Menstruation: Science, medicine and mythology

24:44There's a little bit more calorie requirement. And that's in the second half of the cycle. In the second half, right. Whether that's, you know, related to sort of preparation for pregnancy, the extra tissue that's required to build, you know, all those types of things. And definitely lots of people have food cravings in the second half of their cycle in the luteal phase. And that can be really significant for some people, can be less so for others. And sometimes that's folded into kind of the whole PMS, premenstrual syndrome kind of complex or premenstrual symptoms. And definitely there seems to be a craving for carbohydrates.

25:15That seems to be kind of a pretty universal thing. And also chocolate is a pretty universal thing too. Whether that's a true biological need versus chocolate makes people feel good. You know, it's so it's kind of hard to know, you know, are people craving something because it's, you know, it's a time where they don't feel as well. And it makes me feel good when I have some, you know, so it's hard to know. But, yeah, so there is, you know, a slight increase in the calorie requirement. And definitely people have some food cravings and carbohydrates tend to be the ones that are listed most in that.

25:47And I'm not sure that, you know, we have a biological explanation. The hormone progesterone may be part of that, but I don't think we have a good answer. We had a question that came up a lot from our listeners, which is, I think, something you also touched in the book about what role, if any, does stress play in this connection between these parts of the brain and then on? Yeah, well, so stress isn't good for anything. I mean, that's kind of the blanket answer. But yeah, absolutely. So people have really tried to understand this connection between stress and the menstrual cycle. And it's a hard thing to study because people often also change their eating habits when they're stressed.

26:25People have tried to look at it, for example, in context of war, which is incredibly stressful, but there's also often calorie restriction during that time, right? So it's very hard to tease out. And people aren't keeping a food journal when they're going through an incredible stressful event. So how do you know? So what we think is it probably requires a pretty significant amount of stress to have an impact. But it wouldn't necessarily have to be like a single massive stressful event. It could also be a daily chronic stress, like a bad employer, that type of thing, or perhaps, you know, a bad, you know, home relationship.

26:59And for some people, then, that can have an effect on the menstrual cycle and can actually stop menstruation. Okay, so it's not a myth that stress can stop you having your period, stopping menstruating. Yeah, it's not a myth. But I think it's important that for a lot of women, I think, have sort of been dismissing, oh, well, you were just studying for an exam. So it's not – generally not that level of stress. It would be kind of more of a significant stressor. And if you think about – and many people are under significant stressors. Then if you think about it from an evolutionary standpoint, you know, if there's, you know, food – if you don't have enough food, if there's a massive sort of environmental catastrophe, that's probably not the best time to reproduce, right?

27:40So it kind of makes sense that there's these fail safes in there to sort of not put that massive biological investment of reproducing in a time where it may not be likely to succeed. So you can understand that there's sort of an evolutionary basis to it. But because stress can, again, have impact on calories and we know calorie restriction absolutely can shut the menstrual cycle down. So, you know, we have to kind of sort all those things out. I'd like to ask about PMS. We had a lot of questions around that. And I think you've touched a part on this, but like could you just explain a bit more like what is it?

28:14Does it involve this brain that you're describing as well? And also sort of how prevalent is it? Like how does it present always in the same way to anyone who's listening to this for themselves or someone they love? So premenstrual symptoms or premenstrual syndrome and then the more severe form, premenstrual dysphoric disorder, PMDD, are sort of a collection of symptoms that are associated with exposure to progesterone. So they can't happen in the first part of the cycle. So if people are having these symptoms before they ovulate, then it's not PMS or PMDD. It may be a different diagnosis. And so that's one of the situations where keeping sort of a menstrual calendar for two or three cycles can be useful because sometimes people can have depression, and depression can be worse with hormonal changes.

