Top 5 Mistakes to Avoid When Intermittent Fasting for Women Over 40 (Simple)

A while back, I wrote a post about intermittent fasting for women over 40. Most of the information is based on a video I had enjoyed from Thomas DeLauer. It includes tips that I don’t even follow like avoiding grains on fasting days and working out at a lower intensity when fasting. As I said before, people seem to like rules when it comes to health, so health experts make up rules for them! Obviously, some guidelines are helpful, that’s why I do what I do. I share what I am learning and what’s working for me because I wish I had known what I know now 15 years ago.

However, one thing that is becoming increasingly clear to me is: Fasting rules are meant to be broken. You will need to find what works for yourself. Nobody knows you the way you do. So, in this post, I am not giving women over 40 rules to follow when intermittent fasting. Instead, it’s a quick overview of some of the most common intermittent mistakes that you may be making and not know it.

By the way, don’t forget to check out my Intermittent Fasting 101 Workshop to learn more about how I lost 20 lbs using intermittent fasting after the age of 40.

Top Intermittent Fasting Mistakes for Women Over 40

First of all, how is intermittent fasting for women over 40 any different than younger women? Women over 40 tend to have a slower metabolism, may have hormonal imbalances, and may find it more difficult to change their lifestyle. These top intermittent fasting mistakes address some of these differences that affect women over 40.

1. Choosing a Fasting Window That Is Too Short

Women in general benefit from a longer fasting window that isn’t implemented every single day of the week, but particularly women over 40. Not only will a longer fasting window help insure that your caloric consumption decreases enough to lose weight (if that’s one of your goals), but it will also help you benefit from the metabolic switchover you want.


Switching to fat burning (or ketosis) is what I enjoy most about intermittent fasting. It is what makes it so effective at improving your metabolic health and losing weight. Most people start exhausting their glycogen stores after fasting for about 12 hours. However, for your body to produce enough ketones to be in ketosis, you most likely need to fast for at least 16-18 hours (unless you eat keto, of course!). Then, you would want to enjoy this metabolic switchover for a while. I tend to recommend a 20-24 hour fast for everyone, but women over 40 will find it even more helpful as they may struggle with insulin resistance.

Alternate-Day Fasting Benefits

Fasting longer and less frequently is an effective option for women over 40. Alternate-day fasting, in particular, has some major benefits. Alternate-day fasting has been shown to increase lifespan in mice. Also, a study where the metabolic effects of fasting were observed at the 12, 36, and 72-hour marks, found that the resting metabolic rate of the subjects increased at 36 hours. Read What Is Alternate-Day Fasting and Why It Works to learn more.

2. Not Cycling Their Diet and Intermittent Fasting Methods

If intermittent fasting for women over 40 involves longer fasts, it also means fewer fasting days. For example, with alternate-day fasting, once or twice a week would be a good goal. If you go for OMAD (One Meal a Day) or the Warrior Diet (fasting for 20 hours), I would recommend you some days off once in a while, particularly before your period. Again, I want to emphasize that I am not about making rules up. I do want you to be aware of how you feel on your fasting days. After you have gained enough fasting experience, you will know the difference between how you feel on different fasting days. Some days, you will feel hungry but you will be energetic and happy to keep fasting. Some days, you will feel weak and too hungry to fast longer. Listening to your body’s cues is an excellent way to cycle your fasting days.

Cycling Your Diet

Similarly to not always fasting the same length of time every single day of the month, it’s a good idea to change things up with your diet. For one thing, it will help you determine which way of eating makes you feel your best, but also, you will notice that your body craves different types of nourishment at different times. Sometimes, eating keto may be just what you need. At other times, you may want to include more carbs in your diet.

3. Not Eating Enough Protein

Again, learning to listen to your body will serve you well in this case. I like to break my fast with the Power Shake because it is light, satisfying, and filled with vitamins and minerals. However, I have noticed that sometimes, I crave meat to break my fast. Those days, I will eat some chicken breast or canned tuna. As I mentioned, intermittent fasting for women over 40 can be different due to the fact that women over 40 have to deal with a decreasing muscle mass. Increasing your protein intake may help preserve your muscle mass. The recommended protein intake for women is between 10 to 35% of your macronutrients, but as you age, you should aim toward the higher end of that range. Strength training is another effective tool to make sure you stay strong and to mitigate your muscle mass loss. Remember, you can combat muscle loss as you age, but you cannot gain experience unless you age! Let’s look at the bright side!

4. Not Drinking Enough Water

It’s easy to not drink enough water. You are busy and forget to drink. The first thing you should do any time you feel hungry is drinking a large glass of water. See how you feel after that. Most women need 74 ounces or a bit more than 9 cups of water a day. Did you know that dehydration is one of the ten most frequent causes of hospitalization for people over 65? I was surprised to learn that! Apparently, as you age, not only does your thirst sensation decrease but your renal water retention as well (Source: Hydration in the Aging).

5. Not Dealing With Sleep Issues

Poor sleep is another issue that tends to arise with age. Hormonal changes like the loss of estrogen and progesterone are contributing factors. If you have trouble going to sleep and staying asleep, be aware that there are things you can do to help improve your sleep. Implementing some sleep habits like going to bed early every night and turning off your screens an hour before bed are obvious ideas. It turns out that exercise is another excellent sleep aid. Make sure you exercise daily (not right before bedtime). Lastly, I have enjoyed a tart cherry concentrate as a means to sleep more soundly. Tart cherries are naturally rich in melatonin, the hormone responsible for good sleep.

Intermittent Fasting for Women Over 40 Video

In Summary

Intermittent fasting for women over 40 is not hugely different than for younger women. However, it’s important for more mature women to be aware of the natural biological processes that may make weight loss more difficult and affect overall health like a decrease in metabolism in muscle mass. Moreover, the decrease in progesterone and estrogen that accompanies menopause will impact sleep and cause weight gain. Fortunately, the answer is simple: intermittent fasting and exercise! And that’s what I am here to help you with.