Despite its recent surge in
popularity, fasting is a practice that dates back centuries and plays a central
role in many cultures and religions.
Defined as the abstinence from all or some foods or drinks for a
set period, there are many different ways of fasting.
In general, most fasts are performed over 24–72 hours.
On the other hand, intermittent fasting involves cycling between
periods of eating and fasting, ranging from a few hours to a few days at a
time.
Fasting has been shown to have many health benefits, from
increased weight loss to better brain function.
Here are eight health benefits of fasting — backed by science.
1. Promotes Blood Sugar Control by Reducing Insulin Resistance
Several studies have shown fasting to improve blood sugar control,
which could be especially beneficial for people at risk of diabetes.
A study of ten persons with type 2 diabetes found that short-term
intermittent fasting lowered blood sugar levels significantly.
Meanwhile, another review found that intermittent fasting and
alternate-day fasting were as effective as limiting calorie intake to reduce
insulin resistance.
Insulin resistance can be reduced by increasing your body's
sensitivity to insulin, allowing glucose to be delivered more efficiently from
your bloodstream to your cells.
Coupled with the potential blood sugar-lowering effects, this
could help keep your blood sugar steady, preventing spikes and crashes in your
blood sugar levels.
However, keep in mind that fasting may affect blood sugar levels
differently in men and women, according to some research.
For example, a three-week study found that alternate-day fasting
harmed women's blood sugar control while not affecting men.
2. Promotes Better Health by Fighting inflammation
While acute inflammation is a normal immune process used to help
fight off infections, chronic inflammation can have severe consequences for
your health.
According to research, inflammation has been linked to the
development of chronic diseases like heart disease, cancer, and rheumatoid
arthritis.
Certain studies have shown fasting to help reduce inflammation and
promote improved health.
In one study of 50 healthy adults, intermittent fasting for one
month resulted in a significant reduction in inflammatory markers.
Another small study discovered the same effect when people fasted
for 12 hours a day for one month.
One animal study found that following a very low-calorie diet to
mimic the effects of fasting reduced levels of inflammation and was beneficial
in treating multiple sclerosis, a chronic inflammatory condition.
3. May Enhance Heart Health by Improving Blood Pressure,
Triglycerides, and Cholesterol Levels
Heart disease is the leading cause of death globally, responsible
for roughly 31.5 percent of all deaths.
One of the most effective methods to lower your risk of heart
disease is to change your food and lifestyle.
According to several studies, incorporating fasting into your
daily routine may be advantageous to your heart health.
A small study found that fasting on alternate days for eight weeks
reduced levels of "bad" LDL cholesterol and blood triglycerides by
25% and 32%, respectively.
Another study of 110 obese adults found that fasting for three
weeks under medical supervision reduced blood pressure, blood triglycerides,
total cholesterol, and "bad" LDL cholesterol levels.
In addition, research on 4,629 adults found that fasting was
linked to a lower risk of coronary artery disease and diabetes, which is a
crucial risk factor for heart disease.
4. May Boost Brain Function and Prevent Neurodegenerative
Disorders
Several studies have revealed that fasting may have a powerful
effect on brain function, even though most research is limited to animal
studies.
One study in mice showed that practicing intermittent fasting for
11 months improved brain function and structure.
Other animal research has found that fasting can help improve
cognitive function by protecting brain health and increasing nerve cell
generation.
Fasting may benefit the treatment of neurodegenerative illnesses
since it can help reduce inflammation.
According to animal research, fasting may protect against and
improve outcomes for conditions including Alzheimer's disease and Parkinson's
disease.
However, additional research is needed to determine the effects of
fasting on human brain function.
5. Aids Weight Loss by Limiting Calorie Intake and Boosting
metabolism
Many dieters pick up fasting, looking for a quick and easy way to
drop a few pounds.
Theoretically, abstaining from all or certain foods and beverages
should decrease your overall calorie intake, leading to increased weight loss
over time.
Short-term fasting has also been shown to boost metabolism by
boosting levels of the neurotransmitter norepinephrine, which may help with
weight loss.