29:04And so you want to know, is it that or is it PMS, PMDD? And PMS is the collection of symptoms that might include like bloating or fatigue or headache, irritability, food cravings. Those are very common symptoms. And, you know, if you look at the broader collection of symptoms, you know, it can affect 70 to 80 % of women. Some people are more severely affected than others. If you're looking at PMDD, it's much less common, but it's much more severe. And people can have really profound depression, really profound mental health changes during the second half of their cycle. Some people can even have, you know, suicidal tendencies.

29:43And so that's, you know, obviously requires treatment. and obviously the more severe, the more, you know, the more we want to offer treatment. But so that's kind of the spectrum. The actual cause, I think that we don't quite understand. We do know that because it happens with, it has to happen after ovulation, that exposure to progesterone is clearly part of it. But there's all kinds of other chemicals, you know, in your brain that are, you know, can be affected as well. And since antidepressants can be very effective, Obviously, you know, there's, you know, involvement, obviously, of serotonin or norepinephrine or dopamine.

30:21And but I don't think we truly understand at a brain chemistry level what's going on. And just for me to understand, because you talked before about some of the pain that's going to happen while you're actually having your period. But the symptoms you're talking about here are not really related to that. Is that right? Yeah, that's correct. So people can have PMS and not really have menstrual cramps. So there's sort of this other collection of symptoms. And people can have terrible menstrual cramps and never have any food cravings. And that's part of the complexities of the experience. And this is, you know, I think a really important way.

30:55It's, again, important to have the discussions because people sometimes think they're abnormal if they have the symptoms or if they don't have the symptoms. You know, many women who have PMDD, you know, the very severe form, you know, have been written off and been told that they're crazy or told that they're too hormonal. All these awful things have been told to them. And they have a real diagnosis and a condition that has treatment. And that's terrible. That's part of the culture of shame. If you don't know that this is a medical condition and you've been dismissed by your providers, you could start to think, my gosh, am I going crazy?

31:31What is going on? Everybody's telling me there's nothing wrong with me. But there actually is. You actually have a medical condition. And Jen, how long would be, you know, again, trying to get to like the facts behind this, how long a period would like on average someone who's having these PMS symptoms experience them? Is that for like the full two weeks of the second half of the cycle or what sort of normal? It can vary. So some people might just have symptoms the last few days. Some people may have it for the full two weeks. Some people might have it for seven to 10 days. You know, I think that as, you know, gets more severe, so severity can be not just the intensity of the symptoms, but the length of the time of the symptoms.

32:09So if you think if you have pretty disabling symptoms, but you have them five days a month, or five days a cycle, you know, you have 25 days to recover in between. If you have them for 14 days, you know, then you might only have 14 days to recover in between, right? Or 12 days if you have a shorter cycle. And that doesn't mean that people who have, you know, five days of symptoms shouldn't be offered treatment. They absolutely should. But when you start to think about how then it can kind of carry over when it starts to, you know, if you're having like basically 50 % of your life affected by these symptoms, that can be pretty dramatic for people.

32:43But some people can be really affected even just for two or three days. And so that's, again, why it's important to talk about it and to be able to offer people treatment. And for people on contraception or whether it's oral or IUD, do they still experience PMS? The estrogen-containing birth control pill can be very effective at treating both PMS and PMDD. It won't take away, you know, people may still have food cravings or other types of things. And obviously it doesn't work for everybody because not all therapy is 100 % effective. but stopping ovulation, which stops that sort of cyclic release of the progesterone and the change in hormone levels.

33:20So giving people constant hormone levels seems to be an effective treatment for many, which tells us it's less about the levels and more about the change in levels that matter, the ups and downs can be very effective treatment. But with a hormonal IUD, you're still ovulating. So you're not taking away any of those triggers. So people can still have those symptoms, absolutely. And again, I want to point out that the birth control pill may not work for everybody. So someone might say, well, I'm taking it, I still have symptoms. And yeah, I mean, not every medication works for everything. Interesting.

