Is Intermittent Fasting Safe
Some people try intermitting fasting for weight management, and others use the method to address chronic conditions such as irritable bowel syndrome, high cholesterol or arthritis. But intermittent fasting isnt for everyone.
Williams stresses that before you try intermittent fasting , you should check in with your primary care practitioner first. Some people should steer clear of trying intermittent fasting:
- Children and teens under age 18.
- Women who are pregnant or breastfeeding.
- People with diabetes or blood sugar problems.
- Those with a history of eating disorders.
But, Williams says, people not in these categories who can do intermittent fasting safely can continue the regimen indefinitely. It can be a lifestyle change, she says, and one with benefits.
Keep in mind that intermittent fasting may have different effects on different people. Talk to your doctor if you start experiencing unusual anxiety, headaches, nausea or other symptoms after you start intermittent fasting.
To Fast Or Not To Fast
Does When You Eat Matter?
What you eat matters. Many studies have shown that the types of food you eat affect your health. But what about the timing? Scientists are just beginning to understand that when you eat may also make a difference.
Throughout history, people have experienced periods when food was either scarce or completely lacking, says Dr. Valter Longo, an NIH-funded longevity researcher at the University of Southern California. So, they were forced to fast, he says.
But current technologylike refrigeration, transportation, and electric lightinghave made food more readily available.
This has shifted our eating patterns, explains Dr. Vicki Catenacci, a nutrition researcher at the University of Colorado. People now eat, on average, throughout a 14-hour period each day.
Studies suggest that this constant food intake may lead to health problems. Researchers have started looking at whether fasting can have potential benefits for some people.
It Could Help Protect Against Depression
Fasting may have an antidepressant effect, thanks to its ability to make feel-good neurotransmitters like serotonin and endogenous opioids more available to your brain. Fasting and calorie restriction have been shown to relieve negative emotions like tension and anger and boost feelings of euphoria.
A 2008 review found that people with depression who reduced their daily calorie intake by 25 percent experienced fewer depressive symptoms over 6 months, without any apparent negative side effects.
Full disclosure: Experts still have a lot to learn about the relationship between fasting and cancer. But animal studies suggest that periodic fasting might have an anticancer effect, meaning that the practice could play a role in cancer prevention.
The research also seems to suggest that fasting could make cancer treatments like chemotherapy more effective.
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Fasting Can Help You Live Longer
Fasting for periods of 12 hours or longer can trigger what is known as autophagy . Autophagy is a process that we go through on a regular basis as we age, and that is to regenerate and repair.
Its sort of like house cleaning on a cellular level.
Old, dead proteins and other toxins that hang around too long tend to clog up our bodies and reduce daily function. This also speeds up the ageing process and can lead to a whole host of other age-related illnesses, including dementia.
There are a few methods that we can use to trigger this process of cell renewal. One of the most effective is fasting! Fasting lowers your insulin levels which can dramatically increase the autophagy process.
Japanese Scientists Discover New Benefits Of Fasting
A team of researchers from the Okinawa Institute of Science and Technology Graduate University in Japan found that there are more benefits to fasting than just losing weight.
Their study, which saw participants undergo a 58-hour fast, found that the body switches from burning glucose to burning fat for energy during fasting, thus producing ketones, butyrates, acylcarnitine and branched-chain amino acids. The team did not include any obese participant in the study, as obesity is known to change markers during fasting.
The participants had their blood drawn 10, 34 and 58 hours from the start of their fast. Some of the markers peaked at 34 hours, while others had not yet plateaued by the end of the 58-hour fast. All in all, the team was able to identify 44 substances whose levels changed over the fasting period. In past studies, researchers were only able to identify 14.
Among the compounds they identified were two butyrates that were nearly invisible at the 10-hour mark but reached major peaks after 34 and 58 hours of fasting. Butyrates are naturally occurring chemicals that help maintain intestinal homeostasis by protecting the intestinal barrier and mucosal immunity.
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Could We Reap The Benefits Of Fasting Without Fasting
While intermittent fasting may have health risks, nutritionists claim it can be good for us if individuals consult with their doctors before adopting such a diet and adhere to it correctly.
But could there be a way to reap the potential health benefits of fasting without actually having to fast? Dr. Longo believes so.
Earlier this week, Dr. Longo and colleagues from USC published a study in the journal Cell Metabolism revealing how a fasting-mimicking diet triggered immune cell regeneration and extended the lifespan of mice.
What is more, on testing the diet in humans who adhered to it for only 5 days a month for 3 months they found it reduced a number of risk factors associated with aging, cardiovascular disease , diabetes and cancer.
The FMD is low in protein, low in unhealthy fats and high in healthy fats, according to the researchers. It stimulates markers linked to fasting, such as low glucose levels and high levels of ketone bodies, in order to mimic the effects of prolonged fasting.
