Dr. Satchin Panda: Intermittent Fasting to Improve Health, Cognition & Longevity | Huberman Lab

Introduction to Huberman Lab Podcast

Overview: This episode of the Huberman Lab Podcast introduces Dr. Sachin Panda, a professor and director of the Regulatory Biology Laboratory at the Salk Institute of Biological Studies. Dr. Panda's laboratory has made numerous important contributions that impact mental health, physical health, and human performance.

Dr. Panda's Research

• Dr. Panda's laboratory has discovered neurons in the eye and brain that regulate our circadian rhythm.

• His laboratory has also made critical discoveries in terms of how our patterns of eating over time impact our biology and health, particularly related to intermittent fasting or time-restricted feeding.

• During the discussion, Dr. Panda explains how restricting your feeding to specific periods within each 24 hour cycle or exploring longer patterns of fasting and eating cycles can impact the health of your liver, gut, and brain, as well as your mood and ability to perform cognitive work.

Sponsors

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Additional Resources

• Dr. Panda has authored several important books on the topic of intermittent fasting and how it can benefit various aspects of health, including The Circadian Code and The Circadian Diabetes Code.

• Links to Dr. Panda's laboratory website and publications are provided in the show note captions.

Intermittent Fasting and Time Restricted Feeding

Overview: This section discusses the definitions of intermittent fasting and time restricted feeding, as well as how to define them. It also covers the history of caloric restriction and how it relates to these two concepts.

Defining Intermittent Fasting and Time Restricted Feeding

• Intermittent fasting is defined as a pattern of eating that involves reducing calorie intake for a period of time. It has been embedded in the history of caloric restriction for over 100 years.

• Time restricted feeding is a type of intermittent fasting where one eats less for one or two days in a week. It is similar to every other day feeding in mice and rats, which has been shown to have similar health benefits as continuous calorie restriction.

• To define intermittent fasting and time restricted feeding, one must consider how regular one is about the start and stop times. It is also important to note that everyone is doing some form of time restricted feeding to some degree or another, as we all go to sleep without eating.

Benefits of Calorie Restriction and Intermittent Fasting

Overview: This section discusses the benefits of calorie restriction and intermittent fasting, as well as how to define time-restricted feeding.

Calorie Restriction and Intermittent Fasting

• Calorie restriction and intermittent fasting have been studied in humans for weight maintenance, reducing signs of aging, and reversing certain aspects of metabolic disease.

• Intermittent fasting involves intentionally reducing calories for at least one or two days in a week or few days in a month.

• Time-restricted feeding (TRF) is an umbrella term for experiments that involve living without food for several hours, typically 8-12 hours.

Defining Time-Restricted Feeding

• TRF is defined as confining all energy intake from solid and liquid food combined within a consistent window of 8 to 12 hours.

• People have done TRF with 4, 6, and even 2 hours, but these are not feasible to maintain for long periods of time.

• It is important that the feeding window begin and end at the same time, with some flexibility.

Circadian Rhythm

• The concept of TRF came from the science of circadian rhythm, which is an internal timetable present in every cell and organ that pre-programs many molecular aspects of the cells.

• Light is the most dominant time giver, and changing our feeding time can tune our liver clock and other parts of the brain.

• Experiments have shown that by changing our feeding time, we can change our internal clock.

Understanding the Effects of Time Zones on Digestion

Overview: This section discusses the effects of time zones on digestion and how to take advantage of anticipatory activity in different systems to get the best out of it.

Effects of Time Zones on Digestion

• Clock takes at least a day to catch up when flying from LA to New York, meaning it will take three days on average for some people to catch up with the New York Times.

• The function of the clock is to anticipate when you're going to wake up, as the blood pressure, heart rate, and breathing all go up.

• Different organs involved in feeding and digestion have clocks, from saliva production to secretion of digestive juices and absorption of nutrients.

• When the time changes by two or three hours, the clock is expecting food to arrive at a different time.

