Why Eating Enough Fat Matters for Hormones and the Menstrual Cycle | Ep. 606

Episode 606

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and six.
If you’ve been a long -time listener to the podcast, I’m sure you’ve heard me talk
about the importance of eating fat, the importance of balancing macronutrients. We
need sufficient protein fat and carbohydrates in order to make hormones, in order to
have a healthy menstrual cycle. But in today’s episode, we are diving to a really
interesting study that provides a more specific insight as to why we actually need
to consume sufficient fat if we’re really looking to optimize our hormones and
maintain a healthy menstrual cycle. So without further ado, let’s go ahead and jump into today’s study.
Like I always say, the title of these studies leaves something to be desired. So I
will read a portion of the title for the study, but if you’re wanting to take a
look at the abström,
reasons, which we’ll get into. But I think what you should know about this study is
that they were not trying to improve menstrual cycle health.
They were not trying to show the importance of fat for hormone production.
This study was actually designed to try to figure out if putting women on a low
fat diet might reduce their risk of cancer because of the hypothesis that estrogen
causes cancer to grow. And so if we find a way to suppress estrogen production,
then we might actually reduce cancer risk. And so again, think about what I just
said. So the researchers actually within the design itself of the study specifically
were trying to reduce hormone production. And the way that
controlled trial for a two -month period or even sometimes like a two -week period or
something like that. Sometimes the intervention is quite short. But in this particular
study, the intervention period was two years. So they actually had a control group
and they had their test group. And their test group, they showed them and gave them
information about reducing fat in their diet and essentially had these women in the
test group, they were reducing their fat for a two -year period and they followed
the participants during that period, which is really interesting. In order to achieve
the reduced fat intake in the intervention group or in the test group,
the participants were encouraged to reduce their dietary fat intake to 15 % of their
total energy intake, which is pretty significant. That’s a very small amount.
And to put that into perspective, the study results after the two years, the test
group, on average, was consuming about 34 % of their total dietary intake of fat.
And the test group, although they significantly reduced their fat intake was around
20 % of their total energy intake. So it’s kind of hard to reduce fat intake that
drastically. And the kind of normal tendency of the control group was to be right
around 30 -ish percent, which is interesting. So again, a couple of things. I’m
always looking at how they measure the hormones and how they measure the cycle.
And so essentially what the researchers did was they tested hormone levels before
their fat, obviously, intake. And so the test group’s fat intake was significantly
lower than the control group. So they saw about a 20 % drop in estradiol,
and they saw about a 33 % drop in progesterone at the two -year mark.
And so if anything, this study shows us that fat intake is heavily related with
our, you know, hormone output. If we think about how our bodies make hormones,
well, our hormones estrogen, progesterone, testosterone, cortisol, even vitamin D are
synthesized from cholesterol. And so it stands to reason that fat intake plays a
significant role. And in real food for fertility, in our hypothalamic amenorrhea
chapter, we cite a significant amount of really interesting research about H .A.
women. So in this study, we’re not talking about women who have undernourished or
under exercise to the point that they’re losing their cycle. But interestingly, women
who are trying to reduce their intake of calories and things like that will often
specifically try to exclude fat. And one of the differences between women who have
full -blown H .A. or on the H .A. spectrum is that at times they’re significantly
reducing their fat. In fact, there was one study that we talked
menstrual cycles, they weren’t tracking them in any way. So the only thing that they
did is at the end of the two years, they asked the women to identify the first
day of their last period. And so they really weren’t tracking the cycle lengths to
kind of see if there was any changes or any disruptions in the menstrual cycle
whatsoever. That was not their intention. And also, they didn’t track cancer rates.
So even though they were trying to determine if this intervention would have an
impact in cancer rates, they didn’t actually track that. So that was not one of the
parameters that they tracked. So they actually weren’t able to draw any conclusions,
whether or not this diet actually made a difference for the stated goal. Instead,
they were kind of able to say, okay, well, when we reduce the fat, the estrogen
reduced, and therefore there could be a benefit. And that was kind of how they
concluded. So, I mean, what can we take from this study? I think there’s a few
things. One of the things I think to mention is that when you’re trying to find
data, see on.
us about the overall picture. So it doesn’t mean we can draw a direct conclusion
and say, this is exactly what causes it. But it’s really interesting to see how
consuming a low fat diet impacted hormone production. And also that, of course,
the researchers kind of knew and expected that that would do it. So that’s something
to think about as well. So when we’re looking at what would be the optimal diet
for a woman who is actively trying to balance her hormones, actively trying to
reduce negative hormone symptoms, things like PMS, or if she’s trying to conceive and
she’s trying to optimize ovulation and support optimal follicular development. So going
a little bit into the physiology of the menstrual cycle, if we’re looking at how
the menstrual cycle is correlated with hormone production, then what we’d have to
understand is that we produce estrogen as our ovarian follicles develop as we move
towards ovulation. And so if we’re seeing a 20 % drop in estrogen,
that typically means that follicular growth in development is less than optimal. And
one of the ways that can be tested would be through ultrasound. You can actually
test the size, measure the size of the ovarian follicle. And there is an ideal size
of an ovarian follicle that would indicate optimal development and growth in that pre
-ovulatory phase. And so when we’re seeing a significant drop in estrogen levels,
it does provide that indication that follicular development is being affected. And the
follicle that, once it’s fully developed, that’s the follicle that ovulate at
ovulation. And once you ovulated ovulation, that follicle then turns into the corpus
luteum, which then produces progesterone for the rest of the cycle.
that there was a 33 % drop in progesterone as well. And so there’s a study that I
referred to before, again, that I covered in real food for fertility, I believe. And
in that study, it wasn’t specifically fat. The study that I’m thinking of, the
researchers were actually reducing overall caloric intake. So they had a control group
of women who were eating enough overall. So they had a group of women who they
were
significantly less fat, shows us what happens and so reliably that this was the
researcher’s whole plan. They were like, how do we reduce estrogen? Well, we just
make these women eat less fat. And then that’s exactly what’s going to happen. So
definitely something to consider about and certainly shows us how important fat intake
is in just overall hormone balance and supporting optimal, healthy menstrual cycles.
Registration is officially open for our next round,
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And so this certainly doesn’t mean that we need to go overboard. And one thing to
consider as well was the control group naturally consumed an average of about 34 %
fat. So without really any intervention, they were consuming the amount of fat that
they needed to. This group received specific instructions. They were having check -ins
on a regular basis in between the two -year period. They weren’t tracking all of the
data in the two -year period, but they were taking dietary data throughout for the
participants and encouraging them and giving them instructions for how to reduce their
fat intake. So certainly this was an intentional process here to have this group to
reduce their fat intake. And again, just so interesting to think about how that
affected overall hormone production. If you’re wanting an even deeper dive into the
research as to why fat is important, if you’re wanting to kind of understand more
of the logistical side of the role that fat plays in supporting hormone production.
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