Water Fasting Scientist: Surprising Link Between Fasting & Cancer! Fasting Completely Resets Your Gut Microbiome!
In this episode of The Diary Of A CEO, Steven Bartlett and Alan Goldhamer explore the science and effects of fasting on the human body. The discussion covers the physiological changes that occur during fasting, including how the body switches from glucose to ketones for fuel, and how this metabolic shift affects brain function and cellular health through processes like autophagy.
Goldhamer shares research findings on fasting's therapeutic applications, particularly for conditions like high blood pressure, PCOS, and gut health issues. The conversation examines different fasting approaches, from daily time-restricted eating to extended water-only fasts, and explains how each method affects the body. The discussion includes specific findings from recent studies, including a 2024 study on how seven-day water fasts impact the gut microbiome.
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1-Page Summary
The Physiological Mechanisms and Effects Of Fasting
During fasting, the body undergoes several significant physiological changes. Within 16-48 hours of fasting, as glycogen stores deplete, the body switches from using glucose to ketones as its primary fuel source. Alan Goldhamer notes that this metabolic shift can positively affect cognitive function compared to the typical glucose fluctuations seen with Western diets.
The increase in ketones, particularly beta-hydroxybutyric acid, triggers increased production of brain-derived neurotrophic factor (BDNF), which helps protect against conditions like Alzheimer's and dementia. Fasting also initiates autophagy, clearing out dysfunctional cells and waste, while regulating electrolytes and fluid balance through a process called natriuresis.
Therapeutic Applications Of Fasting For Treating Health Conditions
According to Goldhamer's research with T. Colin Campbell, fasting shows remarkable effectiveness in treating high blood pressure. In their study of 174 hypertensive patients, participants achieved normal blood pressure without medication through fasting. The benefits extend beyond the fasting period and continue during refeeding.
Fasting has also shown promising results for metabolic and autoimmune conditions. For women with PCOS, Goldhamer reports significant improvements in menstrual cycle regulation and fertility. The practice can also reset the gut microbiome and influence hormonal balance, potentially providing relief for various gastrointestinal and endocrine-related conditions.
Differences Between Fasting Protocols and Their Benefits
Goldhamer discusses various fasting approaches, from intermittent fasting to extended water-only fasts. For weight management, he suggests limiting eating to an 8-12 hour window, noting that many people eat at night out of habit rather than hunger.
While intermittent fasting is more accessible, Goldhamer explains that extended water-only fasts offer greater therapeutic benefits, citing a 2024 study showing significant improvements in gut microbiome after a seven-day water fast. However, he emphasizes that extended fasting requires medical monitoring and structured refeeding protocols to avoid complications and maintain benefits.
1-Page Summary
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Clarifications
- When the body uses ketones as a primary fuel source during fasting, it means that instead of relying on glucose from carbohydrates, it starts breaking down fats to produce ketones for energy. Ketones are molecules produced by the liver from fatty acids during periods of low food intake, like fasting. This metabolic shift can have various effects on the body, including influencing cognitive function and promoting certain health benefits.
- Brain-derived neurotrophic factor (BDNF) is a protein crucial for brain health and function. It promotes the growth, survival, and differentiation of neurons in the brain. Increased levels of BDNF are associated with improved cognitive function, mood regulation, and protection against neurodegenerative diseases like Alzheimer's. Fasting can trigger the production of BDNF, potentially contributing to brain health benefits observed during fasting periods.
- Autophagy is a cellular process that involves the removal of damaged or dysfunctional components within cells. It plays a crucial role in maintaining cellular health by recycling these components to generate energy and building blocks for new cell structures. This process helps cells adapt to stressors and maintain proper function, contributing to overall cell longevity and health. Autophagy is often triggered during fasting or nutrient deprivation to ensure cells can efficiently recycle and renew their components for optimal performance.
- Natriuresis is the process by which the body excretes sodium and water through the urine. During fasting, natriuresis helps regulate electrolyte balance by eliminating excess sodium. This process is essential for maintaining proper fluid balance in the body during periods of restricted food intake. Natriuresis is a natural mechanism that assists in adapting to changes in dietary patterns, such as those experienced during fasting.
