Summary
This Huberman Lab Podcast episode focuses on the science of tools for fat loss, with a particular emphasis on the role of the nervous system in governing fat loss. The host discusses various tools for fat loss, including cold exposure, brown fat, beige fat, NEAT, and the role of innervation between the nervous system and fat. The episode also covers the importance of sleep, essential fatty acids, glutamine, fermented foods, iodine, and selenium for a strong foundation of health and metabolism. The speaker warns against the use of dangerous weight loss drugs like Dinitrophenol (DNP) and encourages listeners to focus on safe and effective ways to activate the nervous system for fat loss.
The use of subtle movement, such as fidgeting, can greatly increase fat metabolism and fat loss. Cold exposure can also be used to accelerate fat loss, but it must be done correctly. The recommended protocol for cold exposure involves getting into cold water or shower until you start to shiver, getting out for one to three minutes without drying off, and then getting back in for one to three minutes to access the shiver point again. The episode discusses the different types of fat in the body, including white fat, brown fat, and beige fat. Brown fat is rich in mitochondria and has a biochemical cascade that allows it to convert food energy into energy within the cells. Cold exposure can trigger activation of brown fat and convert beige fat into true brown fat, leading to increased metabolism and fat burning.
The episode also discusses the relationship between exercise intensity, fasting, and fat burning. Three types of exercise are defined: Sprint Interval Training (SIT), High-Intensity Interval Training (HIIT), and Moderate-Intensity Continuous Training (MICT). The studies show that whether or not you eat before training does not matter for short periods of training, but after 90 minutes of moderate-intensity exercise, eating before the exercise reduces the amount of fat burned. However, if you perform high-intensity training for 20-60 minutes, followed by MICT, you will burn more body fat if you go into the training fasted.
The host explains that while calories burned during exercise are important, the more crucial factor is how much an exercise increases metabolism after the workout. High-intensity exercises, such as weight training or sprints, burn more glycogen during the activity but lead to a greater percentage of fat being burned after the exercise due to increased post-exercise oxygen consumption. On the other hand, low to moderate intensity exercises, such as running or swimming, burn more body fat per unit time during the exercise but lead to more glycogen being burned afterward. The host suggests that a combination of high-intensity training followed by moderate to low-intensity exercise or daily activity is the best way to continue burning body fat.
The episode also discusses compounds that increase fat oxidation and mobilization, such as caffeine, which can enhance fat burning by increasing epinephrine and adrenaline release. GLP-1 is a compound that increases fat burning and can be triggered by the ingestion of yerba mate. Pharmaceutical drugs such as Semaglutide also increase GLP-1 but should only be used with a prescription. Other compounds that reduce insulin and increase fat oxidation include berberine and metformin. Lowering insulin levels through diet can also increase fat oxidation. L-carnitine and acetyl-L-carnitine can also facilitate fat oxidation and have additional benefits such as improving sperm quality and reducing fatigue during exercise.
