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.
What To Do Ifintermittent Fasting Stops Working
In the modern world, its very easy to get what you want immediatelywithout having to work for it. You can just order 10 000 calories to yourdoorstep without leaving the couch, eat it within a few hours, and get all theentertainment you desire. However, some things like your health and fitness requiremore effort and theyre worth working for.
Instead of wanting immediate gratification, realize that consistency and delayed return will make you a better person. Not only will you be more likely to achieve your goals but youll also develop more willpower, self-discipline, and character. This kind of mindset will carry over to other areas of your life as well and youll be more successful in everything else you do.
If you want to start intermittent fasting with resistance training, then check out my Metabolic Autophagy Master Class. Its a 13-hour video course with dozens of videos and a 4-week meal plan/workout routine that tells you exactly what to do and how.
Intermittent Fasting: What Is It And Is It Safe
Intermittent fasting may seem like a recent trend, but actually, humans have periodically refrained from eating for millennia for a host of reasons: Believe it or not, physicians of yesteryear used to prescribe fasting to treat a host of ailments, while ancient philosophers pushed their plates away in attempts to boost their mental clarity. Fasting has also been a form of political protestthink: the hunger strikes of Mahatma Gandhi, Irish Republican prisoners in the 1980s, or British and American suffragettes in the early 1900s.
To this day, avoiding food is a regular part of many religions. Traditionally, Muslims forgo food and beverage during daylight throughout Ramadan; Jews skip eating and drinking on Yom Kippur; and Hindus and Buddhists fast weekly.
Now fasting is trickling into the secular spotlight due to media coverage that claims intermittent fasting not only leads to weight loss and boosts metabolism but that it may also curtail cancer risk and even extend lifespan.;
But is intermittent fasting, a practice thats both ancient and newly trendy, as effective as some attest? Below, we take a closer look.
What is intermittent fasting? The ultimate guide
The theory is that this process may strengthen some cells ability to withstand additional stressors, which explains the potential link between IF and delayed aging as well as a reduced risk of cancer risk. But the benefits have yet to be proven.
Different types of intermittent fasting
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It May Help You Eat Less
Switching to intermittent fasting may naturally help you eat less.
One study found that young men ate 650 fewer calories per day when their food intake was restricted to a four-hour window .
Another study in 24 healthy men and women looked at the effects of a long, 36-hour fast on eating habits. Despite consuming extra calories on the post-fast day, participants dropped their total calorie balance by 1,900 calories, a significant reduction .
Supports Brain Health And Function
Intermittent fasting may help improve memory and mental performance and support brain health/function by protecting neurons in the brain against deterioration and dysfunction .
;emerging evidence suggests that intermittent fasting could be a useful intervention in neurodegenerative diseases such as epilepsy, Alzheimer’s disease, and Parkinson’s disease, and stroke .;;
Keep in mind that it’s not simply the act of fasting alone that may have these potential benefits, decreased inflammation, reductions in body fat, and healthier blood sugar levels have all been linked to healthy brain function.;
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Intermittent Fasting May Not Offer Dramatic Benefits Heres Why
What defines success depends on who you ask.
Intermittent fasting encompasses a few approaches to food: eating during only certain hours of the day, refraining completely on certain days, or drastically reducing calories on a few days of the week. And yet, scientists and practitioners alike insist itâs not a diet. Itâs an eating pattern.
The appeal of intermittent fasting to a general audience is arguably just that: itâs non-dietness. If you limit your eating to certain hours of the day, the reasoning goes, thereâs no need to restrict calories.
It makes sense then that intermittent fasting is often pitted against calorie restriction â specifically reducing calories consumed per day â in scientific studies. The question is: Does it actually help people achieve their health goals, would they be better off trying calorie restriction, or should they choose something else entirely?
Does Intermittent Fasting Have Different Effects On Men And Women
The quick answer is: yes, Intermittent Fasting can affect men and women differently.;
Anecdotally, we have many women in our online coaching program that swear by Intermittent Fasting, while others have had adverse effects.
Lets dig into the science and studies.
A recent PubMed summary concluded thatfasting can be prescribed as a safe medical intervention as well as a lifestyle regimen which can improve womens health in many folds .
Now, in that extract, many of the studies cited are focused on specifically calorie restriction , and they also say that future studies should address this gap by designing medically supervised fasting techniques to extract better evidence.
Digging into the PubMed Archives brought me to the following conclusions :
One small study resulted in the following:;Glucose response to a meal was slightly impaired in women after 3 weeks of treatment, but insulin response was unchanged. Men had no change in glucose response and a significant reduction in insulin response.
