Not everyone, but. Women tend to be more sensitive compared to men when it comes to intermittent fasting. So I'm slightly cautious to advise it. I know that some women do it and it doesn't affect their cycle, and I think the reason this is, is because in the feeding window they're ensuring that they're getting in enough calories and enough nutrients. The male body has always been the default body in clinical medicine, making the assumption that women are just smaller versions of men. This could not be more wrong,’ Dr Wallace says. CNN asked Meta about the reports that it is continuing to remove, restrict, and shadow-ban female reproductive health content. CNN also asked Meta why all female reproductive health, including menstrual health, is classified as an 18+ issue.

Jonathan Wolf: that's really interesting and showing it tied to, not just generically that this is good for you. Cause it seems like the evidence for exercise in general is really compelling, but particularly towards these symptoms you might have in this first week. Hazel Wallace: Yeah, absolutely. It'll begin just before the period begins because the hormones have already dropped and you know, an anti-inflammatory Mediterranean style diet is good all cycle round, but maybe at that time you wanna load up on the leafy greens. You wanna get in more berries. You want to really make sure that you're supporting your health during that time. And because they have small funds, they'd be like, well, we just can't even do that. And so there's this sort of, ridiculous situation where so many of these studies have only been carried out on men and equally well, no one's really looked at what seems like, you know, obviously incredibly important, which is if you're seeing this big change during the cycle, presumably the sorts of, you know, the way you might think about medical treatment or even drugs would presumably want to change during this period. Categorizing reproductive health as an R-rated topic is an issue that extends far beyond Meta advertising policies, reflecting wider societal views, from politics to sex education curriculums. Imagine a world where we are teaching young girls and women from puberty - this is what to expect, this is normal, this is not normal, this is when to ask for help. We would feel a lot more empowered,” Wallace stated.

Jonathan Wolf: Oh, it sounds fascinating to try and understand more. Now, before I let you disappear, I have to follow up on the intermittent fasting. What can it do? Dr Hazel Wallace is the founder of The Food Medic, a medical doctor, registered associate nutritionist and personal trainer.

Jonathan Wolf: This is sort of particularly in the first week from the point when you have your period that's when this inflammation level is highest. Because you talked about this very inflammatory phase at the beginning. I think I know where you're gonna tell me, which is this is really under researched. But do we, do we understand how that might be changing through the cycle? Jonathan Wolf: And that's a lot of people you're talking about. So if you're saying 20, 40% of all women, women are slightly more than half the population and you're in this period of your life for what, like half your life or something like, that's an enormous number of people.Jonathan Wolf: Okay. And finally, you're, you're allowed to more than a yes or no. Now, what's the most unexpected thing you discovered about the menstrual cycle through your research?

Hazel Wallace: So it's beneficial for a cardiovascular fitness and also in the high hormone phase in the menstrual cycle when estrogen is high, just before ovulation. We do see that as well. There may be some benefits to cardiovascular fitness, for example, for endurance sports.Hazel Wallace: Sleep is really interesting and I would definitely love more research in this, especially when it comes to sleep architecture. So when we're talking about the different stages of sleep, but as a brief overview, we do see a lot of sleep disturbance just after ovulation and in that premenstrual period. So just before the next period. Jonathan Wolf: It's really interesting. I was just thinking about the phases of the moon as you talk about this. Cause I know there's always been this like sort of ancient link somehow to the moon cycle and presumably our ancestors couldn't have had any. Idea about what was going on with our hormones. But it's interesting you're describing something which is really not like just switching on and off, but something which is really phasing in and out in quite a complex like interplay here. Historically, female bodies (both animal and human) have been excluded from medical research for three main reasons: Hazel Wallace: That regular activity can actually reduce menstrual symptoms and also how heavier period is amazing. Yeah, and you know, this was, this is evidence from the Cochrane review where we pool lots of research together and we look at.

Hazel Wallace: No, but I think it highlights how severe and debilitating this condition can be for women. Jonathan Wolf: and this being the ZOE podcast, I have to ask you about the microbiome, but I think I know what you're gonna say. Do we have any understanding about whether the microbiome is actually fluctuating during this cycle as a result of all of these massive changes? Jonathan Wolf: Are there any other things that you, maybe there's not quite as much evidence, but you would guess you might be able to, to swap in instead? But there's also LH and F S H, and there's some higher up hormones as well from the brain. These hormones fluctuate across the month, the very start of the month, the first half of the cycle, we call the follicular phase, and the second half we call the luteal phase. And then we've got ovulation sandwiched in between. So if we think about nutrition, First and foremost, I mentioned in the beginning that menstruation is an inflammatory response, so our body is in huge inflammation because it's going through a big process. There's a lot of shedding going down, and we need to support that as best we can, which we can.How the menstrual cycle affects what you eat. We'll even find out if there's scientific evidence behind cycle syncing. I learned a lot and I believe you will too.