Advantages of Anticipatory Signals

• Having anticipatory signals helps us better assimilate our food, as gastric juices are deployed at the time when we eat.

• Alarm clocks wake us up but our body is not prepared, leading to slippiness after waking up.

• Daylight saving time can lead to heart attacks due to the body not being ready.

• Intestine has a peristaltic function that slows down at night a few hours after our last meal, leading to food hangover if people eat late at night.

Fasted vs. Fed State

Overview: This section discusses the differences between a fasted and fed state, and how to think about them in terms of breaking a fast. It also covers the difficulty of conducting experiments on humans, and how indirect calorimetry can be used to measure oxygen and carbon dioxide levels in mice.

Fasted vs. Fed State

• Plain water and air do not break a fast, but one teaspoon of sugar may transiently break a fast.

• The fasted state is not necessarily determined by blood glucose levels, but rather by molecular signals downstream of a rise in blood glucose.

• Eating a whole pizza after sitting around all day is very different than eating a whole pizza after running a marathon.

Indirect Calorimetry

• Indirect calorimetry measures oxygen and carbon dioxide levels to determine whether the body is consuming glucose or fat as an energy source.

• In mice, the respiratory exchange ratio (RER) goes from 1 to 0.7-0.75 after 12-14 hours of fasting.

• When mice are given food, the RER immediately begins to rise, indicating that a small amount of food has stopped fat burning and cranked up carbohydrate burning.

• Fat burning occurs from body fat stores, not dietary fat.

Caloric Restriction and Time Restricted Feeding

Overview: This section discusses the experiment conducted by Jotakahasi Islam in 2017 that studied the effects of caloric restriction and time restricted feeding on mice. It also covers the benefits of taking probiotics and vitamins, as well as the importance of gut health.

Caloric Restriction

• Rat experiments were done with caloric restriction, where researchers reduced calorie consumption by 20-30%.

• The rats were given a bolus of food at one time, while the ad libitum FED mice had access to food all the time.

Time Restricted Feeding

• The mice or rats would take the reduced food and eat a little bit of lunch and then snack after three hours.

• They would double up all the food within two to three hours, making it similar to an OMAD diet (one meal a day).

• Researchers had to split the food into 8-15 small portions and give them to the mice every two hours.

Benefits of Probiotics and Vitamins

• Probiotics are vital for microbiotic health and Athletic Greens contains a number of adaptogens, vitamins, and minerals to meet foundational nutritional needs.

• Taking probiotics can help communicate with the brain, immune system, and other biological systems to strongly impact immediate and long-term health.

Results of Experiment

• The mice that ate small meals throughout the day and night lived 10% longer than the ad libitum FED mice.

• The mice that never got into super fasting but snacked throughout the day and night also lived 10% longer.

Time Restricted Feeding and Longevity

Overview: This section discusses the potential health benefits of time restricted feeding, as well as the implications for longevity. It also examines the findings of Joe Takas's study on mice, which suggests that restricting caloric intake to a certain window of time can lead to an increase in lifespan.

Caloric Restriction and Longevity

• Time restricted feeding is a convenient way to eat for many people, as it simplifies the process of portion control.

• In humans, it is difficult to determine if a given treatment or experiment is extending life, whereas with mice, there is some sense of when mortality is likely to occur.

• Joe Takas's study found that if a certain number of calories are distributed throughout the 24-hour cycle, the mice will live 10% longer.

• If the same caloric restricted diet is fit into the active cycle of the day (for humans, the daytime), the mice will live 20% longer.

• This suggests that it is not just important to be sub maintenance and calories for sacral longevity, but also when in the 24 hour cycle you eat those calories.

Biomarkers and Longevity

• Joe Takas's study also found that when mice were fed during night time when they're supposed to eat and they're seeing this getting the same number of calories within 12 hours or two hours, then the mice lived 35% longer than the control.

