Hormonal Changes And Menstrual Cycles
Some animal research suggests that intermittent fasting may lead to hormonal changes and undereating. In people with ovaries, these changes may negatively affect menstrual cycles and fertility .
However, most studies are old and have been conducted in animals. Human studies are needed to fully understand how intermittent fasting may affect reproductive health.
Furthermore, postmenopausal individuals may experience different effects from intermittent fasting. Menopause causes changes that can decrease insulin sensitivity and lead to weight gain, and intermittent fasting may help improve these outcomes .
Restricting daily food intake to a particular time window may cause increased food intake and weight gain, as well as short-term hunger and weakness. Older animal studies indicate that intermittent fasting may interfere with fertility.
What Is Intermittent Fasting And Why Would You Do It
Intermittent fasting is not a diet, it’s a pattern of eating. It’s a way of scheduling your meals so that you get the most out of them. Intermittent fasting doesnt change what you eat, it changes when you eat.
Why is it worthwhile to change when youre eating?
Well, most notably, its a great way to get lean without going on a crazy diet or cutting your calories down to nothing. In fact, most of the time you’ll try to keep your calories the same when you start intermittent fasting. Additionally, intermittent fasting is a good way to keep muscle mass on while getting lean.
With all that said, the main reason people try intermittent fasting is to lose fat. We’ll talk about how intermittent fasting leads to fat loss in a moment.
Perhaps most importantly, intermittent fasting is one of the simplest strategies we have for taking bad weight off while keeping good weight on because it requires very little behavior change. This is a very good thing because it means intermittent fasting falls into the category of simple enough that you’ll actually do it, but meaningful enough that it will actually make a difference.
How To Avoid Low Energy
Acclimating to intermittent fasting is similar to acclimating to the keto diet. In both cases, anything that helps you move toward fat-burning mode will help you make the transition. Supplementing with MCT oil, coconut oil, and other healthy fats may help with ketone production and overall acclimation.
Upping your caffeine intake a little may also help you avoid low energy, since caffeine helps your body mobilize fatty acids as fuel.
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How To Plan Your 1: 8 Fasting Schedule
So, what 16:8 fasting schedule will suit you best? No matter when you choose to fast, it should include your sleep hours. To determine what hours are best for you, ask yourself:
- Which meal is essential to me?
- How do I feel if I miss this meal, or if its late or early?
- What part of the day do I feel most hungry?
Try to schedule your fasting period when you tend to be less hungry and least likely to eat otherwise, you might break your fast too early or overeat during your eating window.
Once youve identified the most vital part of your day for your eating window, choose what time you want your window to begin and end. For instance, if youre going to skip breakfast or eat a late breakfast and early dinner, you might set your eating window from 11 am to 7 pm. And if you cant start your day without breakfast, you might choose to eat from 9 am to 5 pm.
Simply put, pick start and end times that work best for you and stick to them. Youll feel better if you follow a set schedule, and youll be more likely to stick to your fasting plan.
Exercise While 1: 8 Intermittent Fasting
Yes, you can exercise while practicing the 16:8 intermittent fasting method as long as you provide your body with the nutrition it needs during your eating window.
For hard HITT workouts and 60 and 90+ minute cardio sessions its recommended you fuel your body for this activity.
If you live an active lifestyle and want to know how to incorporate intermittent fasting into your routine safely without sacrificing fitness this is for you!
Intermittent Fasting for Women
If you want to dive deeper, Ive created a book with everything you need to know about intermittent fasting & a 1-week meal plan so you know exactly what to eat during your eating windows. Check out my Intermittent Fasting Guide here.
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How The 1: 8 Fasting Schedule Works
The 16:8 fasting plan is an eating schedule in which you fast for 16 hours each day and eat during an eight-hour window. This eating schedule comes with all the benefits of other fasting schedules . Perhaps even better, you pick the eating window.
So what should that eating window be? “There’s actually infinite variability. It can be any time. Any time that you don’t eatthat’s fasting,” explains Jason Fung, M.D., fasting expert and author of the book The Complete Guide to Fasting.
If you can’t live without breakfast, slot your food earlier in the day . If you prefer an early dinner, eat in the middle of the day . If you’re someone who regularly goes out with friends for late dinners, schedule your eating hours later in the day .
Contrary to popular opinion, there are no rules around how many meals you have to squeeze in or whether or not you have to include breakfast. In fact, no data actually proves breakfast makes you healthier or weigh less.
What Ramadan Can Teach Us About Intermittent Fasting
During the holy month of Ramadan, observant Muslims fast every day from sunrise to sunset for about 30 days. The fast-breaking evening meal is often a big dinner.