- Fasting has shown effectiveness in treating high blood pressure, with research indicating that patients achieved normal blood pressure without medication through fasting. Additionally, fasting has demonstrated positive outcomes for metabolic and autoimmune conditions, such as improving menstrual cycle regulation and fertility in women with PCOS. The practice can also reset the gut microbiome, influence hormonal balance, and potentially provide relief for various gastrointestinal and endocrine-related conditions. Different fasting protocols, from intermittent fasting to extended water-only fasts, offer varying benefits, with extended fasts showing greater therapeutic potential but requiring medical supervision and structured refeeding plans to avoid complications.
- Polycystic ovary syndrome (PCOS) is a common hormonal disorder among women of reproductive age. It can cause irregular periods, excess androgen levels, and polycystic ovaries. Fasting has shown potential benefits for women with PCOS, such as improving menstrual cycle regularity and fertility. The practice may help regulate hormonal imbalances and positively impact metabolic health in individuals with PCOS.
- The gut microbiome consists of trillions of microorganisms living in the digestive tract. Fasting can influence the composition and diversity of these microbes. Research suggests that fasting, especially extended water-only fasts, can positively impact the gut microbiome by promoting beneficial bacteria and reducing harmful ones. This shift in the gut microbiome during fasting may contribute to improved overall health and various therapeutic benefits.
- Refeeding protocols after extended fasting involve a structured approach to reintroducing food gradually to the body. This process helps prevent digestive issues and metabolic complications that can arise from abruptly resuming a regular diet after a prolonged fast. Refeeding typically starts with easily digestible foods like broths and soups before gradually incorporating more complex foods over several days. Monitoring symptoms and adjusting the diet based on individual tolerance is crucial during the refeeding period.
Counterarguments
- While fasting may shift the body to use ketones as a primary fuel source, this may not be sustainable or suitable for everyone, especially those with certain medical conditions or those who are pregnant or breastfeeding.
- The link between increased ketones and the production of BDNF is an area of ongoing research, and the long-term effects of elevated ketone levels on cognitive function and neurological health are not fully understood.
- Autophagy is a complex process, and while fasting may initiate it, the optimal types and durations of fasting to induce autophagy without negative effects are still under investigation.
- The regulation of electrolytes and fluid balance through natriuresis during fasting must be carefully monitored, as it can lead to imbalances and health issues in some individuals.
- The effectiveness of fasting in treating high blood pressure and its comparison to other dietary and lifestyle interventions requires more extensive research to establish long-term efficacy and safety.
- The claim that fasting benefits extend beyond the fasting period and continue during refeeding may not apply universally and depends on individual adherence to healthy dietary patterns post-fasting.
- While fasting shows promising results for metabolic and autoimmune conditions, it is not a one-size-fits-all solution and may not be appropriate for all individuals with these conditions.
- Improvements in menstrual cycle regulation and fertility in women with PCOS through fasting need to be weighed against potential risks and should be considered in the context of comprehensive medical care.
- The impact of fasting on the gut microbiome and hormonal balance is a complex area of study, and the long-term consequences of such changes are not fully understood.
- The suggestion to limit eating to an 8-12 hour window for weight management may not be practical or beneficial for everyone, and individual dietary needs and lifestyles should be considered.
- While extended water-only fasts may offer greater therapeutic benefits, they also come with increased risks, and the evidence supporting their superiority over other forms of fasting is not conclusive.
- The claim of significant improvements in the gut microbiome after a seven-day water fast is based on a single study and should be interpreted with caution until replicated and reviewed by the broader scientific community.
- The requirement for medical monitoring and structured refeeding protocols for extended fasting highlights the potential risks and complexities involved, suggesting that such practices should not be undertaken lightly or without professional guidance.
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The Physiological Mechanisms and Effects Of Fasting
Fasting motivates the body to undergo significant physiological changes, ranging from fuel source alterations to enhanced cellular cleaning mechanisms.