• This suggests that there may be biomarkers related to longevity that have yet to be discovered.

• The study also found that it didn't matter what pattern of eating the mice were on, provided they were sub maintenance calorie intake.

• This mimics the findings of human studies, which suggest that it doesn't really matter whether or not you use caloric restriction or portion control for weight loss.

Caloric Restriction and Time Restricted Eating in Humans

Overview: This section discusses a human study that looked at the effects of caloric restriction and time restricted eating on weight loss. It also examines the implications of this study for humans, as well as the differences between male and female athletes when it comes to relative energy deficit in sports (REDS).

Caloric Restriction and Time Restricted Eating

• The study compared two groups: one that followed a 10-hour eating window and one that followed an 8-hour eating window.

• Both groups ate the same number of calories, but the 8-hour window group had to eat within a shorter period of time.

• The study found that there was no difference in terms of weight loss between the two groups.

Implications for Humans

• While the study suggests that the length of the feeding window may not matter, more research is needed to determine the effects of different eating windows on success and health.

• A similar experiment done in mice showed that even when the mice were allowed to eat within two or twelve hours, there was no difference in longevity.

• However, it is important to note that these experiments were done only in male mice, and that sex should be taken into account when conducting studies.

Relative Energy Deficit in Sports (REDS)

• REDS is a scientific term used to describe the energy deficit experienced by athletes, particularly those who are more active.

• In females, REDS can lead to amenorrhea, or the loss of the menstrual cycle.

• This is a common occurrence among female athletes, but it is not optimal for health and can have adverse effects in the long term.

Impact of Reduced Eating Intervals on HPA Axis

Overview: This section discusses the potential impact of reduced eating intervals on the hypothalamus pituitary gonadal (HPG) axis, as well as the potential for depression, anxiety, and bipolar-like symptoms. It also covers the development of a mouse model to study the effects of reduced eating intervals, and the potential risks associated with reducing eating intervals to two meals or a very short time.

Impact on HPG Axis

• Reduced eating intervals can disrupt the HPG axis, which can lead to women losing their menstrual cycle.

• The HPG axis can also be disrupted upstream at the hypothalamus or pituitary, leading to symptoms such as depression, anxiety, and bipolar-like symptoms.

Potential Risks

• Reducing eating intervals to two meals or a very short time can have adverse side effects that are not yet known.

• For physically active individuals, 12 hours of feeding and 12 hours of fasting may provide benefits, but this has not been studied systematically in humans.

Research Study

• A research study in Europe used a research app to monitor 200 Swiss participants.

• The participants were divided into two groups: one group was given advice to eat within 12 hours, while the other group was given standard Swiss nutrition advice.

• After three and six months, both groups lost the same amount of body weight and improved their health.

• The study also looked at the quality of food consumed by the participants, and found that those who were given advice to eat within 12 hours did not change their nutrition quality.

Conclusion

• The results of the study suggest that Swiss nutritional advice is just as effective as advice to eat within 12 hours for achieving modest weight loss.

• Combining nutrition advice with time restriction may help reduce the time to 10 hours, and could potentially help people avoid RED-S.

• For non-athletes or recreational exercisers, distributing calories across 12 hours may be a good way to maintain weight and avoid RED-S.

Time-Restricted Feeding and Health

Overview: This section discusses the benefits of time-restricted feeding, including its impact on physical exercise, nutrition quality, weight loss, and overall health.

Nutrition Quality

• Eating within 10-12 hours can lead to longer life in mice, according to a study from NIH.

• A recent study published in Cell Reports Medicine explored time-restricted feeding in the context of low carbohydrate and non-low carbohydrate diets.

• The greatest weight loss was achieved with low carbohydrate plus caloric restriction.

Benefits of Time-Restricted Feeding

• Eating some starches can help those who are exercising or working intensely.

• Nutrition quality, quantity, and timing all matter when it comes to maintaining a healthy body weight.