Over the years, researchers have studied observant Muslims in an effort to find out how fasting affects a range of outcomes, including athletic performance. As it turns out, Muslim athletes tend to do worse in the early weeks of a Ramadan fasting schedule, research finds.1
How someone performs depends on several factors:
- The individual athlete: Just as some athletes can train harder and longer than others, some also adapt to fasting more easily and more quickly than others. Hello, genetics.
- Recovery and nutrition: Adequate rest, sleep, hydration, and nutrition can all help the body to adapt more quickly to IF and heavy training.
- The fasting schedule: Less intense types of fasting pair better with heavy exercise than more intense styles of fasting.
- The type of exercise. Fasting is more likely to negatively affect more intense training. .
The following activities generally dont pair well with IF. If any of these are your jam, you can probably expect your performance to suffer as your body adapts to this new way of eating:
- activities that require intense effort
- speed endurance, such as repeated short, intense runs in soccer
- repeated power-explosive movements like jumping
- some types of strength and work capacity
But its not all bad news.
Pairing exercise with IF can boost results, too.
Is Fasting 16 Hours A Day Healthy
Its also theorized that fasting gives your vital organs, digestive and absorptive hormones, and metabolic functions a break, according to a recent study published in Cell Metabolism. Since our bodies secrete insulin to help our cells absorb sugar, fasting is linked to reducing our susceptibility to insulin resistance over time.
However, research has also linked fasting to increases in LDL cholesterol . Intermittent fasting can make you feel dizzy and nauseated and cause periods of low-blood sugar and dehydration. Despite the fact that most 16:8 enthusiasts drink water during fasting periods, it may not be enough .
I also have a much deeper concern about the disordered eating behaviors that may arise from intermittent fasting. Research shows that fasting for a period of time followed by a limited window for eating primes you to overeat. It’s a cycle that can be difficult to get out of because it impairs our body’s natural hunger cues and metabolism. Restricted eating may also lead to an increased risk of depression and anxiety.
Intermittent Fasting Is Not Enough To Keep You In Ketosis
The 16/8 fasting window may not be enough to get you into or keep you in ketosis. Even if you do end up in ketosis, if you continue to eat a diet with even a moderate amount of carbs itll probably kick you out of ketosis each time.
This can result in unpleasant side effects such as the keto flu and being overly hungry each time you start fasting again.
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Should You Try 1: 8 Fasting
Ultimately, it’s a personal choice. But there are a few beneficial behaviors you can try without committing to the riskier elements of 16-hour fasts. The first is to better understand mindfulness and how it relates to your food choices. To get started, consider these questions when you’re deciding when and what to eat:
Where are you physically when you decide to eat?
Many of us eat based on scenario, not hunger levels. Case in point: Raise your hand if youve ever gone to the movies after dinner and suddenly wanted popcorn? Yep, me too!
By considering the moments when you eat, you may become aware of patterns you didn’t notice before. Say youre a person who loves to graze during The Bachelor. If youre fasting after 8 p.m., youve automatically cut hours and subsequently, calories from your post-dinner snacking.
Are you getting enough sleep?
If you’ve cut out late-night snacking, that alone could help you go to bed earlier a very crucial component to any weight loss plan. Getting seven hours of sleep per night has been linked to better weight management, reduced risk of chronic disease, and improved metabolism.
/8 Intermittent Fasting Tips
Many people need an adjustment period to get used to fasting for 16 hours, Dr. Mattson notes, adding that you might feel irritable and hungry during that time. Such feelings often improve within four weeks or so, he says.
You may also need a little while to figure out how best to approach eating within your eight-hour window. It comes down to your appetite, Harbstreet says. A little trial and error with the approach is a good ideawhether you go with three meals in the eight hours, or two meals and a snack or two.
Your needs and preferences might vary somewhat from day to day, but having a general sense of your preferred approach will help you make a plan for what to eat when.
Read Also: What Not To Eat On Intermittent Fasting
Diet: Does Intermittent Fasting Really Work And Should You Try It
Intermittent fasting, especially the 16:8 diet, is extremely popular. Does it work?
ByMatt Evanspublished 18 December 20
Intermittent fasting is one of the most popular dietary methods around. Hugh Jackman swore by it when getting into scissor-clawed shape as Wolverine for the X-Men movies, but it’s not just Hollywood stars that enjoy the benefits of intermittent fasting, as the 16:8 diet has become extremely popular in recent years.
But what is intermittent fasting, and how does it work?
Intermittent fasting is the process of abstaining from food for a certain amount of time every day, cramming your calories into a smaller window of time. The 16:8 diet in particular suggests we fast for 16 hours every day, eating only within an 8-hour window. This ensures we are sated during the eight hours in which we are permitted to eat, but the shorter time window usually means we consume less calories each day.