33:51And there's also certain diseases that I know we think about when we think about menstruation. So one of these, again, I think that isn't talked about a lot is PCOS, so polycytic ovarian syndrome. But actually, it's really prevalent. I would be great if you could explain what it is, how prevalent it is, and let us understand it a little bit better. Yeah. So polycystic ovarian syndrome affects about 10 % of women. And that makes it the most common endocrine disorder among women of reproductive age. So there isn't another hormonal condition that affects 10 % in medicines, a pretty staggering amount.

34:28And it's a very medically complex thing that we should suspect when people have a regular menstruation when they have a regular ovulation and they have evidence of increased male, what we classically call male hormones, androgens. So they may have increased acne, they have increased hair growth on their chin. In severe forms, they could even have some hair loss on their head. What is this? What's going on? Basically, what is happening is during the development of the follicles. So I mentioned, and I alluded to this earlier, there's about a 300-day journey. So when you're born, you have all your follicles are dormant.

35:12They're completely asleep. And to get to the stage where they can accept the VIP ticket that we talked about, that's about a 300-day journey. And we understand very little about that. There's like all this maturing that's going on that we don't even think of, of this egg, long before it starts the journey that I learned about in school or whatever, where it sort of starts wandering down this tube. Exactly. It's not just sitting there ready, which is sort of, I think, what I got. Yeah, I think people think it's like they're asleep and then boom, they're ready for the VIP ticket. But just like going to any club, it takes your time to get ready, right?

35:43So it's a 300-day getting ready journey. I will not comment in this room on that. Oh, I get ready in five minutes. I'm sure you do, Jenny, as well. Well, I think the older you get, the less time it takes to get ready. I don't think I'm going to study that, though. So somewhere along in that development process, there is a glitch. But we don't really know, is that the trigger or is the trigger from something else? So what we're seeing is that these follicles are not quite getting to the point where they should be able to accept ovulation. They are filling with fluid. There's hormonal imbalances in the production from the follicles.

36:22Then we also have many people have insulin resistance as well associated with polycystic ovarian syndrome. And that also contributes. and there's increased inflammation as well. And so it's sort of, we don't really know the chicken or the egg here, you know, is the disturbance of ovulation the cause or the result, right? Is the insulin resistance the cause or the result? Is the inflammation the cause or the result? Or are we actually looking at a couple of different conditions that we're lumping together because they present in the same way? And so in a nutshell, that's kind of polycystic ovarian syndrome.

36:59And it's a really important thing to know about because not only does it cause irregular periods, which can obviously also affect fertility for people, but it is associated with an increased risk of metabolic syndrome and then also type 2 diabetes. It's associated with an increased risk of endometrial cancer. It's associated with an increased risk of depression and suicide. And there's many other, you know, an increased incidence of fatty liver. So there's many other serious health ramp increased risk of hypertension and cardiovascular disease. So there's all these other serious health implications of polycystic ovarian syndrome.

37:34So you should really think of it as sort of like a system-wide condition, not just sort of an ovulation problem. Yeah, it's interesting. All of the factors it's associated with are very much linked with diet. You know, high blood pressure, insulin resistance, obesity, high cholesterol, etc. that's linked with this. And so I guess it's a time that we have to be really, really mindful of the food that we're eating. Obesity is not a cause of polycystic ovarian syndrome at all. What it is is something that can make the symptoms much worse. And so when we look at all populations, the incidence of PCOS is the same, whether someone is obese or not.

38:16But people who are obese have worse symptoms. So when we look at study populations, they're overrepresented because who's more likely to come to a PCOS clinic? Somebody who has worse symptoms. Okay, interesting. And so that kind of has a bidirectional problem. So first of all, you know, if you tell people it's all related to your weight, then that's wrong. And, you know, their symptoms may be partially related to it. But that makes people, they feel dismissed. But then what happens is people who aren't obese are told they can't possibly have polycystic ovarian syndrome because they're not overweight.

