5 Potential Physical Health Benefits of Fasting
Fasting is defined as the absence of foods or caloric drinks for a certain amount of time. Intermittent fasting involves cycling between periods of fasting and eating, allowing our body to rebalance hormones and grow strong and resilient.
As science evolves, so does our understanding of how frequent fasting benefits humans in the long run. Up to date, there’s a number of studies that show the science-backed benefits of fasting, and here are the top five that we thought you might find interesting.
1. Weight Management and Fat Loss
While fasting has a wide range of proven benefits, most of us can agree that the number one reason we start any new diet or lifestyle change is to manage our weight and improve fast loss. While traditional restriction diets prove further unsustainable and disappointing, intermittent fasting provides an alternative approach that can be easier for some people to follow.
There’s two primary reasons fasting promotes the healthy weight:
• We end up eating less food
While fasting, our eating frequency naturally decreases. This is a given, but what causes this reduced consumption? The explanation lies in our hormonal responses. Fasting essentially serves as a form of "metabolic reprogramming," diminishing ghrelin (the hunger hormone), enhancing sensitivity to leptin (the satiety hormone), maintaining stable insulin levels, and promoting the body's fat-burning mode. Consequently, we experience decreased hunger and greater fullness with smaller food portions, resulting in reduced calorie intake.
• We regain metabolic flexibility and energy
In simpler terms, metabolic flexibility refers to our body's remarkable ability to switch between different fuel sources, such as carbohydrates and fats, depending on what's available and what our energy needs are at any given moment. Think of it as having a car that can smoothly transition between running on gasoline and electricity. This metabolic adaptability provides us with more options, ultimately promoting higher fat loss and supporting stable energy levels, while sparing lean mass.
2. Alertness/Brain Health
Many health influencers often suggest eating something every few hours to prevent mental fog and a dip in focus. This suggestion stems from the belief that our brain requires a continuous supply of exogenous carbs to function properly, which prevents many people from experiencing the variety of fasting benefits
The human brain accounts for ~25% of our resting metabolic energy and is highly adaptable. In conditions of constant food availability, our brain primarily utilizes glucose as its main energy source. However, in a food-deprived state, our brain possesses all the necessary enzymes to produce energy from ketone bodies - an alternative form of energy for the body.
Simply said, our brain doesn't require a constant supply of carbs, and how well it functions without food depends on how well we train our body to derive most of the energy from fat - achievable with fasting.
This adaptation promotes further benefits, including:
• increased production of brain-derived neurotrophic factor (BDNF), a protein that interacts with neurons that regulate memory, learning and cognitive function;
• neuronal autophagy - a “self-eating” process in which cells repair themselves and recycle waste material;
• cognitive clarity due to reduced fluctuations in blood sugar levels and improved brain energy utilization.
Stabilized blood glucose/ improved insulin sensitivity
Arguably, there's nothing worse for our physical health than chronically elevated levels of glucose, which is the primary cause of the type 2 diabetes epidemic.
Whether we consume rice, bread, pasta, potatoes, cereal, fruit, or any other carbohydrate, it all eventually gets converted into a simple form of sugar called glucose. While glucose is essential as it serves as fuel and is necessary for our functioning, even too much of a "good" thing can be harmful.
Let's simplify how the body processes carbohydrates:
→ We consume carbohydrates.
→ Our glucose levels rise, prompting our pancreas to release insulin. Insulin acts as a "key," enabling glucose to enter cells from the bloodstream
→ Some of the glucose may be immediately used for activities like intense anaerobic exercise
→ Any excess glucose is either fully or partially converted into glycogen, which is stored in muscles and the liver
→ When muscles and liver cells become full with glycogen, any remaining glucose is converted into body fat. Yes, it's sugar that is stored as body fat, not fat itself
Today, when we eat too many carbohydrates, the pancreas produces insulin as nature intended. But if liver and muscle cells are already filled with glycogen, they stop responding to insulin. The insulin receptors on the surface of these cells gradually decrease in number and lose efficiency, essentially ignoring insulin's "knock" on the door. Now, glucose cannot enter muscle or liver cells, leading to its persistence in the bloodstream. The pancreas, being a diligent soldier, senses the presence of glucose and releases even more insulin, which, in turn, exacerbates insulin resistance in the receptors.
Eventually, the excess glucose is converted into fat, but the insulin receptors are damaged in the process.
How to break this cycle? Lower insulin levels regularly through fasting, reduce the consumption of processed carbohydrates, and deplete glycogen stores through daily exercise.
4. Longevity/Autophagy
Autophagy can be compared to the body's version of a "spring cleaning," where cells consume damaged or malfunctioning components within themselves. This crucial process is facilitated by structures known as autophagosomes. Autophagosomes are small vesicles that traverse through cells, scavenging and digesting these defective parts, ultimately converting them into energy. This energy is then utilized by healthier cells, making them even more robust. Think of it as a "survival of the fittest" scenario, where the strongest cells thrive thanks to the help of the weakest ones.
The equation is simple: more autophagosomes = more cellular recycling = stronger cells = a longer life. This process becomes particularly crucial as we age since our cells lose the ability to multiply, and it becomes paramount to ensure that the surviving cells are as resilient as possible.
One of the most straightforward methods to enhance autophagy is through fasting. Fasting not only stimulates autophagy but also boosts the levels of NAD+ and SIRT1, both of which confer anti-aging benefits.
Reduced Chronic Inflammation
Acute inflammation is the body's natural response to injuries or infections. When some “damage” triggers an inflammation, the immune system kicks in, targeting a specific area in the body and beginning the healing process.
Although inflammation has a bad rep, it’s crucial for our survival. However, chronic inflammation is different. Inflammation is typically short and localized. It breaks injured tissue down to then rebuild it back up. But when inflammation is continuous, it can potentially harm not only the damaged tissue, but a healthy one too.
This is the reason why chronic inflammation is linked to conditions like heart disease, cancer, diabetes, arthritis, and autoimmune diseases.
While there are different ways of managing chronic inflammation, fasting is definitely on top of the list.
Fasting:
• Reduces monocytes: a type of white blood cells. When these cells become overactive, they help sustain chronic inflammation. This reduction is often a result of changes in eating habits, especially when we stop consuming excess calories.
Gives rest to the immune system: when we fast, our body shifts its priorities from digesting food and focuses on internal housekeeping and repairs.
• Balances inflammatory markers: it’s suggested fasting helps reduce levels of pro-inflammatory cytokines such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha). At the same time, fasting can increase the production of anti-inflammatory molecules, such as adiponectin.
• Metabolic Improvements: Fasting often leads to improvements in metabolic health, including improved insulin sensitivity and more balanced blood sugar levels. Metabolic dysfunction is closely linked to chronic inflammation, so these improvements help reduce the overall inflammatory burden on the body.
