Fasting has a significant impact on our biological systems, from the cellular self-cleaning process of autophagy to the metabolic effects on weight loss and blood sugar regulation.
In this article, we'll explore the role of fasting beyond just weight management, focusing on its potential to promote a longer lifespan, youthfulness, and overall health.
We'll sift through the growing body of fasting and longevity research, separating fact from fiction. From debunking common misconceptions to exploring different fasting methods and the hurdles that may come with them, we'll equip you with the knowledge you need to try fasting confidently and safely and reap its many benefits.
Discover the link between intermittent fasting and longevity.
Intermittent Fasting: The 12 Ways it Fights Against Aging
Fasting involves abstaining from all food for predetermined periods of time. This practice has fascinated human civilizations throughout history, from the spiritual fasting of Ancient Greeks to the religious rituals of Islam, Christianity, and Buddhism.
As an ancient practice with roots in various cultural and religious traditions, fasting has evolved over thousands of years into more than just a ritual observance. In recent decades, fasting has become the subject of intense scientific research, especially in regard to its effects on longevity and weight loss.
It's now known that fasting causes powerful cellular changes in the body, revealing numerous health benefits beyond shedding fat.
These changes include enhanced cellular repair processes, increased production of beneficial hormones like growth hormone, and improved metabolic health, leading to increased longevity, reduced inflammation, and enhanced cognitive function.
How Fasting Works
Fasting and longevity studies have shown that fasting can influence the aging process in significant ways, including:
Fasting-mimicking diets (or FMDs), which involve short periods of low-calorie consumption followed by normal eating, have demonstrated the ability to prolong lifespan and reduce the development of age-related diseases, such as type 2 diabetes, cardiovascular disease, cancer, and neurological disorders (1).
Fasting triggers a number of important metabolic changes, such as increased ketone production and the expression of specific enzymes, including sirtuins (SIRTs), which play a role in cellular metabolism and aging (2).
Fasting also acts as a trigger for autophagy, leading to cell remodeling, rejuvenation, and improved metabolic health (3).
Autophagy is a self-cleaning process that rejuvenates cells, enhances metabolic efficiency, and reduces the risk of insulin resistance. It's regulated by signaling pathways, including mTOR, AMP-activated protein kinase, and SIRTs, which are well-known for their connections to longevity (3).
Fasting-induced autophagy is associated with improved metabolic outcomes (3). Additionally, fasting may activate autophagy in circulating immune cells, such as monocytes and lymphocytes, contributing to their health-promoting effects on chronic inflammation and cell senescence (6).
Additionally, fasting helps regulate blood glucose (sugar) levels, improve insulin sensitivity, and promote metabolic flexibility. After fasting, glucose levels decrease, and insulin sensitivity improves, leading to better glucose control that helps in the battle against hallmarks of aging and related conditions, including increased risk for metabolic syndrome, weight gain, and type 2 diabetes (4).
When we fast, especially for extended periods, our body adapts by utilizing glucose stores and eventually transitioning to burning fat for energy. This often results in weight loss, especially if fasting is practiced regularly and paired with a healthy diet.
Furthermore, fasting influences the levels of hormones and metabolites crucial for glucose regulation, including glucagon, glucose-dependent insulinotropic polypeptide, and glucagon-like peptide 1 (5). This preventive effect of fasting on insulin resistance ensures gradual changes in blood glucose levels, avoiding harmful spikes and promoting healthy longevity.
What Does Fasting Involve?
Fasting can be categorized into two main categories:
With food-focused diets, people partially "fast" by avoiding certain foods, specifically those linked to poor health, such as sugary, processed foods or, in some cases, meat, gluten, or dairy.
Food-focused diets include widely-known eating patterns such as the Mediterranean diet, vegan diets, or the ketogenic diet. These diets revolve around selecting specific foods while reducing or eliminating others to maintain a healthy weight and improve overall health markers.
On the other hand, time-focused diets do not restrict what you eat but rather when you can eat. To follow intermittent fasting, it’s necessary to establish specific time frames for eating and fasting. The time during which you eat is called your "eating window."
There are several variations of intermittent fasting. These variations allow people to choose the intermittent fasting approach that best fits their lifestyle and goals, making fasting more sustainable.
Here's an overview of common intermittent fasting variations:
- 16:8: This method involves having an eight-hour eating window and a 16-hour period of fasting each day. This is one of the most popular and simple ways to fast because it includes an "overnight fast" that is already common and allows for some flexibility each day.
- Other fasting windows: You can choose longer or shorter fasting periods, such as 12 or 14 hours, to better fit your schedule and preferences.
- 5/2 approach: This approach includes five days of regular eating and two days of strict calorie restriction. During the two restrictive eating days, typically, the calorie limit for the day does not exceed 500 or 600 calories. On non-fasting days, you can eat your normal diet in whichever quantities you want, although sticking to healthy choices and practicing portion control is still recommended.
