Intermittent fasting is one diet trend that many are familiar with. Some people swear it will fix every health ill there is. What I find amusing is that if you sleep at night, then you are already technically intermittent fasting, but let’s get deeper into it.
What is Intermittent Fasting?
Intermittent fasting (IF) is all about when you eat, not what you eat. It typically involves time-restricted eating—like finishing dinner early and delaying breakfast—or fasting for 24 hours a few days a week.
Typically, the IF participant plans to fast for a specific block of time each day, such as 16 hours. They will then eat all their meals and snacks within a set 8-hour window.
The Misinterpretation of IF
In my clinic, I have a lot of clients who have experimented with IF. I usually see a few common patterns:
- The client forgets breakfast and decides it’s better to eat less anyway, then delays lunch and spends the evening eating everything since they are starving.
- The client wants to lose weight, so they try IF. They start with an 8-hour eating window, but eventually are down to 3 or 4 hours. They are tired, exhausted, and have a miserable relationship with food.
- The client will only eat highly palatable foods during their eating window because they are constantly thinking about their next meal and when they can finally eat, and they feel miserable.
I have heard other professionals call IF a socially acceptable form of anorexia. I think they are on to something. What I see most commonly is that people are hearing about IF and interpreting it as “we all overeat,” so they try restriction in various forms.
The trouble with this poorly planned approach is that your body hates it. IF should be followed with intention and care. It should be used for specific purposes under the care of a qualified Certified Nutrition Specialist who understands disordered eating, and what your goals are for using it as part of your plan to take care of your body and health.
When IF Helps Women
Some research suggests there may be instances where using an IF approach can be beneficial for specific medical conditions.
1. Post-Menopause & Metabolic Health
After menopause, women can benefit from IF—studies report improved insulin sensitivity, reduced inflammation, and better blood pressure.
2. PCOS & Insulin Resistance
Time-restricted feeding may support hormone balance in PCOS. Small trials show improved insulin levels, reduced testosterone, and regular menstrual cycles. What I have seen for my PCOS clients, however, is that most are more successful with a high-protein breakfast and regular, balanced meals throughout the day.
3. Circadian Rhythm
There is some evidence that IF may help regulate circadian rhythms, making it easier to sleep at night. As sleep improves, so do many other health markers, such as cardiovascular health and blood sugar management.
When IF Can Backfire
1. Hormonal Disruption in Pre-Menopausal Women
Fasting can impact estrogen and progesterone via GnRH suppression, leading to cycle irregularities, mood shifts, and low libido.
2. Risk of Disordered Eating
Because IF is socially acceptable, it’s easy to slip into extreme restriction. People, and women in particular, with a history of disordered eating are especially vulnerable. So if you use IF, be sure to do it with the support of a provider who is informed about your health and your history.
3. Energy Crashes & Stress
Skipping breakfast can raise cortisol levels, lower blood sugar, and leave you feeling foggy or irritable. Some studies even link morning fasts to higher cardiovascular risk.
Women and Regular Meals
In my experience, countless women—especially those managing PCOS—feel stronger, calmer, and more hormonally balanced when they eat breakfast and at regular intervals throughout the day.
That morning meal acts like fuel, stabilizing blood sugar and setting a positive tone for the day. Skipping it often triggers cravings, emotional ups and downs, or afternoon fatigue.
So, while we can see that there is some research indicating that IF may be appropriate in some instances, none of these studies took into account the toll IF can have on mental health.
Diets like IF are founded on principles of restriction, which is something our bodies and minds hate. For example, if I told you right now that you can never have ice cream again, you would likely rebel at some point because “you’re not the boss of me.”
In many instances, IF leads to worsening mental health and a complicated and disordered relationship with food. Particularly when IF is not done intentionally and with the proper support in place.
Using a Different Approach for Better Long-Term Results: Intuitive Eating
I would be remiss if I didn’t point out that your body is equipped with all the knowledge it needs to help you properly fuel it. We are born intuitive eaters; we lose touch with this instinct over the years.
The benefits that can be achieved through IF can also be achieved through intuitive eating, and it comes with the bonus of helping us improve our relationship with food and our bodies.
Intuitive eating is the ability to understand our body’s innate cues. Not only does it help us recognize hunger and fullness, but through this process, we also become more aware of emotions as they play out in our bodies.
Being more connected to the body and mind has many mental and physical health benefits.
A Fair, Practical Approach
1. Know your phase of life
IF is generally more forgiving post-menopause. For peri-menopausal or menstruating women, IF can come with hormonal costs.
2. Customize to your needs
If PCOS and insulin resistance are part of the picture, a time-restricted window of 12–14 hours may offer metabolic benefits—especially when breakfast is included (smartfertilitychoices.com). However, watch your relationship with food and make sure things feel good both mentally and physically.
3. Watch for red flags
Mood swings, menstrual disruption, low energy, obsession around food—these are signals your body may be out of balance.
4. Find support
If trying IF is something you are determined to do, find a Certified Nutrition Specialist to help you along the path and explore whether that is the best option for you.
My Final Take as a Certified Nutrition Specialist
Intermittent fasting is a tool—not a rule. Used thoughtfully, it can support hormone balance, insulin sensitivity, and even gut health for certain women. But left unchecked, it can mimic the very restrictive culture we’re working to dismantle. Listening to your body, supporting your cycle, and embracing flexibility will always serve you better than rigid fasting schedules.
We need to find ways to eat that help us feel our best while allowing for flexibility. IF is a fad diet that gets abused, but there is a time and place for it. Listen to your body and your intuition as you work to improve your nutrition and diet.
If you are thinking of trying IF, or you need help to find a better way to approach your health and nutrition, let’s talk. I have lots of personalized options, and I would love to help you on your journey. You can schedule a free consultation with me, and we can either meet in my office in Bountiful, Utah, or online. I’m looking forward to talking with you.