Another small study studied the effects on their menstrual cycles after a 72 hour fast which is significantly longer than any fast recommended in this article: in spite of profound metabolic changes, a 72-hour fast during the follicular phase does not affect the menstrual cycle of normal cycling women..
Precision Nutrition a great resource recommends not attempting Intermittent Fasting as a woman if:
- youre pregnant
- you dont sleep well
- youre new to diet and exercise
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Can Promote Disordered Eating
Both Newgent and Dr. Viana point out that intermittent fasting might not promote healthy eating habits, especially for anyone struggling with an eating disorder. Any form of restriction or rulesincluding time-restricted eatingcan exacerbate disordered eating, such as binging during eating windows, says Newgent. It also leads to a preoccupation with food.
May Help Prevent Cancer
Cancer is 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.
Promising evidence from animal studies indicates that intermittent fasting or diets that mimic fasting may help prevent cancer. Research in humans has led to similar findings, although more studies are needed 00224-7″ rel=”nofollow”>26, 27, 28 ).
Theres also some evidence showing that fasting reduced various side effects of chemotherapy in humans 00503-2″ rel=”nofollow”>29, 30).
Intermittent fasting has been shown to help prevent cancer in animal studies and some human studies. Research in humans showed that it can help reduce side effects caused by chemotherapy.
What Is Intermittent Fasting
Many diets focus on what to eat, but intermittent fasting is all about when you eat.
With intermittent fasting, you only eat during a specific time. Fasting for a certain number of hours each day or eating just one meal a couple days a week, can help your body burn fat. And scientific evidence points to some health benefits, as well.
Johns Hopkins neuroscientist , has studied intermittent fasting for 25 years. He says that our bodies have evolved to be able to go without food for many hours, or even several days or longer. In prehistoric times, before humans learned to farm, they were hunters and gatherers who evolved to survive and thrive for long periods without eating. They had to: It took a lot of time and energy to hunt game and gather nuts and berries.
Even 50 years ago, it was easier to maintain a healthy weight. Johns Hopkins dietitian Christie Williams, M.S., R.D.N., explains: There were no computers, and TV shows turned off at 11 p.m.; people stopped eating because they went to bed. Portions were much smaller. More people worked and played outside and, in general, got more exercise.
Nowadays, TV, the internet and other entertainment are available 24/7. We stay awake for longer hours to catch our favorite shows, play games and chat online. Were sitting and snacking all day and most of the night.
Types Of Intermittent Fasting
Intermittent fasting has become very trendy in the past few years, and several different types/methods have emerged.
Here are some of the most popular ones:
- The 16/8 Method: Fast for 16 hours each day, for example by only eating between noon and 8pm.
- Eat-Stop-Eat: Once or twice a week, dont eat anything from dinner one day, until dinner the next day .
- The 5:2 Diet: During 2 days of the week, eat only about 500600 calories.
Then there are many other variations.
There are many different intermittent fasting methods. The most popular ones are the 16/8 method, Eat-Stop-Eat and the 5:2 diet.
What Exactly Is Intermittent Fasting
Intermittent Fasting is nothing more than timing up your food at certain times throughout the day and basically having a window in which you eat. That window can be anywhere between four to eight hours, and you close that window or widen it. You typically put that window in the last third of the day which is when you tend to be more insulin sensitive naturally.
Lets talk about that window for example, instead of eating between 7AM and 8PM, thats a thirteen hour window, were taking that and closing it down maybe to eight, or five, or four hours.
Could Facilitate Cell Repair
When your body encounters toxins or has damage, it repairs its cells through a process called autophagy. During autophagy, your cells break down damaged portions, and recycle those materials into new, healthier substances.;
While human research in this area is limited, intermittent fasting has been shown to boost autophagy in animals. A 2018 MIT study on mice found that intermittent fasting can make cells more adept at regenerating. Contreras says this is promising for a possible similar response in humans, especially those who use intermittent fasting to eliminate late-night snacking, which can inhibit autophagy.;
“If you eat late at night you raise your glucose levels and insulin while you are sleeping, which doesn’t allow autophagy to occur,” Contreras says. “Intermittent fasting has shown to activate these pathways to remove or repair damaged molecules.”
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Youveadapted To The Fast
The body adapts to fasting by becoming more fat-adapted and stimulating certain pathways that promote stress adaptation and energy efficiency. Fasting can indirectly lead to the growth of new mitochondria by activating SIRT1, AMPK, and FOXO3. This increases the bodys energy efficiency, which is great for longevity and energy production, but it can also create mild metabolic adaptation because the body begins to need fewer calories.
