EP.322/ dairy and endo: Does it affect hormones?
Okay so today we’re continuing with our series on dairy and endo, and today we’re taking about hormones.
And I’m going to warn you up front - the research is mixed, and it really comes down to your personal response to dairy. That being said, non-organic dairy can be treated with extra hormones, which may influence our own, so it goes without saying that organic is preferable when possible. Of course, don’t worry about the one offs like an ice cream out or some cream on your dessert in a restaurant, but if you’re regularly eating dairy at home, organic would be a better choice.
However, organic dairy still contains naturally occurring hormones and growth factors, including insulin-like growth factor 1 (IGF-1). These growth factors, along with components such as whey protein and carbohydrates (lactose and galactose), naturally found in dairy products (with levels varying depending on the type of dairy), can raise insulin levels and IGF-1 in the body.
Insulin is a hormone that helps regulate blood sugar levels by taking glucose and delivering it to our cells for energy, or putting it away into storage, so that our blood sugar levels don’t keep getting excessively high when we eat. The effects of dairy on insulin and IGF-1 can be complex and variable. For example, IGF-1 can promote muscle growth, which may help improve blood sugar regulation by enhancing glucose uptake into muscle cells (basically meaning that the muscles use the glucose for energy). However, if dairy consumption consistently raises insulin levels, frequent exposure may lead to reduced insulin sensitivity in our cells - which means insulin comes knocking at our cells’ door, but they don’t answer, which causes blood sugar levels to keep rising. This means that over time, the body requires more insulin to control blood sugar, which can eventually contribute to insulin resistance and may increase the risk of type 2 diabetes.
Now, the caveat to this is that research does indicate that fermented dairy is associated with a lower risk of type 2 diabetes and that the fermentation process actually reduces the insulin raising effects we see with other types of dairy, and also blunts blood sugar spikes. And it’s worth also noting that the research on whether dairy can lead to reduced insulin sensitivity is very mixed still, so this may not be an issue for all of us - but for those of us with blood sugar issues already, we may want to be mindful of how we personally respond to dairy.
Now, this isn’t our only consideration with dairy and insulin. When insulin levels get high, especially repeatedly over time, it can actually affect our sex hormones and ovarian function. High insulin levels can raise levels of androgen hormones, like testosterone. Testosterone can cause ovulation to be delayed, become sporadic or not happen entirely, so raising levels can trigger cyclical changes, such as longer or shorter cycles. Additionally, IGF-1 can also raise androgens. In fact, research has shown that an increased intake of dairy was associated with acne, due to its androgenic effects, which overstimulate our sebaceous glands. For those of you with PCOS who are trying to keep androgens down, or who suffer with acne, a symptom of PCOS for some, avoiding or reducing dairy may help with acne, but for PCOS itself, the research is conflicted - with some research suggesting benefits for PCOS (especially yogurt) and others showing an association between dairy and PCOS risk. So again, it’s individual at this point, until we have more understanding.
However, it’s worth mentioning that there is also research showing that dairy can lower testosterone, and raise sex hormone binding globulin, which binds to testosterone and essentially renders it useless. In someone who has PCOS or elevated androgens, this could be helpful, but in someone with normal or already low levels, lowering levels of testosterone further could cause issues like pelvic pain, reduced sex drive, low energy and low moods.
The impact of dairy on oestrogen and progesterone varies. In some studies, it was shown that dairy could increase oestrogen levels and even progesterone levels, especially dairy from pregnant cows, which is common in commercially available milk products. However, frustratingly, this study looked at men, women and children but they did not measure the hormone levels of the women, only the men and children. This study showed raised levels of oestrogen in both men and children, but no ovulatory changes in women, possibly suggesting if hormone levels were impacted, it wasn’t enough to affect ovulation. The study theorised that commercially available dairy from pregnant cows could be partially responsible for early puberty which we are seeing occur in young girls. I think for those of us with endo and oestrogenic symptoms and conditions, like heavy bleeding, clots, tender breasts, etc. it’s worth us considering whether dairy could be having an affect on our oestrogen levels, if we’re consuming it regularly. That doesn’t mean that you need to cut it out entirely, but experimenting with the amounts and seeing whether symptoms improve, might be helpful for you.
However, in contrast, a study specifically focused on women, found that as dairy intake increased, oestrogen and testosterone levels slightly decreased but that this didn’t impact ovulation or cycle length. The study also showed that consuming more high fat dairy and dairy in general, increased luteinising hormone across the entire cycle. Luteinising hormone is responsible for stimulating testosterone production in the ovaries and also triggering ovulation, but it should only be high right before ovulation, and having elevated levels across the cycle, can cause sporadic or skipped ovulation (this is a classic hormonal pattern we see in PCOS).
Interestingly, the study did show a greater risk of anovulation (missed ovulation) with an increased intake of cream or yoghurt, and this was also demonstrated with low fat yoghurt in another large study previously.
The researchers are not yet clear why this occurred, though there are theories behind it, one of them being that the processing of the fats in cream and yoghurt, that many manufacturers do to improve texture, could affect levels of fatty acids that may impact ovulation. This could be especially true in the case of low fat yoghurt, which is usually heavily processed to alter taste and texture on removal of fat. I think it would also be reasonable to assume, that if LH levels were rising, that this could also influence ovulation - the question is, why with cream and yoghurt only, not the other forms of dairy?
