Points

• A recent study shows that high-intensity exercise significantly increases BDNF levels compared to fasting.
• Fasting for 20 hours does not elevate BDNF levels, while even light exercise can boost it.
• Both exercise and fasting have health benefits, but exercise is more effective for activating longevity pathways.

Study Overview

In a study conducted in January 2023, researchers compared the effects of fasting and exercise on circulating levels of BDNF (brain-derived neurotrophic factor). Participants were divided into three groups: one underwent 20 hours of fasting, another performed 90 minutes of light exercise, and the last group engaged in high-intensity exercise for a few minutes.

Key Findings

• Fasting resulted in decreased glucose and increased ketones but did not affect BDNF levels (0:43).
• Light cycling increased serum BDNF by approximately 6-8% (0:76).
• High-intensity exercise led to a 250% increase in BDNF levels, outperforming both fasting and light exercise (1:122).

Autophagy and Exercise

Both fasting and exercise promote autophagy, but exercise activates it more quickly. In humans, it takes at least 16 hours of fasting to see an increase in autophagy, while just 30 minutes of exercise can trigger it (2:254).

Conclusion

The video concludes that while both fasting and exercise are beneficial for health and longevity, exercise is more effective for activating BDNF and autophagy pathways. Regular exercise can provide these benefits more frequently than fasting alone (4:438).

Comment Summary & Sentiment

The comments reflect a mix of agreement and skepticism regarding the study's findings. Many viewers express a preference for exercise over fasting, while others share personal experiences and insights on the topic. Overall, the sentiment is positive, with viewers appreciating the information shared in the video.