38:50And so they then don't get the care that they need. So the interaction with obesity is probably related in part to the worsening of insulin resistance. That's a component of PCOS. Worsening of the inflammation, that's part of PCOS. And so many symptoms can be improved with weight loss for some people. But it's also important for people to know that there are other treatments as well and to understand that, you know, many people, losing weight is challenging. Many people have been dismissed because of fat phobia in the doctor's office. So we have to be very, very mindful of that and, you know, offer therapies independent of that.

39:33Jen, I'd love to move now for all of our listeners who've been listening to this, understanding it, switching now really to more actionable advice for them. So I guess maybe starting with PMS, where you described how many people, I think you said 70 or 80 % of women can be experiencing this. We had a lot of questions. Is there anything they can do about it? Yeah. So first of all, you know, for many people, mood symptoms can improve with exercise. Now, obviously, that's not the only thing we offer to people. And certainly, you know, if I was feeling poorly and my doctor just said, oh, well, you just need to exercise more, I would probably like have felt like very put off.

40:15So I always like to say that that's not something that should just be offered as a standalone treatment. But almost every medical condition improves with exercise. And we've seen some really recent great data on the impact of exercise on mood from a beneficial standpoint. So that's one option to think about. Certainly, when people are really suffering with PMS, there are hormonal birth control pills that take away those hormonal fluctuations. And also, antidepressants can be very effective when people are especially with the mood-based symptoms that are the worst. And the interesting thing with the antidepressants is you can just take them for the period of time that you have your symptoms.

40:55And so that doesn't mean you have to take them the whole cycle. So if you just have bad symptoms for 10 days a month, you can take them for 10 days. Okay, it's not one of these because I think often I was under the impression this is something I have to take for like months and months before it starts to have effect. No, not at all. So you can take them just so. Now, that's not always easy for people to manage. Like it's not intuitive to say, oh, I'm going to take them for just 10 days every cycle and I've got to wait. And then you think, oh, is that my PMS or am I just feeling irritable because my boss was mean to me today?

41:23Like you don't know, right? So it can be hard. So some people decide to take it every day because it's easier. Some people decide just to take it, you know, when they're ovulating, if they know. So then they've kind of covered the second half of the cycle. And other people decide to take it when they have the start of their symptoms. And so those are, you know, those are some different strategies, depending, again, on the severity of symptoms. You know, I also think it's great for people to have a, you know, a good, healthy foundational diet, but also not to beat themselves up if, you know, if they feel that having chocolate for two or three days of the month makes the month much more bearable, then great.

41:59Our data says that the dark chocolate is pretty good. So it's about switching the type of chocolate potentially rather than having to give up. I know. I was thinking that should be like, you know, part of a, you know, a government allotment that we all get our good quality chocolate every month. I love that. We'll start campaigning on that. I think that's a brilliant worldwide campaign. I think so. And Jen, what about menstrual cramps? So you said some people have them as strong as if you're actually having birth contractions. Yeah. What can we do to counterbalance that? So ibuprofen, non-steroidal anti-inflammatory drugs, naproxen, and even starting them a day before, like if you have an idea when your period is going to start.

42:38So they can be very effective at reducing menstrual cramps. I think it's important to point out that if those don't work, it could be because you have something else going on like endometriosis, which is a condition where tissue very similar to the lining of the uterus is growing outside in the pelvic cavity. But also, I think it's about 10 % of people that these drugs just don't work for them. So it's just kind of they don't help. Then all of the hormonal methods of birth control can be very effective. And so a hormonal IUD, the birth control pill, the Nexplanon implant, the Depo-Provera injection, those are all very effective ways.

43:15And they work by one, the implant, the injection, and the pills work because they stop ovulation. But also, there's a hormone in them called progestin, which is a synthetic form of progesterone. And progestin keeps the lining of the uterus very, very thin. So when there's less lining to come out, there tends to also be less cramping. And you can take these medications every single day so you don't even get a period. So that's also an advantage. Yeah. And it's interesting because the hot topics amongst many of my friends who are in their late 40s is either menopause or thinking about their children who are having quite extreme symptoms, some of them.

