Intermittent Fasting: Is it Dangerous for Women?Last Updated: March 18, 2019
There is a lot of buzz behind Intermittent Fasting, or IF, these days. In its purest form, it essentially allows you to eat whatever you want while helping you lose weight, sleep better, and feel emotionally healthier - just not whenever you want. The idea is to trick your body into functioning more efficiently and producing fewer stress hormones by controlling when exactly you eat your daily meal(s).
Obviously, it should go without saying that eating "whatever you want" should be within the realm of what is appropriate for your height, weight, and age, which is somewhere around 2,000 calories/day. It should also contain the right ratio of proteins, fats, and carbs, as well as plenty of high-fiber fruits and vegetables. However, there are still some out there who think that altering the "when" part of your diet in the name of IF is actually unhealthy.
But is it really all that bad? Are these "IF is Dangerous" studies just attention-grabbing headlines, or are they actually based on hard science? Below, we'll look at some of the data which has been collected on the subject and weigh in with our experience.
Why Some Believe that Women Should Avoid Intermittent Fasting
According to some sparse and incomplete studies on the matter, IF is allegedly dangerous for women because it might:
- Negatively Affect Female Reproductive Health. In studies on mice, female rodents on calorie-restricted, alternate-day fasting diets became "masculinized", experiencing ovarian shrinkage and irregular uterine cycles.
- It may not have the same insulin benefits in women as men. In a 41-participant study on obese patients, men experienced a beneficial change in insulin responses, whereas the women did not.
- When combined with calorie restriction, certain parts of the brain (in mice) react differently in males and females. Again, in studies on mice, female rodents experienced sleep deprivation while fasting - but it also improved their cognitive function and memory in ways that were not observed in the males.
Why Many Women Do It Anyway
First of all, as scary as some of those results above may look, you have to take the results with a grain of salt - for several reasons. For one, most of these studies were performed on mice, not actual humans. So there are certain variables at play which studying mice cannot predict.
Secondly, most of the data on female test subjects of reproductive age was either excluded, or those subjects weren't allowed in on the study in the first place. And their reasoning for doing so was because, in so many words, the unpredictability of female hormones would have corrupted their data.
Lastly, there are still a whole host of health benefits that females and males alike can get from intermittent fasting - if you do it right. Below, we'll suggest some helpful tips you can follow to get the most out of IF with few (if any) of the negative consequences mentioned above.
How Females Can Avoid Negative IF Complications
You should probably avoid intermittent fasting if you are pregnant, wish to become pregnant in the very near future, or are still breastfeeding. Likewise, if you have any sort of hormonal disorder, or if you are on any type of hormone replacement therapy, IF may not be for you. Intermittent fasting, especially extreme regimens which involve massive calorie restrictions and/or alternate-day fasting, could potentially compromise your ability to produce hormones in healthy, balanced levels (according to the studies mentioned above, that is).
Start slow, especially if you are new to IF. Make sure you are eating at least once per day, and give yourself a generously wide food window. It might be unwise to start with anything smaller than an 8 hour food window if you have never done IF before. Also, don't restrict your calories at first. Start by restricting your 2,000 calories/day consumption (or whatever is appropriate for your height, weight, and age) to your food window, and only reduce your daily calories if you don't see results after the first 2-3 weeks.
Slowly incorporate exercise into your IF routine. After all, an IF regimen is ideal for someone with a busy schedule who doesn't have hours of idle time during the day to slave away at the gym. Remember, one of the main benefits of IF is that it stimulates hormesis. Hormesis happens when your body responds to low-level stress by making positive changes, such as processing glucose more efficiently. But once you put too much stress on your body, such as restricting your calories and over-exercising, you lose all of the positive benefits of hormesis and start to produce excess amounts of stress hormones. This, in turn, will compromise your weight loss and fitness goals.
Lastly, listen to your body. If you've been successfully following an IF routine for a while now with positive results, don't let some mice in a lab somewhere convince you that you need to stop IF immediately. On the other hand, if you've been struggling with IF and can't seem to get a good routine down, then feel free to walk away. There is no one perfect diet and/or exercise routine that is right for everyone. Making sure you find the right regimen for your specific needs and goals should take priority above all else.