- Whole-day fasting (24 hours): In this method, you fast for a full 24 hours. Someone might choose to do a day-long fast once per week, once per month, or several times per year.
- Extended fasting (2+ days): This includes longer fasting periods of 36, 48, or 72 hours (or sometimes even longer, such as up to one week). While this can be difficult to practice, it's often very effective at slashing calorie intake, stimulating ketosis and fat loss, and improving detoxification. However, long fasts can also pose certain risks, and therefore, this approach isn't suitable for everyone.
Which Type of Fasting Is Most Effective?
Research indicates that 12 to 14 hours or more of fasting each day can be beneficial for regulating blood glucose levels and supporting other markers of health.
While 14 hours of fasting is a good starting point, increasing the duration of your fasts up to about 36 hours can have even more powerful effects on improving insulin sensitivity, shedding fat, and supporting longevity.
For fasting to be effective, keep these two key points in mind:
While a single day of fasting can lead to weight loss, the lost weight may return as soon as you resume your regular eating habits. This fact underscores the importance of consistency for achieving the best results from fasting.
Some studies have indicated that it may take two to four weeks for fasting's beneficial cellular processes to initiate, emphasizing the need to select the fasting method that you can best stick with over an extended period.
To encourage weight loss (if this is one of your goals), avoid indulging in high-calorie junk food, oversized portions, fried items, and excessive treats during your eating window.
Make an effort to eat a nutrient-rich diet that emphasizes whole, unprocessed foods while within your eating window—which will help ensure you're meeting your nutritional needs.
Furthermore, ensure you obtain enough electrolytes and minerals while fasting, as there's a risk of electrolyte depletion due to fasting increasing urination.
To help replenish lost electrolytes and nutrients while fasting, drink plenty of water and consider using nutritional supplements developed specifically for use during periods of calorie restriction, such as our Fasting Tonic, which provides you with essential micronutrients and electrolytes that can be lost while fasting.
How Fasting Targets 12 Hallmarks of Aging
Here's what research has uncovered about fasting's benefits for fighting markers of aging:
1. Reduces DNA Instability
Our DNA actually contains some mistakes; however, studies suggest that fasting can help prevent accumulated mistakes in our DNA.
Though the current data is quite limited, it seems that fasting can protect stem cells from ionization and chemotherapy, which can make these mistakes problematic (7).
2. Halts Telomere Attrition
The ends of chromosomes become shorter with age. It's believed that Intermittent fasting can increase telomerase activity and improve telomere maintenance (8).
3. Prevents Epigenetic Alterations
Various changes in DNA accumulate during a lifetime. Fasting can lead to positive changes in gene expression and signaling pathways, as well as affect DNA methylation and histone modifications.
The epigenetic changes induced by fasting are tissue-specific and may vary according to different developmental stages (9).
4. Protects Against Proteostasis
Fasting has been shown to influence the loss of proteostasis, revealing a reduction in the number of protein aggregates. Fasting helps protect against hypoxia-induced defects in proteostasis at different developmental stages, in various tissues, and in different models of proteins prone to misfolding or aggregation (10).
5. Controls Cell Cycles
Fasting can extend lifespan across different species by upregulating SIRT1 and AMPK or downregulating mTORC1, genes involved in the control of cell cycles (11).
6. Reduces Mitochondrial Dysfunction
Mitochondria are organelles involved in cellular energy processes inside of cells. During fasting, the body generates new mitochondria, leading to an enhanced overall mitochondrial function and improvements in cellular energy.
Furthermore, fasting contributes to a reduction in mitochondrial damage due to oxidative stress, which is a key cause of aging and "wear and tear" on the body. (12).
7. Prevents Cellular Senescence
Senescent cells, also called "zombie cells," are cells with impaired molecular and cellular mechanisms. Fasting can prevent the accumulation of senescent cells in humans and mice, which are cells with impaired molecular and cellular mechanisms. (13).
Furthermore, prolonged fasting has been shown to reduce circulating IGF-1 levels and PKA activity, leading to changes in signal transduction in hematopoietic stem cells that promote stress resistance, self-renewal, and regeneration (14).
8. Decreases Stem Cell Exhaustion
Prolonged fasting has been shown to protect hematopoietic stem cells from depletion and from hemotherapy-induced damage, promoting their self-renewal and regeneration.These effects are mediated by a reduction in PKA activity and IGF1 levels (14).
9. Improves Intercellular Communication
Dietary restriction leads to an improvement in the inflammatory state by suppressing NF-kB signaling and reducing the release of pro-inflammatory cytokines, including IL-6, TNF-α, and IL-1β (11).
10. Disables Macroautophagy
Autophagy declines during age, but fasting can improve autophagy and help the body clean up senescent, old and damaged cells (15).
11. Fights Chronic inflammation
Long-term inflammation in the body can be associated with oxidative stress; however, fasting can reduce inflammatory processes and the activity of associated genes (16).
