There is so much conflicting information about intermittent fasting on the internet! Many male health experts swear by it, while most experts in women’s health say to avoid it. How can we get the benefits of intermittent fasting while keeping our hormones balanced? I needed to find out.
What is Intermittent Fasting and Time-Restricted Feeding?
I keep hearing more and more about intermittent fasting (IF). The idea is that you have periods when you’re not eating as much as you usually do. IF examples include reducing calories for two consecutive days, or skipping meals, or even doing a full day of only drinking water.
When I first heard about it, it seemed wrong and shocking! In the past, everything said that six meals spread out through the day is the best way to lose weight, and I lived by that for a long time. But when I started thinking about what our paleo ancestors did, they were NOT eating six small meals a day. Our bodies are made for feast and famine since that is how we evolved.
Time-restricted eating is a form of intermittent fasting when you shorten your eating window. Instead of eating right when you get up, you’ll wait until lunchtime to eat your first meal. And after dinner, you stop eating. In this example, you have about an 8 hour time window when you consume calories and 16 hours of fasting.
Benefits of Time-Restricted Feeding
Why do we want to stop eating for hours a day? There are lots of studies showing the benefits.
- Reduces body weight and body fat
- Improves lab markers like cholesterol and triglycerides
- Improves your body’s mechanism to digest glucose and lipids (fats!)
- Induces autophagy, which is your body’s way to clean out inefficient cells. If something isn’t working appropriately, those cells are the first to be destroyed. Autophagy helps with metabolic conditions (diabetes), neurodegenerative diseases (Alzheimer’s, Parkinson’s), cancer, and viruses.
- Decreases inflammation
And the best part is, you’re still eating the same and just as much food, you just do it in a smaller time window. This sounds amazing, right? Can we jump right in and start now? Nope, there is more to it for cycling women.
Why Some Experts Say It’s Not Good For Women
Unfortunately, medical research usually excludes women in studies. It turns out that our bodies REALLY don’t want to be hungry. And this makes sense during our fertile years. Our body wants to protect a fetus, even if we don’t want a baby right now.
Because of that, women in our fertile years are most susceptible to lack of food, which can cause a hormonal imbalance if not done correctly. The first hormone released will be ghrelin, a fast-acting hormone that will make you want to eat. As we go longer without food, we can get a disruption in luteinizing hormone (LH) and follicle-stimulating hormone (FSH). These are the hormones that surge at ovulation, and not eating enough food can cause us not to ovulate. Not having enough LH or FSH will also decrease our levels of both estrogen and progesterone. It won’t improve your ratio, but it will reduce all of the hormones that we need to regulate our cycles and our energy.
It’s not a human study, but rats ended up with reduced ovary size and irregular cycles after about 12 weeks of fasting. This result sounds scary and is why we need to make sure we try IF safely.
How To Try IF/TRF Within Your Cycle
The most important thing to remember is that not eating is a stressor. We don’t want to add more stress when we are unable to handle it. Here are some guidelines that cycling women should follow.
- If you are going to have a stressful day, avoid any form of IF!
- On days when you have intense workouts planned, you should be eating to fuel your workout, not fasting.
- I still recommend measuring your HRV each morning. When HRV levels are higher, that’s a good time to try IF. If it’s low, get up and eat breakfast.
- If you’re new to TRF, start with a 12-hour fasting window and see how you feel. You can always work your way up. Most experts recommend that women never go over a 16-hour fasting window.
- If you have any hormone disruptions, don’t try IF until you’ve fixed your hormones. Fasting is going to make it much more challenging to regulate your cycle.
Related to your cycle:
- NEVER fast during menstruation. You need to take it easy, not stress your body with fasting.
- The best time to try IF is during the follicular phase. Your body can handle stress the best, and it knows that you’re not pregnant yet. Your hormones are less likely to turn on you and try to protect a fetus.
- I don’t think fasting is a great idea during the luteal phase, especially in the last five days. These days are the PMS period, and we should be nourishing our body, not getting hangry because we’re fasting.
Intermittent fasting is likely to improve our health and energy. The problem is that as a cycling woman, we need to do it right. Reducing calories by too much, or fasting for too long can cause our body’s stress response to spike. We need to remember that most health research doesn’t put cycling women into consideration, and we can do more harm than good by jumping all in. Start small, and see how your body reacts. If you get hungry, eat! But you will probably be surprised how long you can go without food, especially during the follicular phase. I’d love to hear how this is working for you!