Food Freedom Friday Edition 329 - Is Fasting For You?
Intermittent fasting (IF) is one of the most popular health and fitness trends, and rightly so! Numerous studies show how intermittent fasting benefits your health by reducing inflammation, aiding weight loss, boosting brain function, and promoting cellular generation and renewal–at least in the short term .
There are many different IF plans. Each one involves splitting up a day or number of days into times you eat, and don’t eat.
The 16/8 Intermittent Fasting involves skipping breakfast and eating within an 8 hour period, such as 11-7 p.m. Between the eating window, you fast for 16 hours.
Eat-Stop-Eat Intermittent Fasting is a simple intermittent fasting plan where you avoid eating for 24 hours once or twice a week.
Circadian Rhythm Fasting involves eating during the daylight hours when digestion and metabolism are most active, followed by fasting after 7 pm when metabolism naturally slows down.
Brunch Fasting (AKA 12-14 Hour Fast) is a gentle fast that may be healthier for women and people especially sensitive to low blood sugar. This fast entails 12-14 hours of fasting ending with a late breakfast, or brunch.
Benefits of Intermittent Fasting
Supports Fat-Burning and Weight Loss
Intermittent fasting has been shown to benefit weight loss, by increasing fat burning.
When you eat, the carbohydrates in your food get broken down into glucose (blood sugar). When you stop eating and enter a “fasted state”, your body has to look for different sources of energy. The first place it turns is the sugar (glycogen) stored in your muscles and liver but your body has only a small amount of stored glycogen – approximately 1 or 2 days’ worth.
After glycogen, your body begins breaking down stored fat into energy molecules. These molecules called ketones, replace glucose as the main fuel for your cells.
Furthermore, the more you practice IF the more insulin sensitive you become. When insulin is low your body is better at burning fat. Studies show that due to these hormonal changes fasting can increase your metabolic rate by 3.6–14%.
Circadian Rhythm Fasting in particular, has been shown to optimize the time you eat for cell metabolism, further supporting a healthy weight.
Improves Insulin Sensitivity
When you eat carbohydrates, your blood sugar rises. To move that sugar from your blood and into your cells, your body produces the hormone called insulin.
When you eat a chronically high amount of carbohydrates, you are producing chronically high levels of insulin. Eventually, your cells stop responding. This is called insulin resistance.
With insulin resistance, your blood sugar stays toxically high which can, in turn, lead to numerous hormonal and inflammatory diseases and disorders including heart disease, and diabetes.
Intermittent fasting supports your body in effectively utilizing the glucose in your blood, allowing your body to produce less insulin. With less insulin in your blood, your cells become more responsive to it.
Supports Cellular Renewal and Repair
Research has shown that fasting can support your body in breaking down and destroying damaged and abnormal cells, and recycling them for energy. It’s a process called autophagy.
Autophagy has many benefits including cellular repair and regeneration, reductions in abnormal cell growth, and maintenance of healthy tissues.
Increases Stem cell Production
Fasting allows your body to enter a mode of cellular repair. Since stem cells are the primary repair system in your body, when you fast, they increase.
A fasted body reduces energy use by rapidly shrinking organs, tissues, and different cells in your blood, including a dramatic 28% decrease in white blood cells. This lack of blood cells sends the body into repair mode, stimulating stem cell growth.
Studies show that fasting can increase stem cells in the muscles, intestines, and brain while supporting the body’s ability to regenerate stem cells even when not in a fasted state.
Boosts Human Growth Hormone
Fasting for just a twenty-four-hour period has been shown to increase HGH by 1300% in women, and 2000% for men.
This is significant because HGH is essential for building, maintaining, and repairing healthy tissue in the brain, bones, and other organs. It also speeds up injury healing and muscle repair, boosts metabolism, increases muscle mass, and helps burn fat.
Increases BDNF
BDNF (Brain-Derived Neurotrophic Factor) is a naturally occurring growth hormone responsible for the creation of new neurons.
The intermittent fasting benefits of increased BDNF include better moods, improved cognitive ability, higher productivity, and improved memory. BDNF can also reduce the risks of neurodegenerative diseases like dementia, Alzheimer’s, and Parkinson’s.
Reduces Inflammation
Chronic inflammation is the root cause of chronic illness worldwide, and fasting can help.
Fasting can reduce inflammatory activities and reduce chronic inflammation. IF has the ability to improve nearly every marker of physical and mental health while reducing the risk of disease.