• 40% of people who maintain a healthy body weight are very aware of their diet and nutrition.

• Carbohydrate restriction in conjunction with time-restricted feeding may be the best path for those looking to lose weight.

Other Factors Impacting Health

• Subconscious decisions play a role in maintaining health.

• The pandemic has caused many to take a closer look at their health.

• Starting and stopping eating at more or less the same time each day can have additional benefits.

• These benefits include better sleep, more predictable shifts in alertness and sleepiness, and improved ability to exercise.

• Other timekeepers for our system include light, activity, social connection, and temperature.

Mental Health and Caffeine Intake

Overview: This section discusses the impact of caffeine intake on mental health and gut health. It also provides an interesting history of nighttime activity and the role of coffee in it.

Mental Health

• Caffeine can be a trigger for anxiety and panic attacks, especially when consumed on an empty stomach.

• People with mental health issues should consider breaking their fast before consuming caffeine.

Gut Health

• Caffeine can exacerbate acid reflux and heartburn, especially when consumed on an empty stomach.

• People with acid reflux or heartburn should consider eating something before drinking their first cup of coffee.

History of Nighttime Activity

• Humans have been controlling fire for the last 200,000 years, allowing them to extend their day and engage in activities such as storytelling, dancing, and strategizing.

• Coffee consumption began in the mid-16th century in Istanbul, where people would gather around a communal fire to drink coffee and discuss politics.

Coffee and the Development of Breakfast

Overview: This section discusses the origin of coffee and how it led to the development of breakfast in Turkey. It also explores the idea of using coffee as a stimulant to extend into the night, and the potential gastric distress caused by strong coffee.

Coffee and Prayer

• Coffee was initially used by Muslims to stay awake for their five daily prayers.

• Turkish coffee is particularly thick and intense, and can be difficult to consume.

• Coffee was used to extend into the night, but this could lead to an energetic lag in the afternoon.

Coffee and Breakfast

• To avoid the gastric distress caused by coffee, people began eating something with their coffee, leading to the development of breakfast in Turkey.

• Eating something with coffee allowed people to digest the food before consuming the coffee, thus avoiding acid reflux.

• Coffee actually led to the development of breakfast, not the other way around.

Caffeine Intake

• Caffeine intake should be delayed for a few hours after waking, to allow natural waking up signals to occur.

• In Turkey, the first meal of the day is usually eaten around 8am, and coffee is consumed afterwards.

• Caffeine is like taking a loan out on your energy bank account, with the interest being an energetic lag in the afternoon.

Nighttime Conversation

• A scientist from the University of Washington Seattle traveled to Africa and recorded conversations at night, finding that they were very different from daytime conversations.

• The conversations were not about Tesla's stock, but rather about topics related to their culture.

• This further highlights the importance of understanding cultural context when interpreting conversations.

The Difference Between Morning and Evening Cognition

Overview: This section discusses the differences between morning and evening cognition, as well as the research of Horacio Iglesias on the sleeping patterns of Argentinian Towers.

The Role of Catecholamines

• Catecholamines, such as dopamine, cortisol, and epinephrine, are at much higher levels in the morning than in the evening.

• Horacio Iglesias has done research on the sleeping patterns of Argentinian Towers, who have no access to electricity.

• These Towers consistently go to bed three to three and a half hours after Sunset.

The Role of Fire

• Fire extended the evening, allowing people to stay awake for three to four hours before going to sleep.

• This is why the slip onset variability was very small, with people going to bed within 15 to 30 minutes of one another.

Night Owls vs. Morning People

• Horacio Iglesias has not found evidence of night owls versus morning people in his research.

• This idea has become an ideological identity-related thing, with people trying to protect their identity.

• However, in cultures with fire but no electricity, people go to sleep within 15 minutes of one another.

Personal Experience

• As an undergrad student, the author never went to bed before midnight and took 45 minutes to one hour naps during the day.

• In grad school, he rarely went to bed before 2 am and was very productive during this time.

