Intermittent fasting is a diet technique that has been growing in popularity in the last decade. Many different variations to intermittent fasting exist, but the most common include restricting when you eat during the day.
This typically means eating in an 8-hour window (i.e., only during certain hours) and fasting for the remaining 16 hours. Some people choose to not eat anything at all during their fast, while others will drink coffee or other non-caloric beverages.
Depending on the person, many different health benefits have been reported with intermittent fasting including weight loss, improved insulin sensitivity, and reduced inflammation.
Although there are no randomized controlled trials that look at women specifically, we can still gain some knowledge from animal and human studies including both men and women.
Intermittent Fasting For Women?
In the past, scientists used to think that intermittent fasting was not safe for women, including pregnant and breastfeeding women. However, more research has revealed that this isn’t the case.
In one study, intermittent fasting did not pose any major risks to healthy women who were either pregnant or breastfeeding.
Another recent review of studies on fasting and its effects on female hormones found no reason for concern and suggested that it would be beneficial for fertility and long-term health.
The one exception is that pregnant or breastfeeding women should not follow a fasting schedule that restricts food intake to less than 500 calories each day, as this could cause nutritional deficiencies in the mother and child.
Still, women who are very lean or underweight may need to be careful with intermittent fasting, especially if they are exercising regularly or are very active.
As mentioned, your body’s physical response to calorie restriction may be different depending on how much fat you have in your body. As a general rule, the leaner you are, the less likely it is that intermittent fasting will cause you to lose lean mass rather than fat mass.
Body Composition Results From Intermittent Fasting
Several short-term human studies (ranging from 2-16 weeks) have shown that intermittent fasting can lead to weight loss, although this may be due to decreased food intake in general as opposed to specifically because of fasting.
20 hour fast
In addition, one study showed that obese women following a 20 hour fast experienced fat loss and overall body fat reduction as compared to those eating normally. No significant reduction in fat mass was found in males completing the same protocol, however.
Benefits of continuous calorie restriction
Other studies have shown that intermittent fasting may also lead to a reduction in overall body weight as well as waist circumference, without a decrease in lean body mass (as expected with calorie restriction). This suggests that intermittent fasting may prevent an increase in bodyfat as we often see with continuous calorie restriction.
Preservation of muscle
Research has also shown that intermittent fasting can result in better preservation of lean body mass (muscle) during weight loss, which is likely the main reason why it works so well.
The reasoning behind this is that when we lose weight and body fat, we usually lose a lot of muscle as well unless an intense resistance training program is followed.
Since intermittent fasting can result in a more suitable environment for muscle growth, this is another advantage to following the eating pattern.
Intermittent Fasting and Cognitive Function
The brain adapts to a variety of different energy substrates and relies on both glucose and ketones for fuel. Studies have shown that when in a state of ketosis (which you will be in if you have been fasting or limiting your carbohydrate intake), that the brain may become more neuroprotective and resistant to dysfunction.
In addition, intermittent fasting has been shown to protect against cognitive damage associated with reduced blood flow to the brain (i.e., when you hold your breath).
Intermittent fasting can also have an effect on neuro-inflammation, which is the inflammatory response produced by glial cells in the brain. This can result in an improvement in cognitive function and overall reduction of risk for many different brain disorders.
Prevent an increase in AGEs
A recent study also showed that intermittent fasting was able to prevent an increase in AGEs (advanced glycation end products) within the brain, which are compounds that have been shown to play a role in the development of Alzheimer’s.
Memory recollection and recognition
Another study found that intermittent fasting was able to improve cognitive function in terms of memory recollection and recognition as well as reducing blood glucose levels.
This suggests that following an eating pattern where you are not constantly elevating your blood sugar can have benefits for cognition.
Intermittent Fasting and Insulin Sensitivity
One of the main reasons intermittent fasting shows so much promise is because it can lead to an improvement in insulin sensitivity.
Studies have shown that following an intermittent fasting schedule where calories are limited to 700-900 per day can increase insulin sensitivity by over 75%, with the greatest changes seen in people who are obese or overweight.
To put this into perspective, it means that if your insulin sensitivity is initially “normal” at 100 units per milliliter of blood, then after a week of intermittent fasting with a limited 700 calorie per day diet it can increase to 175 units/ml. That’s pretty impressive!
Higher energy levels
This improvement in insulin sensitivity is one reason why many people feel better while following this eating pattern. When you follow an intermittent fasting program like the Eat Stop Eat diet plan, your energy levels may be more even throughout the day and you will experience fewer cravings since insulin sensitivity is improved (cravings are usually tied to blood sugar fluctuations).
The fact that intermittent fasting can lead to such significant improvements in insulin sensitivity demonstrates how powerful this eating pattern can be for overall health and weight loss.
Remember that these improvements also occur within just a few days of beginning to limit your daily calorie intake, but the more weight you have to lose the greater the benefits will be.
Reduce Chronic Inflammation
Chronic inflammation is an underlying factor in many diseases ranging from arthritis to heart disease. Intermittent fasting has been shown to help reduce markers of inflammation within the body, which can benefit overall health and may also play a role in improving insulin sensitivity.
What Is Intermittent Fasting?
Intermittent fasting is a form of dieting in which calories are limited for a certain period of time. There are several different intermittent fasting schedules, all of which involve splitting the day or week into eating periods and fasting periods.
For example, you might eat only between the hours of 11 am to 7 pm each day for 4 weeks. You would then follow this eating pattern for 4 weeks and then take 4 days off from any calorie restriction to eat whatever you want.