43:55And something I know they would be desperate for me to ask you while you're talking about this is, is it safe from a young age for someone who's 14, 15, 16 to go on to some of these contraceptive pills in order to alleviate these symptoms, these kind of cramps? Yeah. So we do think it is safe. And I think that unfortunately, hormonal contraception gets a very bad rap on social media because fear sells. And if you think about the risk to you medically of having untreated painful periods. So people just think about, oh, well, you're missing school. But we know that people who have very severe period pain are more likely to develop other pain conditions in their life.

44:42And that we think that early exposure to severe pain can prime the nervous system in a way to actually heighten the pain experience, meaning it makes you more likely to develop other pain conditions. So could we be setting somebody up for more likely getting migraines later in life? Could we be setting them up for other medical conditions by undertreating their pain? Never mind if they have to miss two days of school a cycle, then that could affect their academic performance, which could affect getting into the university they want to go, could affect their job performance, could affect their career.

45:14So it's really important for people to think about this, not just as, well, it hurts, but which is important itself to treat because people deserve to have their pain treated. But what are the ramifications of untreated pain, right? So then you think about it from that standpoint that the birth control pill, the IUD, the Nexplan, they would all be a net positive. And so, yeah, so we think that they're very safe to be on. There is some conflicting data on the risk of depression related to starting hormonal contraception. And the data is very conflicting. And there are some studies that show that there could be an association for some people and some studies that show that it isn't.

45:59If we say maybe it could be, if we err on that side of caution, then the incidence of depression associated with the pill for teenagers might be one in 200. But that's not certain. It absolutely could be less than that. And I think one of the problems with the data is, so people start the birth control pill because of something. They don't just like, I'm totally fine and I don't have a new partner and I'm just gonna go on the pill because. So teens can be in domestic violence situations, right? So starting the pill, that could be part of that. They could be in a relationship that's having an impact.

46:37They could be starting the pill because they have PMS, which is associated with mood disturbances. And maybe they actually have depression and not PMS and it's been misdiagnosed. So they're not getting their depression treated. But polycystic ovarian syndrome, which is a reason many people go on the pill, is associated with a higher risk of depression and suicide. So it's very difficult to study. It's an active area of research. But I think that people always have to look at the reason you're going on. And there is a massive impact of untreated pain. And, you know, the idea then, so then what are we supposed to do?

47:10Just let kids curl up in the corner? And, like, you know, that's not a solution. Jen we're we're running short of time but I do want to pick up on this comment that you talked about earlier about the iron deficiency because you described something like 40 percent of girls under 22 which sounds huge it is and I've also I've got Sarah as well so both of you here I really want to make sure we follow up that sounds like very actionable advice like what what can you do about this yeah so if you are someone who menstruates and you have symptoms like fatigue brain fog hair loss you just don't feel right, and you get a period.

47:47So if you're somebody who hasn't had a period for five years because you've gone on a hormonal IUD, then you could have iron deficiency for another reason. But most of the younger ones are related to menstrual. You need to not just get a blood count to check for anemia. You need to also get a ferritin level. Because a ferritin is a reflection of the iron stores in their body. Because you don't want to be brushed off. You can have a normal blood count and not have anemia and still have severe iron deficiency. I diagnose that maybe every single day in my practice because iron deficiencies associated with a lot of other symptoms.

48:22So I'm often testing people because of those other symptoms. And the number of women that I identify every week, you know, who have iron deficiency is pretty staggering, which fits with the data that we see. And so I think people need to get their ferritin level checked. And if their ferritin level is low, they shouldn't accept that that's normal, that that's okay. It needs treatment. And if oral iron's not working, then there's intravenous iron, which is actually really very safe intravenous iron now. And also, the reason for the iron deficiency needs to be investigated. So someone needs to ask you about your periods and if you're soaking pads, all these things, because there's treatment for heavy periods as well.