• After having a baby, he realized he was not a night owl and could go to sleep between 10 and 11 pm.

The Impact of Daylight on Sleep and Circadian Rhythms

Overview: This section discusses the impact of daylight on sleep and circadian rhythms, as well as the implications of this for night owls and early risers. It also looks at the differences between morning and evening discussions, and how social media use should be restricted to a small portion of evening time.

The Impact of Daylight on Sleep and Circadian Rhythms

• A study found that after going camping for a weekend where people awoke with the sunrise and went to bed a few hours after sunset, their melatonin rhythms and cortisol rhythms and sleep-wake rhythms persisted on that schedule for several weeks.

• Even in Horatio's study, he found that almost all the Tobas woke up around sunrise time.

• Louis Potashek and Ingwifu were the first to track one family with familial urban sleep fest syndrome, and they found that there was a mutation in one of the clock genes (PER2) that allowed the clock to run in a way that these people went to bed very early.

Differences Between Morning and Evening Discussions

• Generally, morning discussions are mostly about work and hunting/gathering/farming, while evening discussions are more about expressing oneself and having intellectual freedom.

• For those who work in tech companies and cannot talk about their work, the evening is a time to find freedom and express themselves.

Social Media Use

• Social media use should be restricted to a small portion of evening time, so that people can interact socially within the room in a constructive way or connect with family members.

Night Owls and Light Sensitivity

Overview: This section discusses the potential genetic basis of night owls, as well as the effects of artificial light on circadian rhythms.

Genetic Basis of Night Owls

• Recent studies have looked into the potential genetic basis of night owls.

• It is possible that some people are more sensitive to light than others, meaning that the same level of light in the same household could make some people stay awake late into the night while others are more resistant to light and can go to bed early.

• Artificial light has become increasingly prevalent, and this may be disrupting our circadian clocks.

Effects of Artificial Light

• Artificial light can affect our circadian rhythms by reducing the cortisol-releasing properties of light at night.

• Red light bulbs can help reduce this effect and improve sleep quality.

• This is especially important for teenagers, who tend to be more sensitive to light and stay up late into the night.

Value of Sleep Before Midnight

• There is a common belief that sleep before midnight is more valuable than sleep after midnight.

• This may be due to the fact that bright light in the evening can reduce melatonin levels, making it harder to fall asleep and stay asleep.

• However, the body still needs the same amount of sleep regardless of when it is taken, so it is important to get enough rest.

Definition of Shift Work

Overview: This section provides an overview of the definition of shift work, the percentage of people who are shift workers, and the disproportionate burden of disease that shift workers carry.

Shift Work Definition

• Shift work is defined as staying awake for two or more hours during habitual sleep time (10pm-5am).

• Doing shift work once a week for 50 weeks is enough to disrupt physiology and metabolism.

• Light resets our clock, so when we stay up for two or more hours, our body's clock is trying to catch up for three days.

Percentage of Shift Workers

• According to the US Department of Labor Statistics, one in five working adults is a card carrying shift worker.

• This number increases to 50% when accounting for college students and new mothers.

Burden of Disease

• Shift workers carry a disproportionately heavier burden of age-related diseases such as high blood pressure, high cholesterol, gastrointestinal problems, chronic inflammation, colon cancer, and diabetes.

• Shift workers are often excluded from clinical trials due to the risk that medications may not help them.

Shift Work and Metabolic Dysfunction

Overview: This section discusses the effects of shift work on metabolic health, including how it can lead to pre-diabetic conditions, disruptions in morning blood glucose levels, and the potential for artificial lighting to contribute to obesity.

Shift Work and Sleep Deprivation

• One in five people are true shift workers, while far more people are shift workers by virtue of their late night activities.

• Even dim light in a room while sleeping can lead to disruptions in morning blood glucose levels.

• Reversing these effects is possible, but children with night lights should be aware of the potential risks.