Improves Energy and May Improve Longevity
The intermittent fasting benefit of switching your body into using fat by turning them into free fatty acids and ketones can increase your energy levels.
Ketones support a process called mitophagy. Mitophagy is the breaking down of old, damaged, and dysfunctional mitochondria–the energy factories of each cell–and replacing them with new mitochondria.
Researchers point to this process as one of the reasons why in studies, intermittent fasting can extend the lifespan of rats by 36–83%. Though promising, more research needs to be done to confirm similar effects in humans
Fasting also saves your body the energy it would be using for digestion. In studies we see that this extra energy can boost stem cells that regenerate intestinal lining, helping heal leaky gut syndrome.
Supports Mindful Eating
Modern life is plagued with mindless snacking, emotional eating, craving, and binging processed junk food.
Intermittent fasting helps break the habit of relying on food as an emotional crutch.
Studies note that after a fasted period, the type of food you eat is important to maintaining a healthy relationship to food
Intermittent Fasting Cautions
For people who eat processed foods and a diet high in grains and see oils, augmenting your intermittent fasting plan with other dietary changes to make sure you’re properly fueling your body is important. A well-formulated low carbohydrate diet is a great place to begin.
IF Is Not for Everybody
As with any dietary change, it’s important to look at both the pros and the cons of intermittent fasting.
Recent research is showing that the pros of IF may depend on how long you practice it. The outcomes are certainly influenced by the quality and quantity of food you eat while practicing IF.
A few aspects to consider:
Increased Stress Hormones
The most persistent concern about intermittent fasting is the idea of incurring a stress debt, and a cascade of possible negative effects associated with prolonged stress.
Intermittent fasting that entails long periods between meals can put stress on the body due to the fact that 20% of your brain cells require glucose and cannot be fueled by the ketones produced when the fasted body breaks down fatty acids. That said, your body can produce all the glucose it needs from protein in a process called gluconeogenesis.
However, consistently depleted blood sugar triggers the body to release the stress hormones glucagon, human growth hormone, epinephrine, and cortisol.
In the short term, any negative consequences of these stress hormones are likely outweighed by the benefits of IF for gut health, insulin resistance, and reduced inflammation. However, long term, these stress hormones can lead to negative metabolic changes.
Fasting Hyperglycemia
Though short-term intermittent fasting has been shown to increase insulin sensitivity, this may not be true in the long term.
The consistent release of stress hormones puts the body in a state where it anticipates deprivation. In response, the body increases insulin resistance, while at the same time increasing gluconeogenesis (the synthesizing of glucose from protein), leading to a state of elevated blood sugar called “fasting hyperglycemia.
This process is aimed at conserving energy and storing it as fat to endure future deprivation.
Muscle Wasting
Another result of metabolic stress can be muscle wasting.
A study comparing intermittent fasting to a standard diet of 3 meals a day with snacks in between for 12 weeks, revealed that IF dieters lost significantly more lean mass than fat mass compared with no IF participants.
It becomes important to understand, on an individual level, when fasting is not benefiting you or supporting you achieve your goals
Refueling Risks
Fasting induces controlled atrophy and cell death, which can lead to cellular regeneration and renewal. But it’s crucial to feed these growing cells with quality food.
Beware that eating processed foods high in carbs and added sugars at the end of a fast can increase cancerous activities and cause pre-cancerous lesions especially in the liver and intestines.
Who Should Avoid Intermittent Fasting?
Like any diet and lifestyle change, intermittent fasting is not a great fit for everyone.
If you’re pregnant, or breastfeeding, have an eating disorder, or low body weight, it’s best not to practice intermittent fasting.
Even for people with no pre-existing conditions, IF is often a radical change in metabolism. This can have strong effects on mood and energy.
It’s important to be mindful of the changes taking place within you, and seek professional advice if things don’t feel right. There is also emerging evidence that IF may be most beneficial in the short term, and may have some negative effects in the long term.
It should be noted that the benefits of intermittent fasting have been researched mostly in short-term trials. There is emerging evidence that the long-term practice of IF may have some downsides to be aware of. However, anecdotal evidence tells us that there are tens of thousands of people who have been practicing long-term IF with little to no downsides. The key to a safe and effective IF practice is listening to your body.
Finally
When weighing the pros and cons of intermittent fasting, it appears that short-term intermittent fasting is probably a net positive for most people. IF can be a powerful way to develop mindfulness and around eating patterns leading to healthier diet and lifestyle choices.