- Intermittent fasting occurs when you eat only in a certain time window, such as 10:00 a.m. to 6:00 p.m.
- The benefits of intermittent fasting can include weight loss, improved heart health, and lowered blood pressure.
- The potential risks of intermittent fasting include muscle loss, headaches, and hunger.
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Intermittent fasting has become a popular approach for
, playing on the idea that we did not always have food available 24/7, and that our daily snacking habits feed the steadily increasing obesity epidemic.
Like most diets, research into intermittent fasting is ongoing. But preliminary studies, both in humans and animals, show promise for several benefits that go beyond simple weight loss.
“Research continues and so far intermittent fasting has been shown to reduce inflammation, improve insulin sensitivity, [and] lead to an improvement in blood sugar, blood pressure and cholesterol, which can prevent the progression of chronic diseases â, explains VÃ©ronique Contreras, DO, an emergency doctor with AltaMed Health Services.
Here are nine benefits of intermittent fasting, important risks and side effects to consider, plus tips for getting started.
Numerous studies have found that intermittent fasting can help people lose weight. For example, a Systematic review 2015 over 40 studies found that on average, study participants lost 7 to 11 pounds over a 10-week period.
However, it is not known whether intermittent fasting is better than basic calorie restriction. For example, a 2017 study found that a group who fasted every other day (by cutting 75% of their calories) did not lose more weight than a control group who simply cut their calories by 25% each day.
Another Study 2021 found similar results that alternate-day fasting did not lead to greater fat loss than a good old-fashioned calorie reduction.
2. Can reduce inflammatory pain
When your body is on an empty stomach, it means your glucose stores are almost empty, which can help reduce pain. inflammation, said Andrew Wang, MD, professor of immunobiology at the Yale School of Medicine.
To understand how, it is important to approach what intermittent fasting does to your body. When you fast for long, prolonged periods of time, your body ends up using up all of its glucose – the main fuel source that keeps you going – and goes into a process called ketosis, where it burns ketones for fuel and energy. in place.
However, more research is needed to determine whether intermittent fasting should be implemented as an effective tool for patients with inflammatory diseases.
3. Can prevent dementia
As we age, our organs are prone to chronic inflammation called “Inflaming”, Wang said.
Chronic inflammation can contribute to cognitive decline and dementia potentially due to the build-up of plaque in the brain. Fasting can help counter this by reducing inflammation, Wang says.
Animal research suggests fasting may slow down Development Alzheimer’s. Although research has not yet been conducted in humans, a 2019 study found that intermittent fasting can slow cognitive decline and improve symptoms of Alzheimer’s disease in mice.
4. Could help stimulate cognitive functioning
The cognitive benefits of fasting are not limited to the elderly. A small study from 2016 tested amateur weightlifters after a 48-hour fast and found that the fast improved “mental flexibility,” which the researchers defined as the participants’ ability to quickly and efficiently switch between tasks.
5. Can regulate blood sugar
Intermittent fasting can also help regulate blood sugar levels, which is important for protecting against diseases associated with glucose intolerance like type 2 diabetes.
Glucose intolerance occurs when your body cannot control the amount of sugar in your blood, which can lead to dangerously high blood sugar.
Blood sugar rises when you eat, so it naturally drops when you fast, Wang says.
This may explain why a small study 2019 men at risk of type 2
found that intermittent fasting helped improve glucose tolerance.
6. Could improve heart health
Although research on this topic is limited, Wang says it’s safe to assume that intermittent fasting improves heart health by reducing inflammation and protecting against diabetes, which are both risk factors for attacks. heart and stroke.
A small study from 2012 tested Muslims with a history of heart disease who fasted intermittently during Ramadan. After their fast ended, there was an improvement in their 10-year coronary heart disease risk score and a reduction in other cardiac risk factors like lipid profile, systolic blood pressure, and weight.
7. Can lower blood pressure
Another cardiovascular benefit of intermittent fasting is that it can lower blood pressure.
However, the study was touted as a proof of concept, and larger studies are needed to better understand the role of intermittent fasting on blood pressure.
8. Could facilitate cell repair
When your body encounters toxins or suffers damage, it repairs its cells through a process called autophagy. During autophagy, your cells break down damaged parts and recycle these materials into new, healthier substances.
Although human research in this area is limited, intermittent fasting has been shown to stimulate autophagy in animals. A 2018 MIT study in mice found that intermittent fasting can make cells more able to regenerate. Contreras says this holds promise for a possible similar response in humans, especially those who use intermittent fasting to eliminate nighttime snacking, which can inhibit autophagy.
âIf you eat late at night, you increase your glucose and insulin levels while you sleep, which doesn’t allow autophagy,â Contreras explains. âIntermittent fasting has been shown to activate these pathways to remove or repair damaged molecules. “
9. May help prevent cancer
Healthy and optimal autophagy can help suppress tumor growth, while deregulated autophagy can contribute to cancer development, according to a 2018 medical paper.
It is therefore not surprising that scientists are studying whether intermittent fasting can help prevent cancer or slow its progression when used with cancer treatments like chemotherapy.
âAlthough research is still ongoing, studies in patients with certain cancers suggest that it may suppress tumor growth and in some cases prevent regression,â Contreras said.
Side effects and risks
In general, intermittent fasting is safe to try if you’re in relatively good health, Contreras says. This is because you are still getting all the nutrients and calories your body needs, just by compressing your intake into fewer hours of the day.
However, intermittent fasting has been linked to muscle loss. Additionally, some people should proceed with caution when it comes to intermittent fasting as they have more nuanced nutritional needs. Contreras says you should speak with your doctor before starting if you are:
- Under 18
- Have struggled with eating disorders in the past
- are over 65
- Have type 2 diabetes
In fact, it’s a good idea for anyone who has never practiced intermittent fasting, as a doctor who is familiar with this approach can help ensure that you are always getting all the nutrients you need to stay healthy.
This doesn’t mean that starting intermittent fasting will be easy, especially at first. Contreras says you may experience the following symptoms when you start fasting:
Although these are usually not a risk to your health, you should contact a doctor or call 911 immediately if you experience any lightheadedness, lightheadedness, or changes in your alertness.
If you are looking to improve your health and perhaps lose weight, intermittent fasting can be an attractive option. However, since research into intermittent fasting is still ongoing, it’s best to speak with a healthcare professional to see if this approach is right for you.
âIf someone is considering intermittent fasting, it really needs to be individualized,â Contreras explains. “They should see a doctor who knows about intermittent fasting.”
The specifics of intermittent fasting will depend on your lifestyle and your doctor’s advice, but it’s important to develop a plan that works for you.
“The method by which you decide to fast must [be one that] you can keep doing it for the long haul, which fits your lifestyle and goals, and where you have the support you need to get there, âContreras explains.