Fasting Switches Fuel Source to Ketones
Glycogen Depletes; Body Metabolizes Fat To Ketones For Brain Fuel Within 16-48 Hours Of Fasting
After about 24 hours of fasting, glycogen stores in muscles and the liver are depleted. At this point, the body must make a choice: to either start metabolizing its fat reserves or break down muscle tissue to produce glucose. To preserve lean tissue, the body adapts by switching the brain’s primary fuel source from glucose to ketones. During the first 16 to 48 hours of fasting, the body undergoes a metabolic shift from burning glucose to metabolizing fat into ketones, particularly beta-hydroxybutyric acid, which becomes the main source of energy for the brain.
Alan Goldhamer discusses the body's adaptability during fasting or a ketogenic diet, indicating that glucose and [restricted term] levels stabilize, which could have a positive effect on cognitive function in contrast to the fluctuations induced by refined carbohydrates typical of a Western diet.
Fasting Boosts Bdnf, Autophagy, and Electrolyte Regulation
Fasting Boosts Bdnf, Protecting the Brain From Oxidative Damage
As the body switches to ketone production, the levels of beta-hydroxybutyric acid in the brain rise, which in turn increases the production of brain-derived neurotrophic factor (BDNF). BDNF plays a significant role in protecting the brain from oxidative damage that can lead to conditions such as Alzheimer's disease and dementia.
Fasting Induces Autophagy, Clearing Senescent Cells and Waste
Fasting initiates autophagy, a process where the body clears out dysfunctional cells, waste, and debris. This cleaning process helps in removing the byproducts of dietary excess and could contribute to increased lifespan. Fasting creates a hormetic effect, ...
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The Physiological Mechanisms and Effects Of Fasting
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Clarifications
- Ketones are molecules produced by the liver when the body is low on glucose. They serve as an alternative energy source, particularly for the brain, during periods of fasting or low carbohydrate intake. Ketones, such as beta-hydroxybutyric acid, can cross the blood-brain barrier and provide fuel for brain function when glucose availability is limited. This metabolic shift to ketones helps preserve muscle mass by sparing protein breakdown for glucose production.
- Glycogen is a form of stored glucose in the body, primarily found in the liver and muscles. When fasting, glycogen stores are depleted within about 24 hours, prompting the body to switch to alternative fuel sources like fat for energy production. This shift helps preserve muscle mass by prioritizing fat breakdown over muscle tissue catabolism.
- A hormetic effect of fasting is when the mild stress of fasting triggers a beneficial response in the body, leading to improved resilience and health. This stress response can activate repair mechanisms and enhance overall well-being. Hormesis suggests that exposure to low levels of stress, like fasting, can have positive effects on cellular health and longevity. Fasting-induced hormesis is a concept where the body's adaptive response to the stress of fasting results in beneficial outcomes.
- Natriuresis is the process where the body excretes excess sodium through urine, helping to regulate sodium levels. This mechanism is important for maintaining fluid balance and preventing issues like hypertension. During fasting, natriuresis can lead t ...
Counterarguments
- While fasting does switch the body's fuel source to ketones, the time frame of 16-48 hours can vary significantly among individuals depending on their metabolic rate, diet, and physical activity levels.
- The depletion of glycogen stores after about 24 hours is a generalization and may not apply to everyone; some people may deplete their glycogen stores more quickly or slowly.
- The shift from glucose to ketone metabolism is not always a smooth transition and can come with side effects such as the "keto flu," which can include fatigue, headaches, and irritability.
- The claim that fasting stabilizes glucose and [restricted term] levels and improves cognitive function is not universally accepted; some studies suggest that cognitive function may be impaired during fasting due to low blood sugar levels.
- While fasting does increase BDNF, the long-term effects of fasting on brain health are not fully understood, and more research is needed to confirm these protective effects.
- The process of autophagy is complex, and while fasting may induce it, the optimal duration and frequency of fasting for autophagy are still under investigation.
- The benefits of autophagy in terms of lifespan extension are largely based on animal studies, and it is not yet clear if these benefits translate to humans.
- Natriuresis during fasting can be beneficial, but excessive loss of sodium and other electrolytes can be dangerous, particularly for individuals with certain health conditions or those taking specific medications.
- Monitoring el ...