The science is certainly in favour of intermittent fasting: one study, published by researchers from the University of Illinois, Chicago, looks at the effects of intermittent fasting on weight loss and blood pressure. The 23 volunteers followed the 16:8 diet for 12 weeks, eating between the hours of 10am and 6pm, abstaining from food for the rest of the day.
Pointer #: With Demanding Fasting Schedules Decrease Workout Intensity
Precision Nutritions Director of Curriculum, Krista Scott-Dixon, PhD, learned this lesson the hard way when she started fasting twice a week. Upcoming Brazilian jiu-jitsu competitions created pressure to cut weight, so she kept her exercise regimen pretty intense.
I was cycling and running several hours a week, often while fasted, she says. I thought I was being a badass. In reality, I was being foolish, and doing everything Id tell clients not to do.
She experienced insomnia, heart palpitations, anxiety, and horrible mood swings, as well as some budding stress fractures.
Let her story be a cautionary tale.
Its easy to fool ourselves into thinking well be the exception to the rule. All too often, we eventually find out were the rule after all.
What actually counts as too much exercise will depend on you, but a good general guideline would be:
- no more than 3-4 hours a week of heavier resistance training
- no more than 2-3 brief sessions of metabolic conditioning a week
- no more than 1-2 hours a week of moderate intensity cardio
Recommended Reading: How Does Fasting Make You Lose Weight
What Is 1: 8 Fasting
16:8 stands for 16 hours of fasting and eight hours of eating in 24 hours. So, you fast 16 hours of the day, then consume all your daily nutrients in an eight-hour window.
Sixteen hours may sound like a long time to go without food until you learn youll sleep for seven to eight hours out of the 16. Not so bad, right?
So, if youre intrigued by the idea of intermittent fasting but are concerned about fasting for 16-hours straight, it may be easier than you think.
What Exactly Is The 1: 8 Diet
Its pretty simple. Basically, during your 16-hour “fasting” period, you limit yourself to black tea, coffee, or diet soda. Then, for the next eight hours, you can eat whatever you want . That’s it.
Scientifically, at least, the 16:8 diet seems to check out. In a recent study published in the journal Nutrition and Healthy Aging, 23 obese men and women followed the 16:8 diet for 12 weeks. Compared to a group that ate normally, those on the 16:8 diet took in 350 fewer calories per day, lost a modest amount of weight , and lowered their blood pressure.
But, keep in mind: This was a small study and few others have examined the 16:8 diet specifically, so its tough to draw any firm conclusions just yet. More research needs to be conducted before we can see if and how it can be implemented into an actual plan effectively, confirms Beth Warren, RDN, founder of Beth Warren Nutrition and author of Secrets of a Kosher Girl.
Still, other types of intermittent fasting show promise. The 5:2 diet, for example , resulted in more weight and fat loss compared to day-to-day calorie restriction in a 2017 study in the International Journal of Obesity.
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What To Eat During Intermittent Fasting 16/8
Though intermittent fasting isnt a diet in the sense that there are food-specific restrictions imposed, it is recommended that you eat as many whole foods as possible and avoid processed foods. The quality and nutritional value of food matters greatly when practicing any kind of health plan, advises Wandzilak.
According to Grant, what you choose to eat will depend on your goals. When doing any type of fast, water is the most common beverage to consume during your fasting period. However, if youre looking for a lifestyle rebootor if your goal is weight losscoffee or tea is acceptable during fasting periods as well.
If gut rest is your ultimate goal with fasting, then no food or beverages, aside from water, should be consumed during a fast, explains Grant. However, if longevity, weight loss or metabolic benefits are your goal, then sometimes a few calories, such as plain coffee or tea, can be consumed during your fasting period without having much of a negative impact on the outcomes.
Most experts agree that standard diet recommendations are also encouraged when intermittent fasting, though Grant specifies that prioritizing protein during your first meal of the day can help your body as it rebuilds and repairs as it prepares to once again enter the digestion phase.
Intermittent Fasting 16/8 Risks
As with any diet plan, you should begin by consulting your doctor. Grant specifies that everyones body responds differently to intermittent fastingdue to genetics, current health, pre-existing conditions, and lifestyleand isnt recommended if you have Type 1 diabetes, are pregnant or have a history of disordered eating. Speaking to your doctor and consulting a nutritionist or dietitian is beneficial if you are unsure of how to approach intermittent fasting or are looking for guidance personalized to your lab work and specific goals.
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It is important to know that researchers admit further research is needed in specific areas of intermittent fasting. For example, most research has been performed on overweight and middle-aged adults. Additionally, some research disputes that intermittent fasting is an effective eating method for those whose goal is losing weight. This study, however, was conducted in overweight and obese adults, further proving the need for studies to be conducted on people whose weight falls in the healthy range. With this in mind, its important to work with your doctor is the key to understanding if intermittent fasting will work for you and your specific goals.
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