It is true that if you do the same kind of intermittent fasting every day,it begins to cause less stress on the body. This is great because youllexperience less of the side effects like hunger and tiredness. However, it canalso create some metabolic adaptation.
To overcome the metabolic adaptation from fasting you have to change thesignal youre sending by either going for a longer fast or going back toeating more often for a while. This will reset your sensitivity to thestimulus.
The caveat is that if you go back to eating 3 or 5 times a day, you mayjust start to subconsciously over-eat calories. Some people also get used tolarger meals with IF and thus have to be more cautious with portion control andsatiety. Thats why I think going back to regular eating isnt the best optionfor most. Instead, you can still do time-restricted eating, just extend youreating window by a few hours first and see what happens. Then, having a 48-hourfast is also great for breaking plateaus.
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.;
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Pros And Cons Of Intermittent Fasting For Women
Some of the benefits of intermittent fasting;may include:
- Sustainable weight loss
- An increase in lean muscle mass
- More energy
- An increase in cell stress response
- A reduction in oxidative stress and inflammation
- Improvement around insulin sensitivity in overweight women
- Increased production of neurotrophic growth factor
Now, heres the tricky part. Although intermittent fasting may have its benefits, women are naturally sensitive to signs of starvation, so intermittent fasting for women is a whole different beast.
When the female body senses its headed towards famine, it will increase the production of the hunger hormones, ghrelin and leptin, which signal the body that youre;hungry and need to eat . Additionally, if theres not enough food for you to survive, your body is going to shut down the system that would allow you to create another human. This is the bodys natural way of protecting a potential pregnancy, even if youre not actually pregnant or trying to conceive.
Its not that youre intentionally imposing a famine upon yourself but your body doesnt know that. It doesnt know the difference between true starvation and intermittent fasting, which is why it defaults to this protective mechanism.
Therefore, some of the cons due to hormonal imbalances brought on by intermittent fasting may also lead to:
- Irregular periods
- Metabolic stress
- Fertility issues
- Difficulty sleeping
Ways To Plan Your Intermittent Fasting
There are several ways of doing intermittent fasting â all of which involve splitting the day or week into eating and fasting periods. During the fasting periods, you either drink fluids like fruit juices & water or have nothing at all.
Follow any one of these popular methods to start your intermittent fasting plan:
1. The 16/8 method: Many people find the 16/8 method to be the simplest, most sustainable, and easiest to stick to. Itâs the most common way of intermittent fasting as this pattern suits most people.
Also called the Leangains protocol, this method involves skipping breakfast and restricting your daily eating period to 8 hours. Say you pick your timing as 1â9 p.m., then you fast for 16 hours straight for the rest of the day.
2. Eat-Stop-Eat: This involves fasting for 24 hours, once or twice a week. For example, you skip breakfast for a day and then have it on the next day after one complete day of fasting. Take a gap of 1-2 days before your second fasting day and donât do it twice in a row.
3. The 5:2 diet: With this method, you consume lesser calories than on normal days, say only 500â600 calories on 2 non-consecutive days of the week, but eat normally the other 5 days.
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How To Start Intermittent Fasting
First of all, Id recommend checking with your healthcare provider to make sure intermittent fasting is appropriate for you, Maguire advises.
Once you have the green light from a medical professional, she suggests you start with a version of IF that isnt too drastic.
That might even mean simply closing the kitchen after dinner and opening it again for breakfast if youre used to snacking at night, Maguire adds.
Varady agrees, suggesting that people start with a 10-hour window for the first week, then move to 8-hour the second week.
From there, you can shorten your feeding window weekly if youre still feeling good.
Remember that you can start this window whenever it feels natural with your hunger cues.
If you wake up hungry, theres no reason to skip breakfast. You can eat in the morning and start your fast in the afternoon.
Hunger pangs are natural for the first week or two of fasting; coffee, tea, unsweetened seltzers, or flavored water can help assuage those pangs and habitual snacking.
Can Reduce Oxidative Stress And Inflammation In The Body
Oxidative stress is one of the steps toward aging and many chronic diseases .
It involves unstable molecules called free radicals. Free radicals react with other important molecules, such as protein and DNA, and damage them .
Several studies show that intermittent fasting may enhance the bodys resistance to oxidative stress 30319-3″ rel=”nofollow”>18).
Additionally, studies show that intermittent fasting can help fight inflammation, another key driver of many common diseases 30850-5″ rel=”nofollow”>19).
Studies show that intermittent fasting can reduce oxidative damage and inflammation in the body. This should have benefits against aging and development of numerous diseases.
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