Intermittent fasting is a powerful tool to improve women’s health. Most women start with intermittent fasting to address weight loss and stick to it long-term because it makes them feel better – physically and mentally.
If you have questions about how to get started, join our intermittent fasting community for women only. There, you get all the support you need!
Many women start intermittent fasting because they want to lose weight. But intermittent fasting has so much more to offer. It brings hormones into balance that caused the weight gain in the first place.
This has many health benefits - losing weight is just a “side-effect”.
The benefits of intermittent fasting include:
All these effects are beneficial for women - and also for men. But intermittent fasting also offers some benefits that are especially relevant for women. All benefits are not related to the weight scale.
Calorie-restricted diets can harm women’s fertility – at least in the short-term. The female body reacts to food scarcity, and it's crucial that the body is well nourished before pregnancy. It’s even more important during pregnancy – a lack of nutrients can harm the health and development of the unborn baby.
If a woman is not in good health, her body may “decide” that it is not a good time to bear a child. A calorie-restricted diet can simulate such a scenario – bringing consequences such as irregular periods and trouble getting pregnant.
Reduced caloric intake – especially fasting – is seen as a threat to female fertility.
What’s worse than eating nothing at all?
But there are misconceptions about intermittent fasting. You can still eat every day when you practice intermittent fasting. You don’t even have to eat less overall. You just change when you eat.
Conversely, obesity is strongly associated with infertility. Women with a BMI > 25 often struggle to get pregnant (6). Obesity is often caused by an underlying insulin resistance (7).
When women lose weight (and hence insulin resistance improves), their ability to conceive improves. Insulin resistance is the real threat to female fertility.
Before talking about insulin resistance, you might want to know more about the role of intermittent fasting in the women libido.
You probably know insulin as a blood sugar-lowering hormone. Insulin resistance means that cells stop responding to insulin. Because high blood sugar is harmful, the pancreas has to produce more insulin to force blood sugar (glucose) into the cells. For this reason, people with insulin resistance have very high insulin levels – even in between meals.
However, insulin not only lowers blood sugar, it is also a fat-storing hormone (8). You may have guessed – high levels of a fat-storing hormone make it hard to lose stored body fat. This is the reason why insulin resistance causes weight gain.
People with type 2 diabetes have very high insulin resistance, and many struggle with obesity. Coming back to the link between insulin resistance and infertility: Polycystic Ovary Syndrome (PCOS) is a hormonal disorder that affects many women in their childbearing years. Up to one-quarter of women between the age of 15 and 44 have PCOS. PCOS interferes with ovulation, the menstrual cycle and is a common cause of infertility.
Insulin resistance is seen as the underlying cause of PCOS. Because intermittent fasting is such a powerful tool for improving insulin resistance, it can also treat PCOS and, hence, increase fertility (9).
Not surprisingly, as rates of insulin resistance and diabetes increase, the rates of gestational diabetes (diabetes during pregnancy) rise as well.
Gestational diabetes puts the baby’s health at risk. While the mother’s diabetes normally remits after childbirth, women with gestational diabetes are at high risk for developing permanent diabetes (10).
Because intermittent fasting improves insulin resistance, it reduces the risk of developing diabetes during pregnancy (11). While intermittent fasting is not recommended during pregnancy (unless prescribed by your GP), women can practice it before getting pregnant to reduce the risk of gestational diabetes.
Hormones have a strong impact on female wellbeing. Hormonal changes throughout the menstrual cycle can cause mood swings. When entering menopause, hormones show their real power over mental wellbeing.
You may think that sweets can improve your mood and soothe mental disturbances. Well, quite the opposite is true. Yes, the brain needs sugar, but the problem is that sweets raise blood sugar levels only for a short time.
A blood sugar crash soon follows, which has the opposite effect on your wellbeing. Low blood sugar can cause weakness and even panic attacks without a snack within reach. However, by having another snack, the cycle starts over again – this leads to an unstable blood sugar level (and mood) several times per day.
But during a time when your hormones go crazy, you need the opposite: stability.
Intermittent fasting provides this stability. Once glucose storage runs low, the body starts to access fat storage. The liver then turns fat into ketones.
Ketones can cross the blood-barrier and are an excellent source of energy for the brain (12). Because the body has plenty of stored fat, ketones are also a very reliable and stable energy source. When fasting, there’s an unlimited supply of ketones.
The good news: The brain loves ketones! Good-bye brain fog – hello mental clarity. Many people experience a fasting high when abstaining from food – ketones are the reason.
When your brain is optimally supplied with energy, your mood also improves. Sugar cravings that cause mood swings and make you cranky fade.
Intermittent fasting is currently being studied as a treatment for depression, and the results look very promising (13, 14)!
Losing weight through calorie-restricted diets is often accompanied by a loss in muscle mass. This can be prevented by strength training such as weight lifting, but this is not an option for many women.
The risk of losing valuable muscle mass increases with age. Hormonal changes during menopause promote muscle loss. And also, the risk of osteoporosis increases as the bones get weaker.
Intermittent fasting, however, is known to preserve muscles:
A study of women over 60 showed that the muscle-retaining effects even apply to women of advanced age: After 6 weeks of 16/8 intermittent fasting, the women had lost 2 kg of body weight. This was mainly fat mass as the muscle mass did not change significantly (17).
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