Because of intermittent fasting’s success, its rise to fame in the past few years has been something notable. We’re fans of this eating rhythm and utilize it whenever it makes sense. However, it’s important to understand it not just in basic terms, but in terms of our personal health and bio-individuality.
“The idea behind intermittent fasting is simple: you eat all your calories within a specific window—for example, between 12 p.m. and 6 p.m.—and you fast outside of that time. Switching between fasting and feasting can turn on your brain and improve cellular function across your body. A lot of people find it’s useful for losing weight, too,” Dr. Taz starts.
And that’s the appeal. It’s fasting, without fasting. We get to eat everything we need without forgoing nutrients, but in a smaller window of time, giving our bodies a longer fast period. This helps with detox, but most notably, weight loss. Sounds easy and enticing, right?
“But intermittent fasting may not be for everyone. Women, in particular, can struggle with intermittent fasting, especially when we’re in certain parts of our cycles,” Dr. Taz says.
“While intermittent fasting is amazing for some women, for others it can interfere with hormones and energy levels. As an integrative physician, I’ve worked with thousands of women who want to improve their diet and lifestyle for better health. Some of my patients have had great success with intermittent fasting, while others have not.”
There are several benefits of intermittent fasting for women, according to Dr. Taz:
• Weight loss. A lot of people find that it’s psychologically easier to be hungry for a portion of the day, then to eat all their food in a shortened window and go to bed fully satiated.
• Lower inflammation. Fasting turns on autophagy, a process that’s like spring cleaning for your cells. During autophagy, your cells sort through all their parts and replace anything that’s old or damaged. You end up with stronger, younger cells that work the way they should. Autophagy also decreases inflammation.
• Mental clarity. Fasting triggers profound brain autophagy and also decreases brain inflammation, which could explain why so many people report a boost in mental clarity and focus when they fast.”
The reason this isn’t a broader dialogue in the wellness world is that intermittent fasting, like most things, isn’t tested on young, menstruating women, but rather men and post-menopausal women. That is because women with an active menstrual cycle have many more variables, which would cause the testing of this theory to take much longer, be more detailed, and be more expensive.
The cons of intermittent fasting for women, according to Dr. Taz:
• “Hunger and cravings. As women, our hormones play a huge role in our wellness, and how we feel fluctuates throughout the month. In certain parts of your cycle, you may be hungrier than usual and have especially strong food cravings. Fasting may not be your best option during those times.
• Period issues. Some women who fast every day may lose their periods or have other cycle disruptions.
• Thyroid stress. Fasting can cause changes in your thyroid hormone production. The shifts are small enough that it shouldn’t be an issue if your thyroid is healthy—but if you have an autoimmune condition like Hashimoto’s or any other thyroid imbalance, you may want to skip intermittent fasting.”
It’s vital for premenopausal women to be aware of the stages of their cycle and what their bodies need during that time, as well as be intuitive about these needs.
For example, during a woman’s luteal phase, otherwise known as the time that PMS occurs and when the bleed begins, fasting of any kind might produce more harm than good. Alisa Vitti, functional nutrition and women’s hormone expert and founder of FLO Living, explains that “because women’s bodies are biologically built for fertility and reproduction, extended periods without food tell the body that now isn’t a good time for reproduction.”
If this seems irrelevant to someone who is not trying to get pregnant, reproductive health isn’t just about making a baby. It’s about all of our hormones that regular our health and bodily systems. For women, intermittent fasting can disrupt estrogen balance and throw off all our essential physiological processes, doing the opposite of what we want. It can even cause weight gain, if not managed correctly.
It’s important to pay attention to what works for you, but the general rule of thumb is to not fast for consecutive days; pick three out of the week and split them up. Also, do not fast when bleeding or when premenstrual symptoms are creating a heightened sense of hunger.