Dr. Longo and colleagues say their diet could promote immune cell regeneration and longevity associated with fasting without the need for food restriction and the potential adverse effects that come with it.
It may be a while before the FMD receives approval from the US Food and Drug Administration for clinical use. First, the team needs to put the diet through a rigorous testing process.
Bonus 10 Lowers Risk Of Deadly Diseases
Cardiovascular disease and obesity are two diseases in particular that fasting greatly lowers your risk of.
It has already been discussed how fasting can greatly lower the fat on your body. When you have less fat on your body, its almost impossible to be obese. Obesity is being grossly overweight or fat. Fasting prevents you from being grossly overweight if you arent there already. If you are already considered to be obese, fasting will slowly help reduce the amount of fat on your body, but there is much more you need to do to get back to a normal weight.
Being obese can lead to cardiovascular disease.The link between cardiovascular disease and fasting isnt exactly known, but there is definitely a correlation. It may be due to fasting decreasing the amount of bad cholesterol in your system which is linked to heart disease. It may also be because your body might metabolize sugar in a much different way when youre fasting.
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May Increase Your Life Span
There are several reasons that intermittent fasting may positively impact our life span weight loss, decreased blood pressure, and most of the benefits we listed above may all contribute to prolonging our life while also increase our quality of life at the same time.
Intermittent fasting has been found to affect longevity in animal studies, having beneficial effects on life span and markets for health, stress, metabolic response, and age-related diseases .
These findings are hard to confirm in human trials as there are many factors that affect epidemiological studies and many different types of fasting. But at the end of the day, some of the benefits of intermittent fasting may increase our quality of life overall and reduce our risk of developing chronic diseases.
Lower Risk Of Cardiovascular Issues
Per the aforementioned Nutrients study, when insulin levels fall, so does the risk of dangerous cardiovascular events, such as congestive heart failure, which is important for patients with type 2 diabetes because they are two to four times more likely to die from heart disease than adults without diabetes, according to the American Heart Association.
The Nutrients study noted that while there arent human studies to confirm the benefit, observational studies have shown IF may deliver both cardiovascular and metabolic benefits. Lowden suspects that changes to metabolic parameters, such as lower levels of triglycerides and a decrease in blood sugar levels, are the result of losing weight and would be achieved no matter how the weight was lost, whether through IF or a low-carb diet, for example.
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The Potential Benefits Of Intermittent Fasting
Since the body is unable to get its energy from food during fasting, it dips into glucose that is stored in the liver and muscles. This begins around 8 hours after the last meal is consumed.
When the stored glucose has been used up, the body then begins to burn fat as a source of energy, which can result in weight loss.
As well as aiding weight loss, Dr. Razeen Mahroof, of the University of Oxford in the UK, explains that the use of fat for energy can help preserve muscle and reduce cholesterol levels.
A detoxification process also occurs, because any toxins stored in the bodys fat are dissolved and removed from the body, he adds, noting that after a few days of fasting, higher levels of endorphins feel-good hormones are produced in the blood, which can have a positive impact on mental well-being.
As mentioned previously, the study by Dr. Longo and colleagues suggests prolonged fasting may also be effective for regenerating immune cells.
When you starve, the system tries to save energy, and one of the things it can do to save energy is to recycle a lot of the immune cells that are not needed, especially those that may be damaged, Dr. Longo explains.
In their study, published in the journal Cell Stem Cell, the team found that repeated cycles of 2-4 days without food over a 6-month period destroyed the old and damaged immune cells in mice and generated new ones.
Tips For Starting Your First 24
As you begin to plan your first 24-hour fast, there are some important considerations to be aware of. In order for you to see 24-hour fasting benefits, you need to be sure that you are eating the correct foods prior to your fast. First, be sure that the last meal prior to your fast is full of healthy fats. This can include foods such as fish, nuts, avocados, and olive oil.
Foods containing healthy fats will help you feel full for a longer period of time, and will reduce tempting cravings. Second, plan to drink plenty of water during your fast to suppress feelings of hunger. Often times, feeling hungry is actually a sign of thirst. Also, be sure that you are only drinking water during your intermittent fast. Finally, avoid all sources of caffeine during the fasting period. Watch out for supplements that contain caffeine, and do not drink tea or coffee during this time.
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How Can Intermittent Fasting Help Me
Many people who practice intermittent fasting do it in order to lower body weight. Normally, intermittent fasting causes you to consume fewer blowouts. Unless you balance by consuming significantly extra through the other meals, you will essentially consume fewer calories.
Intermittent fasting also ameliorates hormone function, which aids in weight loss. Reduced insulin levels, higher HGH levels, and enhanced norepinephrine levels all aid in the decomposition of fat mass.
