Micro-fasting Health Benefits Research

1. Intermittent Fasting Changes The Function of
Cells, Genes and Hormones
When you don’t eat for a while, several things happen in your body.
For example, your body initiates important cellular repair processes and changes
hormone levels to make stored body fat more accessible.
Here are some of the changes that occur in your body during fasting:
• Insulin levels: Blood levels of insulin drop significantly, which facilitates fat burning (1).
• Human growth hormone: The blood levels of growth hormone may increase as much
as 5-fold (2, 3). Higher levels of this hormone facilitate fat burning and muscle gain, and
have numerous other benefits (4, 5).
• Cellular repair: The body induces important cellular repair processes, such as
removing waste material from cells (6).
• Gene expression: There are beneficial changes in several genes and molecules
related to longevity and protection against disease (7, 8).
Many of the benefits of intermittent fasting are related to these changes in hormones,
gene expression and function of cells.
2. Intermittent Fasting Can Help You Lose Weight
and Belly Fat
Many of those who try intermittent fasting are doing it in order to lose weight (9).
Generally speaking, intermittent fasting will make you eat fewer meals.
Unless if you compensate by eating much more during the other meals, you will end up
taking in fewer calories.
Additionally, intermittent fasting enhances hormone function to facilitate weight loss.
Lower insulin levels, higher growth hormone levels and increased amounts of
norepinephrine (noradrenaline) all increase the breakdown of body fat and facilitate its
use for energy.
For this reason, short-term fasting actually increases your metabolic rate by 3.6-14%,
helping you burn even more calories (10, 11).
In other words, intermittent fasting works on both sides of the calorie equation. It boosts
your metabolic rate (increases calories out) and reduces the amount of food you eat
(reduces calories in).
According to a 2014 review of the scientific literature, intermittent fasting can cause
weight loss of 3-8% over 3-24 weeks (12). This is a huge amount.
The people also lost 4-7% of their waist circumference, which indicates that they lost
lots of belly fat, the harmful fat in the abdominal cavity that causes disease.
One review study also showed that intermittent fasting caused less muscle loss than
continuous calorie restriction (13).
3. Intermittent Fasting Can Reduce Insulin
Resistance, Lowering Your Risk of Type 2
Diabetes
Type 2 diabetes has become incredibly common in recent decades.
Its main feature is high blood sugar levels in the context of insulin resistance.
Anything that reduces insulin resistance should help lower blood sugar levels and
protect against type 2 diabetes.
Interestingly, intermittent fasting has been shown to have major benefits for insulin
resistance and lead to an impressive reduction in blood sugar levels (12).
In human studies on intermittent fasting, fasting blood sugar has been reduced by 3-6%,
while fasting insulin has been reduced by 20-31% (12).
One study in diabetic rats also showed that intermittent fasting protected against kidney
damage, one of the most severe complications of diabetes (13).
What this implies, is that intermittent fasting may be highly protective for people who are
at risk of developing type 2 diabetes.
4. Intermittent Fasting Can Reduce Oxidative
Stress and Inflammation in The Body
Oxidative stress is one of the steps towards aging and many chronic diseases (14).
It involves unstable molecules called free radicals, which react with other important
molecules (like protein and DNA) and damage them (15).
Several studies show that intermittent fasting may enhance the body’s resistance to
oxidative stress (16, 17).
Additionally, studies show that intermittent fasting can help fight inflammation, another
key driver of all sorts of common diseases (17, 18, 19).
5. Intermittent Fasting May be Beneficial For Heart
Health
Heart disease is currently the world’s biggest killer (20).
It is known that various health markers (so-called “risk factors”) are associated with
either an increased or decreased risk of heart disease.
Intermittent fasting has been shown to improve numerous different risk factors, including
blood pressure, total and LDL cholesterol, blood triglycerides, inflammatory markers and
blood sugar levels (12, 21, 22, 23)
However, a lot of this is based on animal studies. The effects on heart health need to be
studied a lot further in humans before recommendations can be made.
6. Intermittent Fasting Induces Various Cellular
Repair Processes
When we fast, the cells in the body initiate a cellular “waste removal” process
called autophagy (7, 24).
This involves the cells breaking down and metabolizing broken and dysfunctional
proteins that build up inside cells over time.
Increased autophagy may provide protection against several diseases, including cancer
and Alzheimer’s disease (25, 26).
7. Intermittent Fasting May Help Prevent Cancer
Cancer is a terrible disease, characterized by uncontrolled growth of cells.
Fasting has been shown to have several beneficial effects on metabolism that may lead
to reduced risk of cancer.
Although human studies are needed, promising evidence from animal studies indicates
that intermittent fasting may help prevent cancer (27, 28, 29, 30).
There is also some evidence on human cancer patients, showing that fasting reduced
various side effects of chemotherapy (31).
8. Intermittent Fasting is Good For Your Brain
What is good for the body is often good for the brain as well.
Intermittent fasting improves various metabolic features known to be important for brain
health.
This includes reduced oxidative stress, reduced inflammation and a reduction in blood
sugar levels and insulin resistance.
Several studies in rats have shown that intermittent fasting may increase the growth of
new nerve cells, which should have benefits for brain function (32, 33).
It also increases levels of a brain hormone called brain-derived neurotrophic factor
(BDNF) (32, 34, 35), a deficiency of which has been implicated in depression and
various other brain problems (36).
Animal studies have also shown that intermittent fasting protects against brain damage
due to strokes (37).
9. Intermittent Fasting May Help Prevent
Alzheimer’s Disease
Alzheimer’s disease is the world’s most common neurodegenerative disease.
There is no cure available for Alzheimer’s, so preventing it from showing up in the first
place is critical.
A study in rats shows that intermittent fasting may delay the onset of Alzheimer’s
disease or reduce its severity (38).
In a series of case reports, a lifestyle intervention that included daily short-term fasts
was able to significantly improve Alzheimer’s symptoms in 9 out of 10 patients (39).
Animal studies also suggest that fasting may protect against other neurodegenerative
diseases, including Parkinson’s and Huntington’s disease (40, 41).
10. Intermittent Fasting May Extend Your
Lifespan, Helping You Live Longer
One of the most exciting applications of intermittent fasting may be its ability to extend
lifespan.
Studies in rats have shown that intermittent fasting extends lifespan in a similar way as
continuous calorie restriction (42, 43).
In some of these studies, the effects were quite dramatic. In one of them, rats that
fasted every other day lived 83% longer than rats who weren’t fasted (44).
Although this is far from being proven in humans, intermittent fasting has become very
popular among the anti-aging crowd.
Given the known benefits for metabolism and all sorts of health markers, it makes sense
that intermittent fasting could help you live a longer and healthier life.
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