One review showed that whole-day fasting could reduce body weight
by up to 9% and significantly decrease body fat over 12–24 weeks.
Another study found that intermittent fasting for 3–12 weeks was
just as successful as continuous calorie restriction in weight loss, with body
weight and fat mass dropping by up to 8% and 16%, respectively.
In addition, fasting was more effective than calorie restriction
at increasing fat loss while simultaneously preserving muscle tissue.
6. Increases Growth Hormone Secretion, Which Is Vital for Growth,
Metabolism, Weight Loss, and Muscle Strength
Human growth hormone (HGH) is a protein hormone that is central to
many aspects of your health.
Studies reveal that this vital hormone affects growth, metabolism,
weight loss, and muscle strength.
Several studies have found that fasting could naturally increase
HGH levels.
One study in 11 healthy adults showed that fasting for 24 hours
significantly increased levels of HGH.
Another small study in nine men found that fasting for just two
days led to a 5-fold increase in the HGH production rate.
Fasting may also assist in maintaining stable blood sugar and
insulin levels throughout the day, which may help to optimize HGH levels, as
some evidence suggests that maintaining high insulin levels can lower HGH
levels.
7. Could Delay Aging and Extend the longevity
Several animal studies have found promising results on the
potential lifespan-extending effects of fasting.
In one experiment, rats who fasted every other day had a slower
rate of aging and lived 83 percent longer than rats who did not fast.
Fasting appears to improve longevity and survival rates in
animals, according to other studies.
Current research, however, is still limited to animal studies.
More research is needed to determine how fasting affects human longevity and
aging.
8. May Aid in Cancer Prevention and Increase the Effectiveness of
Chemotherapy
Fasting may help treat and prevent cancer, according to animal and
test-tube research.
One mouse study discovered that fasting on alternate days helped
prevent tumor growth.
Similarly, a test-tube study found that fasting cancer cells for
several cycles were as efficient as chemotherapy at delaying tumor growth and
increasing the effectiveness of chemotherapy drugs against cancer formation.
Unfortunately, most studies focus on the impact of fasting on the
growth of cancer in animals and cells.
Despite these promising findings, additional studies are needed to
look at how fasting may influence human cancer development and treatment.
How to Start Fasting
There are many different types of fasts, making it easy to find a
method that fits your lifestyle.
Here are a few of the most common types of fasting:
Water fasting: Involves drinking only water for a set amount of
Time.
Juice fasting entails drinking just vegetable or fruit juice for a
set amount of time.
Intermittent fasting: Intake is wholly or partially restricted for
a few hours up to a few days at a time, and a regular diet is resumed on other
days.
Partial fasting: Certain foods or drinks such as processed foods,
animal products or caffeine are eliminated from the diet for a set period.
Calorie restriction: Calories are restricted for a few days every
week.
Within these categories are also more specific types of fasts.
For example, intermittent fasting can be broken down into
subcategories, such as alternate-day fasting, which involves eating every other
day, or time-restricted feeding, which entails limiting intake to just a few
hours each day.
To get started, try experimenting with different types of fasting
to find what works best for you.
Safety and Side Effects
Despite the vast list of potential health benefits, fasting may
not suit everyone.
If you have diabetes or have low blood sugar, fasting can cause
severe spikes and falls in your blood sugar levels.
If you have any underlying health conditions or plan to fast for
more than 24 hours, it's essential to consult your doctor first.
Fasting is also not recommended for older adults, adolescents, or
underweight people without medical supervision.
If you decide to try fasting, stay hydrated and eat nutrient-dense
foods during your eating periods to get the most out of the experience.
If fasting for more extended periods, try to minimize intense
physical activity and get plenty of rest.
Final Thoughts
Fasting has been linked to various health benefits, including
weight loss, better blood sugar control, heart health, brain function, and
cancer prevention.
From water fasting to intermittent fasting and calorie
restriction, many different types of fasting fit nearly every lifestyle.
When coupled with a nutritious diet and healthy lifestyle, incorporating fasting into your routine could benefit your health.