Ultimately, fasting for a short period of time raises your body’s metabolism, allowing you to burn far greater calories. In other words, intermittent fasting works on striking both sides of the caloric balance. It enhances your metabolic rate while decreasing the quantity of food you eat .
Further Information On The Benefits Of Fasting
Emotional Benefits of Fasting allow for the release and healing of long-held patterns and beliefs, with little effort on our part. Gain insight into this process.Chronic Degenerative Diseases and Fasting Understand the limitations of conventional medicine and when it is appropriate to pursue alternative therapies — such as fasting.
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May Regulate Blood Sugar Levels
Intermittent fasting may also help regulate blood sugar levels, which is important to protect against diseases associated with glucose intolerance like type 2 diabetes.
Glucose intolerance occurs when your body can’t control how much sugar is in your blood, which can lead to dangerously high blood sugar levels.
Blood sugar increases when you eat, so it naturally falls when you fast, Wang says.
That may explain why a small 2019 study of men at risk for type 2 diabetes found that intermittent fasting helped improve glucose tolerance.
Important: If you have diabetes, consult a doctor before fasting, as it can increase the risk of diabetic ketoacidosis for those who use insulin or other medications to treat their diabetes.
What Are The Health Benefits Of Fasting
Fasting is defined as a period of partial or total restriction from all foods or selected foods. Fasting may be done as a part of dieting for weight loss or religious reasons. Given that fasting is a potential remedy for longevity, it has been the subject of many studies. The American Heart Association has stated that regular fasting is associated with lower rates of heart failure and improved metabolism. Thus, fasting could be the key to a long, healthy life. Many studies show that those who fast routinely have an almost 45 percent lower mortality rate compared to those who dont fast during the follow-up period.
Most studies on fasting have been conducted on individuals who fast for religious reasons. This includes long fasts, such as the Islamic Ramadan, Lent and Daniel fast. It has been suggested that fasting, if done right, can have the following health benefits:
- Improvements in pumping action of the heart
- Lowered levels of LDL or bad cholesterol
- Reduced level of fasting insulin
- Increased insulin sensitivity
- Fasting for a short time can produce ketosis, which accentuates weight loss
- Reduced production of inflammatory substances in the body
- Ketosis during fasting triggers several responses, including decreased inflammation, improved blood sugar regulation and better response to physical stress
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Can Help You Lose Weight And Visceral Fat
Many of those who try intermittent fasting are doing it to lose weight .
Generally speaking, intermittent fasting will make you eat fewer meals.
Unless you compensate by eating much more during the other meals, youll end up taking in fewer calories.
Additionally, intermittent fasting enhances hormone function to facilitate weight loss.
Lower insulin levels, higher HGH levels, and increased amounts of norepinephrine all increase the breakdown of body fat and facilitate its use for energy.
For this reason, short-term fasting actually increases your metabolic rate, helping you burn even more calories .
In other words, intermittent fasting works on both sides of the calorie equation. It boosts your metabolic rate and reduces the amount of food you eat .
According to a 2014 review of the scientific literature, intermittent fasting can cause weight loss of 38% over 324 weeks. This is a huge amount .
The study participants also lost 47% of their waist circumference over 624 weeks, which indicates that they lost lots of visceral fat. Visceral fat is the harmful fat in the abdominal cavity that causes disease .
One 2011 review also showed that intermittent fasting caused less muscle loss than continuous calorie restriction .
However, a 2020 randomized trial looked at people who followed the 16/8 method. In this diet, you fast for 16 hours a day and have an 8-hour window to eat.
Has Benefits For Your Brain
Whats 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.
Intermittent fasting helps reduce:
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SUMMARY
Intermittent fasting may have important benefits for brain health. It may increase growth of new neurons and protect the brain from damage.
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Fasting Can Reduce Inflammation
Chronic inflammation has now been linked with the vast majority of chronic diseases. 350 million people worldwide suffer from conditions like arthritis and osteoporosis. Inflammation is caused by the release of cells in our bodies called monocytes that are produced through bad eating habits.
Studies have shown that fasting can put monocytes into sleep mode. Monocytes in the fed state, are far more inflammatory than those monocytes in a fasted state.
How Does Intermittent Fasting Work
There are several different ways to do intermittent fasting, but they are all based on choosing regular time periods to eat and fast. For instance, you might try eating only during an eight-hour period each day and fast for the remainder. Or you might choose to eat only one meal a day two days a week. There are many different intermittent fasting schedules.
Mattson says that after hours without food, the body exhausts its sugar stores and starts burning fat. He refers to this as metabolic switching.
Intermittent fasting contrasts with the normal eating pattern for most Americans, who eat throughout their waking hours, Mattson says. If someone is eating three meals a day, plus snacks, and theyre not exercising, then every time they eat, theyre running on those calories and not burning their fat stores.
Intermittent fasting works by prolonging the period when your body has burned through the calories consumed during your last meal and begins burning fat.
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