Now before you throw your yoghurt out, the research acknowledged that previous studies demonstrates inconsistency in findings. For example, the same study that showed an increase in anovulation with low fat yoghurt, also showed that low-fat dairy was linked to a higher risk of anovulatory infertility and that there was a lower risk of anovulatory infertility with high fat diary. The researchers found that women who consumed 2 or more servings of low-fat dairy per day had a higher risk of anovulatory infertility compared to women who consumed 1 or fewer servings of low-fat dairy per week. And with the full fat dairy, women who consumed 1 or more servings of high-fat dairy per day had a lower risk of anovulatory infertility compared to those who consumed 1 or fewer servings per week. And just so you know - anovulatory infertility means that someone is struggling to get pregnant because they’re not ovulating.
So, as you can see, we don’t exactly know how dairy influences hormones, some studies show it to be protective to ovulation, and others, show it could interfere with ovulation. What is clear is most of the research indicates that dairy does seem to have some impact on hormones, which warrants further investigation.
So does this mean you should cut out dairy entirely? There are absolutely health benefits to dairy, which we’ll get to in this series and we’ve already started to cover that today, such as diabetes prevention and ovulation support with certain types of dairy. For many, it also brings a lot of people pleasure or may be a common part of their cultural cuisines, so I don’t want to say throw it out entirely - especially if you don’t need to.
But if you’re someone who has PCOS, acne, or often experiences menstrual irregularities, it may be helpful to try the elimination approach where you remove dairy entirely for one month, and the reintroduce each dairy type one by one, to observe symptoms. Typically this would be done with one dairy type per week, so for example, sheep’s diary week one, cow’s dairy week two and so on. However, when it comes to observing your cycles, you may need to be a bit more detail orientated - you might need to see how you do with just yoghurt during one cycle and see how that affects you, and compare what happens when you drink milk regularly, or cheese.
Alternatively, you could just reduce your intake to see if it makes a difference. I don’t mean you have to reduce significantly, but if you have yoghurt daily, see what happens if you have it four times a week vs. seven, and so on.
If you don’t have acne, PCOS or irregular cycles, this level of detail is probably not necessary. If you have heavy periods or pain, we’ll get to that and what to do in terms of dairy then, and if you have gut problems with dairy, go to my previous episode in this series.
Personally, some of you know that I reintroduced dairy last year after seriously breaking my ribs. I’ve been told previously that I have weak bones, and this reinforced that concern for me. And whilst the research doesn’t suggest we need dairy for bones and calcium intake, after years of being vegan, I decided to start introducing dairy to provide some bioavailable calcium sources, alongside more plant-based sources. I did experience shorter cycles with more milk, but not with yoghurt or cheese - originally. However, more recently, I have experienced shorter cycles with only consuming yoghurt, but this was after having covid, prior to that, they seemed okay, so it’s very difficult to judge. I even tested not having dairy before ovulation and only afterwards, and whilst my period came on time, I did note that my PMS was significantly worse, which I attributed to alterations in my hormones due to the dairy. Without testing my hormone levels, I can never be 100% sure. At this stage, I am confident that regular and high milk consumption, and daily dairy consumption doesn’t seem to agree with my cycle, but some fermented dairy like yoghurt or cheese a few times a week seems to be okay.
So like everything with endo, you have to work out what’s right for you. If you want some guidance on trying to identify if dairy is affecting your hormones for the better or the worse, I currently having one more space available for one to one coaching. If this is of interest to you, you can reach out on hello@thisendolife.com
Organic dairy
https://www.ams.usda.gov/sites/default/files/media/Dairy - Guidelines.pdf - regulations for organic dairy
Insulin/blood sugar/IGF-1
https://pmc.ncbi.nlm.nih.gov/articles/PMC4524299/
https://www.levels.com/blog/what-we-know-about-dairy-and-blood-sugar]
https://pmc.ncbi.nlm.nih.gov/articles/PMC4325471/
PCOS
https://pmc.ncbi.nlm.nih.gov/articles/PMC7696580/#:~:text=Yoghurt appears to be a,of hepatic gluconeogenesis [54].
https://pmc.ncbi.nlm.nih.gov/articles/PMC4085920/#:~:text=Conclusions:,consumption and risk of PCOS.
https://pmc.ncbi.nlm.nih.gov/articles/PMC5265695/
Hormones and dairy
https://pmc.ncbi.nlm.nih.gov/articles/PMC4119548/#:~:text=(Table 1).-,The prevalence of anovulatory cycles varied from 3.4% to 18.6,%, data not shown).
https://pmc.ncbi.nlm.nih.gov/articles/PMC5265695/
https://pubmed.ncbi.nlm.nih.gov/17329264/
https://pubmed.ncbi.nlm.nih.gov/19496976/
I am now taking applications for my final one to one coaching cohort of 2024
Apply here: https://www.theendobellycoach.com/coaching
Free resources:
This podcast!
Email me: hello@theendobellycoach.com
Ways to work with me:
This EndoLife, It Starts with Breakfast digital cookbook
Masterclasses in endo nutrition, surgery prep and recovery and pain relief
Live and Thrive with Endo: The Foundations DIY course
One to one coaching info and application
This episode is sponsored by BeYou Cramp Relief Patches. Soothe period cramps the natural way with these 100% natural and discreet menthol and eucalyptus oil stick on patches. Click here to find out more and to shop: https://beyouonline.co.uk/pages/how-it-works
Produced by Chris Robson