The 8 Hour Diet?
One popular version of intermittent fasting is the “8-hour diet” – which limits your eating to an 8-hour window each day (such as 11 am-7 pm) and then fasts for the remaining 16 hours. There are several different variations on this meal pattern, with some programs recommending a 9-hour fasting window and others a 10-11 hour window.
Eat Stop Eat
Another form of intermittent fasting is called Eat Stop Eat, which involves fasting for one full day (24 hours) once or twice per week.
With this eating pattern, you would eat normally for the first 20-23 hours of the day and then restrict your calorie intake for the remaining 1-2 hours. You can choose to go without food completely during your fast, drink water only, or eat very small amounts of low-calorie foods (such as vegetables, soups, and some types of fruits).
Another form of intermittent fasting is called the “Warrior Diet”, which involves splitting the day into a period of fasting followed by a period of eating. With this meal pattern, you would eat during an 8-hour window (such as 11 am-7 pm) and then fast for the remaining 16 hours of the day.
This version of intermittent fasting involves eating within a restricted time frame each day. A popular form of this meal pattern is called the “16:8 diet”, which involves splitting the day into an 8-hour window for eating and a 16-hour fast (such as 11 am to 11 pm).
There are several variations on this program, including 18:6 and 20:4. Research has found that the shorter eating windows in these programs may help to reduce insulin resistance and burn fat stores.
Another form of intermittent fasting is called alternate-day fasting, which involves alternating between periods of normal eating and fasting regularly (such as every other day). For example, you could eat normally for 24 hours and then fast for the next 24 hours.
This meal pattern is effective at reducing body weight, waist circumference, triglycerides (blood fats), insulin resistance, blood pressure, and markers of inflammation within the body. Most research suggests that this eating pattern is superior to simply restricting calories every day in both weight loss and long-term health benefits.
This form of intermittent fasting restricts your calorie intake every week rather than every day. You would eat normally for 6 days in the week, restricting calories to about 25% of your usual needs on a remaining day (about 500 calories for women and 600 calories for men).
Fasting Mimicking Diet
The Fasting Mimicking Diet is a low-calorie eating pattern designed to provide the same effects as an extended fast. It’s intended to be used 2-3 times per year for 5 days at a time. The diet consists of specific quantities of plant-based foods, vegetable shakes, and herbal supplements.
The 5:2 Diet
Another form of intermittent fasting is called the “5-2” diet. With this approach, you fast for 2 days each week and can eat normally on the other 5 days. This program may be quite simple to follow if you are already used to skipping meals occasionally.
Regardless of which version of intermittent fasting you follow, the overall result is that you are limiting your total calorie intake for a specific amount of time each week. One reason intermittent fasting shows so many benefits compared to other weight loss methods is that it doesn’t rely on severely restricting the number of calories you consume (which often leads to bingeing).
Many people find this approach easier to maintain than other types of diets since they don’t have to worry about calories, portion sizes, or following an organized meal plan.
Choosing A Fasting Schedule
If you’re interested in trying intermittent fasting, then one decision that you will need to make is how long your daily fast will be. While many people choose the 8-hour window mentioned above for convenience, others opt to fast for 20 hours each day.
The longer you go without eating during your intermittent fasting period, the more benefits you will get since your body enters into a deeper level of fat-burning than when only fasting for several hours.
Also keep in mind that if you are very active or do high-intensity workouts, then you may want to shorten your fasting window so that you are eating more frequently. Working out during a fasting period can be difficult since some research suggests that exercising while fasted may cause the body to burn muscle tissue for energy.
When To Start Intermittent Fasting?
You can choose to try intermittent fasting at any age or if you are at a normal weight. However, keep in mind that you will probably experience the most benefits if you start during a time of your life when your schedule and lifestyle allow for it (such as young adulthood).
Notably, research suggests that intermittent fasting is not appropriate if you are underweight, have low bone density or muscle mass, or suffer from a chronic disease or medical condition. If you have a history of eating disorders, then it may be best to avoid intermittent fasting altogether – just in case there is any confusion about its effects on weight loss and health.
Intermittent Fasting For Weight Loss?
Another major advantage of intermittent fasting is that it can be a very effective weight-loss method.
For many, simply not eating for most of the day and reserving their calories for when they are most active throughout the week may help them start losing weight right away. During the few hours in which you are eating each day, you may find that your appetite is reduced due to the natural effects of calorie restriction.
On top of this benefit, there are several others to intermittent fasting too. For instance, studies suggest that it can reduce LDL cholesterol levels and blood pressure while increasing insulin sensitivity (all risk factors for heart disease ). It may also help with brain function by protecting neurons against certain types of stress and reducing inflammation throughout the body.
Intermittent fasting may also help reduce appetite and hunger levels, making it easier to stick with a calorie-restricted diet. (Some studies show that non-caloric sweeteners like aspartame, sucralose, and saccharin can increase appetite by tricking the body into believing that you are ingesting carbohydrates.)
Finally, intermittent fasting is also considered to be a simpler diet plan, both in terms of meal planning and ease of compliance.
For example, it is easier for most people to fast during the day than it is to count calories and track their intake at every meal. All in all, intermittent fasting may help you lose weight by making your life simpler!
Intermittent Fasting Benefits for Women Live Event Video
Great video- “Talking intermittent fasting because it is crazy popular right now we’ve been getting so many questions about it and so we kind of want to take this time to debunk”.
Hey guys Ashton Kelley here from Really Fit we are talking intermittent fasting today because it is crazy popular right now we’ve been getting so many questions about it.
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