Shift Work and Education

• Half of Americans are shift workers, including high school and college students.

• Horacio Iglesias' study found that college students typically go to bed after midnight.

• Counterintuitively, young people stay up later in the winter months due to artificial lighting.

Shift Work and Diet

• Shift workers may consume more coffee and hot chocolate in the evening, which can delay sleep onset.

• During the COVID pandemic, digital assignment submission deadlines were typically midnight, leading to cramming and late nights.

Shift Work and Obesity

• The US has seen a rapid increase in obesity rates since the early 2000s.

• Late shifted eating and staying up late with artificial lighting could be major factors in the obesity crisis.

• It would be interesting to look at the frequency distribution of assignment submission times to see if late nights are contributing to the obesity crisis.

Time Restricted Eating for Firefighters

Overview: This section discusses the benefits of time restricted eating for firefighters, and how it can help improve their health and reduce their risk of metabolic disease, cancer, and dementia.

Benefits of Time Restricted Eating

• For adults with a day job, the deadline is usually 5 PM. Time restricted eating could be a protocol that harnesses all other protocols, such as exercise, eating, and socializing, while avoiding issues related to disrupted sleep.

• Waking up early and going to bed within three hours of sunset could be the protocol that harnesses all other protocols.

• However, this may be difficult in places like Toronto or Vancouver in wintertime, where people would have to go to bed very early and wake up very early.

• Getting morning sunlight, even through cloud cover, is important no matter where you live in the world.

Conclusion of the Study

• The study was conducted to address the lifestyle of firefighters and shift workers, who are excluded from many studies.

• There are less than 50 studies done to improve the health of shift workers, which is why the study was conducted.

• The major conclusion of the study was that time restricted eating could be beneficial for firefighters, and if they can follow it, everyone else can too.

Eating Within 10 Hours: A Study of Firefighters

Overview: This study looks at the feasibility of firefighters eating within a 10-hour window and the impact it has on their health.

Living the Life of a Firefighter

• Emily Manoogian and Adina Jadurian volunteered to live the life of a firefighter at the busiest fire station in San Diego.

• They reported for duty at 7:30am and were assigned a bed in the station.

• Every time a 911 call came in, they had to run to get into their gear and attend the call.

• On a typical night, they were woken up 10-15 times.

The Study

• 155 firefighters were recruited and assigned to either a Mediterranean diet or a time-restricted eating schedule.

• Those on the time-restricted eating schedule were asked to eat within 10 hours, with the same schedule each day.

• Most of them chose to begin eating between 8am and 11am and finished their last meal 10 hours later.

• Nearly one-third of the firefighters were already healthy with no signs of any illness.

• At the end of the study, there was no significant difference in weight loss or health changes between the two groups.

• However, there was a significant change in the time-restricted eating group's health parameters.

Blood Pressure and Blood Sugar Regulation in Firefighters

Overview: This study looks at the effects of time-restricted eating on blood pressure and blood sugar regulation in firefighters.

Effects on Blood Pressure

• Firefighters who began with high blood pressure saw a significant reduction in systolic and diastolic blood pressure, equivalent to taking an antihypertensive drug.

Effects on Blood Sugar

• Firefighters with high blood sugar were able to better manage their blood glucose levels.

• Shift workers have difficulty managing their blood sugar even when taking medications, due to their work schedule.

Anchor Point for Meal Schedules

• Keeping a regular meal schedule every day (at least 5 out of 7 days) is an anchor point for those who can't reliably control their sleep/wake cycle.

• Staring at screens and multiple middle-of-the-night wakings can lead to blood sugar regulation issues.

Firefighter Study

• Firefighters are woken up by a signal, making them more similar to the standard population.

• Firefighters have the opportunity to sleep after attending calls, and they take advantage of this opportunity.

• The study results suggest that reducing alcohol intake is important for regulating blood sugar.

Alcohol Consumption and Health

Overview: This section discusses the effects of alcohol consumption on health, as well as the importance of philanthropy in funding groundbreaking research.