12. Supports a Healthy Gut Microbiome
Dysbiosis describes an imbalance of microbes living in your gut microbiome. Fasting revamps the gut microbiome, boosting its diversity and promoting the reorganization of bacteria.
Moreover, fasting causes renewal of the mucosa in the gut lining, supporting changes in immune function and helping to decrease inflammation. (17)
How to Start Fasting
First and foremost, if you'd like to start fasting, begin by consulting with your healthcare provider to ensure it's safe for you. This is especially important if you take medications or have an existing health condition.
When starting to fast, it's best to do so slowly to avoid any adverse reactions.
Begin by selecting the optimal fasting window with which you feel comfortable, considering your daytime and nighttime activities.
For example, you might choose to start with a 14-hour fast, such as by avoiding eating from 7 PM to 9 AM the next morning. Remember, the hours overnight when you're sleeping count towards your fast.
Be mindful of the types of foods you consume within your eating window, as well as the quantity of food consumed. Avoid overeating and try to steer clear of junk food. Choose whole foods to make the most of your eating window and daily calorie intake.
Once you get the hang of fasting, gradually extend your fasting window and shorten your eating window if you wish. If you rather not to extend your fasting window, simply listen to your body and do what's comfortable for you. The most important thing is consistency and regularity.
You can try fasting for 16 hours or even 24 hours+, but if you do, exercise caution to prevent potential side effects, such as by drinking lots of water and consuming some electrolytes.
Precautions When Beginning Fasting
After fasting for an extended period, you'll want to be careful about avoiding heavy meals and fatty foods, as your stomach will be sensitive.
Fasting is contraindicated for pregnant women and those who are breastfeeding. It's also not recommended for adults with type 1 diabetes, those receiving insulin, people with eating disorders, and those with certain restrictions due to gastrointestinal disorders and kidney disease.
Consult your doctor about whether fasting is safe for you if you have a health condition, and undergo blood tests if they deem it necessary. Additionally, your doctor can assist you in selecting an appropriate fasting approach and monitor your condition during the diet, especially if you are considering extended fasting methods.
A Safer, Easier, More Most Effective Way to Fast
Although intermittent fasting does not significantly affect nutrient intake, the body still requires support while fasting.
Fasting Tonic™ can make fasting easier and more sustainable by providing nutritional support and aiding in mitigating side effects.
Fasting and caloric restriction often come with the challenges of hunger and irritability; however, Fasting Tonic™ is designed to naturally alleviate hunger without relying on caffeine, chemicals, or other stimulants.
Additionally, Fasting Tonic™ is precisely formulated to counteract nutrient deficiencies by replenishing vital minerals, ensuring a more comfortable fasting experience without common side effects.
Using Fasting Tonic™ during your fasting window will help boost your intake of electrolytes like sodium, potassium, chloride, calcium, and magnesium, which can be depleted when restricting your calorie intake, leading to symptoms such as headaches, muscle cramps, fatigue, and potential blood pressure irregularities (20).
In addition to providing you with electrolytes, our formula is centered around potent glucomannan micro-beadlets, a soluble dietary fiber extracted from the konjac plant root, known for its remarkable ability to promote a feeling of fullness (18).
Glucomannan also slows sugar absorption in the gut, aiding in blood sugar level control. This can contribute to lowered total cholesterol, LDL cholesterol, and triglycerides while modestly increasing HDL cholesterol (19).
While fasting and calorie restriction offer health benefits, they can prompt the body to utilize muscle as a fuel source, causing lean muscle mass to break down. On top of this, after the age of 30, we experience a 1-2% annual loss of muscle mass, increasing the risk of injuries and impacting metabolic health (21).
Fasting Tonic™ is expertly crafted to safeguard your muscles and sustain strength during these practices. Our formula incorporates creatine, a naturally occurring compound that replenishes muscle fuel and enhances muscle mass, even during fasting (22) (23).
Additionally, Fasting Tonic™ contains calcium β-hydroxy-β-methylbutyrate (Ca-HMB), derived from the amino acid leucine. This compound is known to reduce muscle breakdown and support muscle maintenance during fasting, also contributing to recovery and improved performance (24).
Key Takeaways on the Connection Between Fasting and Longevity
There's still much to explore regarding the relationship between fasting, aging, and longevity. However, it’s already obvious that the proper use of fasting is one of the most effective natural methods for combating age-related changes.
While fasting can have beneficial effects on many cellular and tissue processes, it may also cause some discomfort.
If you wish to reap the many benefits of fasting with greater ease, consider adding Fasting Tonic™ to your routine, which was created with the aim of comprehensively supporting your body while fasting and reducing unwanted effects.fasting, aging, and longevity. However, it’s already obvious that the proper use of fasting is one of the most effective natural methods for combating age-related changes.
While fasting can have beneficial effects on many cellular and tissue processes, it may also cause some discomfort.
If you wish to reap the many benefits of fasting with greater ease, consider adding Fasting Tonic™ to your routine, which was created with the aim of comprehensively supporting your body while fasting and reducing unwanted effects.