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Therapeutic Applications Of Fasting For Treating Health Conditions
Alan Goldhamer and other experts discuss how therapeutic fasting may have a significant impact on various health conditions, including high blood pressure and metabolic and autoimmune diseases.
Fasting May Treat High Blood Pressure, Letting Patients Stop Medication
Goldhamer claims that fasting is the most effective treatment for high blood pressure, a leading cause of death and disability. According to studies he conducted, fasting can normalize blood pressure in hypertensive patients, allowing the majority to cease medication use.
Fasting Normalizes Blood Pressure in Hypertensive Patients
In one study with T. Colin Campbell, 174 consecutive hypertensive patients achieved normal blood pressure without medication through fasting. Goldhamer points out that fasting not only lowers blood pressure during the fasting period but also continues to decrease it further during refeeding.
Fasting Reduces Visceral Fat, [restricted term] Resistance, and Inflammation, Aiding Antihypertensive Effects
Goldhamer emphasizes that fasting helps reduce visceral fat, [restricted term] resistance, and systemic inflammation—all factors contributing to high blood pressure. By addressing these underlying issues, fasting aids in the antihypertensive effects.
Fasting Benefits Metabolic & Autoimmune Conditions Like Type 2 Diabetes & PCOS
Beyond hypertension, fasting has been found to have beneficial impacts on a range of metabolic and autoimmune conditions, implying a potential for fasting to reset gut microbiome and hormonal imbalances.
Fasting Regulates Menstrual Cycles and Fertility in Pcos Women
Fasting has shown particular effectiveness in women with polycystic ovarian syndrome (PCOS), helping to regulate menstrual cycles and improve fertility. It influences the breakdown of [restricted term] hormones, contributing to the treatment of conditions associated with hormonal imbalances.
Goldhamer notes that patients with PCOS have been profoundly affected by water fasting, showing short-term improvements and long-term benefits in their symptoms.
Fasting to Reset Gut Microbiome and Hormones for Gastrointestinal and Endocrine Relief
Fasting can also lead to a reboo ...
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Therapeutic Applications Of Fasting For Treating Health Conditions
Additional Materials
Clarifications
- Fasting can positively influence the gut microbiome by promoting a balance of beneficial bacteria, which is crucial for digestion and immune function. This balance can help regulate hormones related to metabolism and reproductive health. By resetting the gut microbiome through fasting, hormonal imbalances linked to conditions like PCOS can be addressed, potentially improving symptoms and overall health.
- Refeeding after fasting involves gradually reintroducing food to the body to transition it from a fasting state to regular eating. This process is crucial for restoring the balance of beneficial bacteria in the gut microbiome. It helps prevent digestive issues and supports the immune system by promoting a diverse and healthy gut microbiota. Refeeding should be done mindfully and with nutrient-dense foods to optimize the benefits of fasting and maintain gut health.
- Fasting can influence liver function by aiding in the breakdown and elimination of various chemicals, potentially benefiting gastrointestinal and endocrine health. The process of fasting may support the body in clearing out toxins and waste products, which can positively impact the liver's detoxification processes. This detoxification support can contribute to relieving gastrointestinal issues and improving hormonal balance. By giving the digestive system a break and promoting detoxification, fasting may help alleviate symptoms related to gastrointestinal and endocrine conditions.
- Fasti ...
Counterarguments
- While fasting may lower blood pressure in some individuals, it is not universally the most effective treatment; individual responses to fasting can vary, and some patients may respond better to medication or other lifestyle interventions.
- The claim that fasting normalizes blood pressure in hypertensive patients may not account for the complexity of hypertension, which can be influenced by genetic factors, stress, and other health conditions that fasting alone may not address.
- The reduction of visceral fat, [restricted term] resistance, and inflammation through fasting may be beneficial, but long-term sustainability and safety of fasting as a treatment need to be considered, as well as the potential for negative effects such as nutrient deficiencies or disordered eating patterns.
- While fasting may show benefits for metabolic and autoimmune conditions, it is not a cure-all and should be considered as part of a comprehensive treatment plan that includes medical supervision, especially for conditions like type 2 diabetes where blood glucose levels need careful management.
- The regulation of menstrual cycles and fertility in women with PCOS through fasting is an area that requires more research to understand the long-term effects and to ensure that it does not negatively impact bone density or reproductive health.