Alcohol Consumption and Health

• Alcohol consumption can have a negative effect on health, even at three drinks per week.

• Time-restricted feeding is safe for men, women, and children, provided the feeding window is not shorter than eight hours.

• Studies have shown that time-restricted feeding can change the gut microbiome in a way that causes the body to excrete more fat than sugar, leading to increased thermogenesis.

Philanthropy and Research

• Philanthropy is often necessary to fund groundbreaking research, as the NIH is often conservative in its approach to funding.

• The Salk Institute's Innovation Grant Program, funded by Arvind Jacob, allowed for the development of an app that could help people track their food intake.

• 99% of laboratory scientists do not make money off their discoveries, and typically the divide between the institution and the company that puts the discovery to market is slim.

Eating Habits of Adults

Overview: This section discusses the eating habits of adults, including the median number of times people eat per day, the top decile of people who eat 12 times a day, and the likelihood that a person's body will encounter food.

Frequency of Eating

• The median number of times people eat within a 24-hour period is seven.

• 10% of people eat 12 times a day.

• People can eat seven to eight times a day, but the average is 14 hours and 45 minutes.

• 50% of adults are eating within 15 hours or longer.

• Only 10% of adults are eating within the conventional three meals a day.

Snacking Habits

• Snacking has gone up dramatically.

• People who prepare their own dinner are more likely to eat later at night.

• People are eating small snacks throughout the day.

Sleep Habits

• Sleep researchers agree that children and teenagers should sleep between 9-11 hours.

• Young children should sleep 9-10 hours, while teenagers should sleep 8.5-9.5 hours.

• 90% of high school students are chronically sleep deprived.

• Devices and late assignment submission times contribute to this lack of sleep.

• Public health is complicated, but incentivizing people to wake earlier and go to sleep earlier can help.

Meal Timing and Structure

Overview: This section discusses the optimal meal timing and structure for health, as well as the potential benefits of skipping meals or fasting.

Optimal Meal Timing and Structure

• Pediatricians recommend 12 hours between meals as the optimum time frame.

• Skipping one meal per day within a feeding window is an acceptable strategy, as long as the start and end times are not allowed to drift out.

• Moving breakfast or dinner time by 3-4 hours can cause metabolic jet lag in the short term.

Benefits of Fasting

• Fasting has been shown to have health benefits in both mouse studies and human studies.

• Fasting can help with weight loss, but it is important to make sure that macro and micronutrients, vitamins, and electrolytes are still consumed.

• Fasting can also have a positive impact on the brain, potentially helping with treatment-resistant depression.

Long-Term Fasting and Brain Health

Overview: This section discusses the potential benefits of long-term fasting, periodic fasting, and low-calorie diets on brain health. It also examines the potential effects of fat fasting, where people limit their blood glucose by eating mainly healthy fats, such as avocados, olive oils, and nuts.

Fasting and Brain Health

• There is still incoming data on the potential benefits of restricting feeding times and keeping overall blood glucose lower.

• There is too much emphasis now on blood sugar spiking, and it is unclear what the long-term consequences of a very low carbohydrate diet are on the islet cells of the pancreas.

• The liver is a very plastic tissue and tends to react dramatically to lifestyle changes, so it will be interesting to see what happens with long-term ketogenic diets.

• People who work on ketogenic diets often find it difficult to stay in true ketogenic diets due to social pressure or lack of access to food.

• It is unclear what the impact of not engaging the islet cells periodically is.

• People who become bedridden and then exercise again gain back their muscle mass, so it will be interesting to see what happens with people on long-term ketogenic diets.

• Insulin and insulin-like growth factors are involved in muscle protein synthesis, tissue repair, and cognition, so it is important to consider the potential impacts of low carbohydrate diets.

• Metformin and berberine are two drugs that can activate MP kinase and mimic fasting, and rapamycin can reduce mTOR activation.