49:06And investigations may need to happen too. You talked about oral supplements of iron. And there's some fascinating research coming out now to show the benefits of if you are taking iron supplements of having them every other day. There's a particular chemical increases when you have an iron supplement that actually prevents you absorbing too much of the iron. Because, again, our body's really clever mechanisms to make sure we don't iron overload. and so actually if you can miss out a day means that you'll then absorb it you know 48 hours later yet if you're having it every day this particular chemical that stops the absorption is at its peak and then blocks the absorption i'd like to try and do a quick summary which we always do it was quite complicated so please correct me where i got uh any of this um this wrong so we started talking about why do people menstruate at all i hadn't realized we're in this very small group of animals on this earth that do this.

50:03So something quite special. And you're explaining that we have this cycle that is really about preparing sort of the lining of our uterus in order to deal with this obviously particularly difficult human fetus compared to all the other fetuses that are out there. And so we build this line, which I think called was a decidua. And once you do that, it's a sort of, it's a one-way ticket. So you create this and having done it, it's like, well, if you aren't going to get pregnant, then our bodies kick off this system and says, we've got to get rid of it. It peels off. And actually what's happening is the bleeding is when this peels off, which makes sense, like sort of ripping something off your skin.

50:36And so it's normal blood that's coming out. And there's this process that's sort of pushing this decidua and the blood out before you start the cycle again. You then said, look, there's a lot of myths around this and things that you shouldn't accept. So if you're having heavy bleeding that isn't normal, you should be going and seeing your doctor. It can lead to iron deficiency. I think you said 40 % of women under 22 are iron deficient in the US, which is a huge number, no doubt partly affected by the diets they're all eating as well. You then went on and said like lots of pain is also not something to just accept.

51:07And again, something you should go and speak to your doctor about because there are things that you can do. We then talked a bit about sort of the differences in the cycle, about how it affects how you're feeling and some of the symptoms you have and that particularly the second half of the cycle is what's associated with all of these experiences. So you can be hungrier. You know, that's true. You can have these food cravings, especially for sort of carbs and chocolate. Yes, stress can impact that, but you're describing like, it's not like the stress of doing an exam. It's got to be at a really high level of stress.

51:38Then we talked about PMS, premenstrual syndrome, and you said 70 to 80 % of people who are menstruating experiences. So it's a huge number of people. Again, it's in the second cycle and the duration varies. What could you do about it? So you said, interestingly, you started with exercise. So that is real. It's not made up. Birth control pill can have a really big impact. And we had a conversation about whether it was safe even for adolescents. And I think, Jen, you're saying, yes, I think it's safe. And actually, you know, in many cases, a good solution because these impacts are all very serious.

52:14An antidepressant can actually help while having symptoms. And a healthy diet can also be having an impact. We sort of finished off talking about iron deficiency and what could you do? And I think, Jen, you said like literally every day in clinic, you're diagnosing somebody with iron deficiency. This is not sort of a really rare occurrence. It sounds like there are a very large number of people who may be listening to this podcast with that. And in terms of supplementation, interestingly, popping every day is not as good as every other day, which I think is very counterintuitive. And then in some cases, if this isn't working, you may actually have to go to having something intravenous.

52:49Did I manage to capture that okay? Yeah, yeah. I think that's a really great summary. Jen, thank you so much for coming in and taking us through this little summary of what came out of the book. And I know we will have many follow-on questions. I hope we might be able to get you to come and join us again in the future. Oh, I'd love to. I'd love to. This is great. Thank you so much for having me. No, I have learned so much. So thank you. Thank you. It's a pleasure. Thank you very much. I hope you learned something today and enjoyed the episode. If you listen to the show regularly, you probably already believe that you can transform your health by changing what you eat.

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