- The idea that fasting can reset the gut microbiome and hormones suggests a temporary change, but the long-term effect ...
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Differences Between Fasting Protocols and Their Benefits
Fasting is emerging as a popular approach for various health benefits. Alan Goldhamer sheds light on the specifics of different fasting protocols, their benefits, and their practices.
Fasting As a Tool For Caloric and Weight Management
Goldhamer observes the potential for intermittent fasting to aid in weight management and caloric control.
Limiting Eating To an 8-12 Hour Window May Curb Overeating Outside Hunger
According to Goldhamer, by not eating three to four hours before bed and possibly extending the fasting period another four hours in the morning combined with exercise, one can effectively engage in an intermittent fast of up to 16 hours. This can help control hunger and curb overeating. Many people eat at night out of boredom or habit rather than hunger, so sleeping when tired and eating when hungry could minimize overeating.
Intermittent Fasting Is More Accessible Than Supervised Extended Water Fasts
Goldhamer notes that in the study of patients who fasted for an average of about two weeks, followed by a week of refeeding, most participants altered their behavior to maintain weight loss and lower blood pressure. This suggests the benefits of even short-term fasting protocols for health outcomes. Although not directly mentioned, the context implies that Goldhamer considers intermittent fasting a more accessible approach to most people as opposed to medically supervised extended fasts.
Extended Water-Only Fasts Offer Greater Physiological and Therapeutic Benefits Than Intermittent Fasting
Goldhamer delves into the profound physiological changes and health benefits resulting from extended water-only fasting.
Water Fasting Mobilizes Visceral Fat, Toxins, and Improves Biomarkers Like Blood Pressure
Extended water-only fasts have greater therapeutic effects than shorter or modified fasting regimes, according to Goldhamer. He cites a 2024 study which showed a significant shift to a healthier gut microbiome after a seven-day water-only fast. Additionally, fasting mobilizes visceral fat, leading to fat loss but not lean tissue if proper rest is maintained. Patients reported significant visceral fat loss, reducing the need for medication to treat conditions associated with dietary excess.
Water fasting is recognized for its efficiency in addressing important health indicators such as lowering blood pressure quickly. It also has a detoxifying effect on accumulated toxins and is see ...
Here’s what you’ll find in our full summary
Differences Between Fasting Protocols and Their Benefits
Additional Materials
Counterarguments
- Intermittent fasting may not be suitable for everyone, and some individuals may experience negative side effects such as fatigue, irritability, or disordered eating patterns.
- Limiting eating to an 8-12 hour window might not be practical for individuals with certain lifestyles or those who require a more flexible eating schedule, such as shift workers or those with social or family commitments during typical fasting periods.
- The accessibility of intermittent fasting can vary depending on an individual's personal circumstances, health status, and social environment, which can influence their ability to adhere to the fasting protocol.
- While extended water-only fasts may offer greater benefits for some, they may not be necessary or advisable for others, and the risks may outweigh the benefits, especially without proper medical supervision.
- The mobilization of visceral fat and toxins during water fasting is a complex process, and the role of fasting in "detoxification" is not fully supported by scientific evidence, as the body has its own efficient detoxification systems such as the liver and kidneys.
- The improvements in biomarkers like blood pressure from water fasting may not be sustained long-term without accompanying lifestyle changes, ...
Actionables
- You can create a personalized intermittent fasting tracker by using a simple spreadsheet or a whiteboard in your kitchen to log your eating windows and fasting periods. This visual aid will help you stay committed to your fasting schedule and allow you to easily spot patterns or deviations from your plan. For example, mark the start and end of your eating window each day and use color-coding to indicate days when you successfully stick to your plan versus days when you don't.
- Develop a habit of mindful eating by starting a "hunger diary" where you record your physical hunger levels before and after meals during your eating window. Use a scale from 1 to 10 to rate your hunger and fullness, which can help you differentiate between true hunger and emotional or habitual eating. Over time, this practice can enhance your awareness of your body's signals and help you align your eating habits with your actual hunger.
- Engage with a virtual accountability group focused on interm ...
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