Metformin and Rapamycin Mimic Fasting State

Overview: This section discusses the potential benefits of taking metformin and rapamycin to mimic the fasting state. It also looks at a study done on mice that showed different effects of metformin depending on the time of day it was taken.

Metformin and Rapamycin

• Metformin and rapamycin both mimic some aspects of the fasting state, leading to potential benefits.

• Many people are taking rapamycin off-label, and there is a long-term metformin study in progress.

Study on Mice

• A study was done on mice measuring their blood glucose at different times of the day.

• The study found that the same dose of metformin had very different effects depending on the time of day it was taken.

• This suggests that taking metformin at the end of the day may trigger the fasting state earlier than the end of digestion, while taking it in the morning may not have the same effect.

Personal Experiences

• The speaker has taken berberine before and experienced two distinct effects.

• Taking berberine with carbohydrates can help flatten out the blood glucose response.

• Taking berberine without carbohydrates can lead to hypoglycemia and a severe headache.

Circadian Effects

• Nuclear hormone receptors have a circadian pattern in gene expression and protein level.

• Metabolism is regulated by circadian rhythms, with fat oxidation being in the opposite phase of feeding.

• Metabolic regulators should also have a circadian rhythm or diurnal cycle to align or misalign with food seeking behavior and eating.

Introduction to Dr. Sachin Panda

Overview: This section introduces Dr. Sachin Panda, a scientist who has done groundbreaking work in circadian biology and time-restricted feeding.

Background:

• Dr. Panda was lucky enough to have an adjunct position at UCSD when his lab was there.

• He has done both animal studies and human studies, with a focus on human health.

• He has written several books, including one related to diabetes and metabolic/blood sugar regulation.

Actionable Knowledge from Dr. Panda

Overview: This section discusses the actionable knowledge that Dr. Panda shared during the podcast.

Actionable Knowledge:

• Dr. Panda discussed dozens of tools and considerations for shift workers and those engaging in shift work.

• He highlighted the relevance of the firefighter study to the general population.

• He provided links to his app, books, and other resources for further learning.

• He discussed the importance of aligning habits to the internal clock.

• He emphasized the need for scientists to take a leadership role in communicating science to the public.

On Time Health App

Overview: This section discusses the On Time Health App, which is designed to help people balance fasting and eating, activity, and sleep.

On Time Health App:

• The app is available in the Apple App Store and distills the science down to five or six timing components.

• It helps people understand the importance of fasting and eating, activity, and sleep.

• It provides users with personalized recommendations based on their lifestyle and goals.

Conclusion

Overview: This section concludes the podcast by thanking Dr. Panda for his time and knowledge.

Conclusion:

• Dr. Panda was thanked for taking the time to discuss these interesting ideas in detail.

• He was thanked for his leadership role in communicating science to the public.

• He was thanked for shining light in the darkness of science.

• The podcast encouraged listeners to subscribe to the YouTube channel and podcast, and leave a review.

Momentous Supplements

Overview: This section discusses the benefits of using Momentous supplements, including their high quality, single ingredient formulations, and international availability. It also provides links to Huberman Lab's social media accounts and website.

Benefits of Momentous Supplements

• Momentous supplements are of the highest quality and used by various sports teams and Department of Defense studies.

• Single ingredient formulations allow for more cost-effective and biologically effective supplement regimens.

• Momentous supplements are available internationally.

Huberman Lab Resources

• Follow Huberman Lab on Instagram, Twitter, Facebook, and Linkedin.

• Subscribe to the Huberman Lab podcast neural network newsletter for free toolkits and summaries of podcast episodes.

• Find PDF examples of previous toolkits at hubermanlab.com.

Conclusion

Overview: This section concludes the discussion with Dr. Sachin Panda and thanks listeners for their interest in science.

Conclusion

• Thank you for joining the conversation with Dr. Sachin Panda.

• Thank you for your interest in science.