Diving into two studies that discuss time of day and meal size and it's affect on metabolic outcomes and ovulation. We also discuss the take aways from intermittent fasting and keto style eating patterns.
Caitlin Johnson (00:00) Welcome to the PCOS Answers Podcast with Caitlin Johnson, your functional medicine dietitian. This podcast is a private podcast only available through the PCOS app. It will provide practical sciencscience-basedebased answers to all of your PCOS questions, and every episode will leave you with something you can do today to help your PCOS. I'm so glad you're here. Welcome to another episode. Caitlin Johnson (00:25) We are here today to do part two of considering Keto, intermittent fasting, and breakfast and how that might affect ovulation. So in the last episode, in episode nine, we talked a little bit about why Keto and intermittent fasting are proposed in this PCOS population, their impact on insulin resistance, and a few things from each of those methods that are worth extracting and applying in our PCOS lives. But if you can remember one of the take home points. While keto and intermittent fasting have benefits in lowering insulin resistance, so increasing insulin sensitivity, lowering the amount of insulin that you make, which can then lower the amount of testosterone that you make, which can then improve your overall PCOS symptoms, potentially improving ovulation, potentially improving egg quality in all these different areas. Caitlin Johnson (01:25) Even though these diets can do this, one of the most compelling reasons to not jump into one of these diets is that you don't have to be that strict or extreme to enjoy the benefits of improving insulin resistance. So that's the take home message from the last episode that I want to jump start this episode with. So this question is kind of the next logical question to me. Does the time that you eat your meals affect ovulation? Does the time that you eat your meals affect insulin resistance? Caitlin Johnson (01:59) It's such a great question. So I'm glad you asked, or maybe I proposed it, but we're going to dig into it. Breakfast definitely impacts ovulation. So when you eat a good portion of your calories at the beginning of your day, it can actually help you ovulate. So when you eat a large portion of food towards the beginning of your day, even in the middle of your day, you still have many active hours where you're doing things. Caitlin Johnson (02:29) You're changing laundry, you're walking to your car from work, you're going into the grocery store, maybe you're hitting the gym where your body is active and moving and can utilize the energy that you're taking in. When we bulk a lot of our intake towards the end of the day, we don't have that same kind of metabolic activity that metabolic output for our body to soak in the sugar and use it. So if you eat a larger portion of your calories towards the front end of your day, it can actually help with insulin resistance. And we've seen in multiple studies that it can actually impact ovulation. So let's look at a couple specific studies and see how this eating structure in the day can impact insulin and ovulation. Caitlin Johnson (03:23) So in the first study that we're going to look at. It was a study done for twelve weeks with participants put into a breakfast group and participants put into a dinner group. The breakfast group ate their biggest meal at breakfast. Why? We called it the breakfast group. Caitlin Johnson (03:40) And that meal was almost 1000 calories, which I'm sure you're hearing this and you're going like, that's what somebody told me to eat in my entire day. Okay? They're eating a very large breakfast. Lunch was about 650 calories and dinner was about 200 calories. I'm rounding. Caitlin Johnson (03:57) It was 980 at breakfast, about 640 at lunch, and about 190 at dinner time. So a big breakfast, a moderate size lunch, a small dinner. Now the dinner group had exactly the opposite. They started their day with a small breakfast, about 190 calories. The same size lunch, about 640 calories. Caitlin Johnson (04:19) And then their largest meal of the day was dinner. 980 calories. So here's the interesting part, guys. The meal size matters. The breakfast group saw improvements in insulin resistance and they also saw improvements in testosterone levels, meaning testosterone levels went down. Caitlin Johnson (04:37) They also saw more improvement in ovulation. The breakfast had a decrease that was significant under the total area of a glucose curve. So when you think about that, we're just looking at kind of like a bell curve, that curve went down by about 7%. Not huge, but the total area under the insulin curve decreased by 54%. So 54% less insulin in a 24 hours period. Caitlin Johnson (05:04) Floating around your body, you can see how that would then trickle down to lower testosterone levels and improving ovulation. That's huge. It means that the insulin levels were really impacted by eating the largest meal of the day at breakfast. Caitlin Johnson (05:22) The breakfast group also saw lower levels of free testosterone. Now pay attention to this. This is really important. Free testosterone went down by 50%. Free testosterone is something that we want lower. Caitlin Johnson (05:35) This is the testosterone that isn't bound to another protein so it can bounce off cells and do its dirty work. Can go to your ovary, install ovulation. It can go to your chin and make your hair more coarse and beard like. It can go to the hair on the top of your head and tell it, hey, fall out. This is the testosterone we really want to decrease. Caitlin Johnson (05:55) The breakfast group. The people that just ate a bigger breakfast saw a decrease in free testosterone by 50%. That's a huge deal. The sex hormone binding globulin. This is the thing that goes around and grabs onto the free testosterone and other male hormones androgens, and turns it off. Caitlin Johnson (06:13) This increased by 105%. So if the number at the beginning of the study was in like the 30s, it went up above 61. That's huge. This is kind of like the helper, the Mrs. Pacman that floats around and starts eating up all the free testosterone. Caitlin Johnson (06:29) So meal timing and size of meal actually matters. Both groups saw ovulation rates increase in the second month of the trial. But the third month of the trial, the breakfast group had about 50% of their participants ovulating. That is crazy. The other thing that's interesting about this study, if you read it, is it wasn't like these meals were incredibly balanced. Caitlin Johnson (06:55) So if you were to just extract some helpful keys from this, if you're not used to eating a larger breakfast, starting to implement eating breakfast at all, or starting to increase your breakfast even just a little bit, and what if that breakfast was pretty well balanced? Imagine what we could see with your free testosterone, your ovulation. Now why does eating a larger breakfast and a smaller dinner impact insulin and ovulation? Again, I'm very glad that you asked this question. When you eat the largest meal of the day in the morning, you have that bodily activity to manage the increases in blood sugar. Caitlin Johnson (07:33) It's also something that has to do with our circadian rhythm and how our body kind of rests and recuperates overnight. Having more kind of empty your stomach during that time allows your body to do that work better. Your normal activity during the day is higher than the overnight period. So eating a bigger breakfast, a moderate sized lunch, and getting most of your fuel from those meals has an impact on your overall insulin output. Ending the day with a really large meal sends large pulses of insulin into your body right before you're about to lay down and snooze an insulin. Caitlin Johnson (08:12) Second job is to tell cells if there's extra energy stores fat. So not only are we impacting symptoms free testosterone, ovulation, having your largest meal of the day be dinner is something that can actually impact weight and hormone signaling. What can we glean from this? We don't need to eat 1000 calorie breakfast and only 200 calories at the end of the day. But could you eat your largest meal of the day at breakfast or lunch and make dinner the smallest meal of your day? Caitlin Johnson (08:42) This really flies at modern culture, at least in the United States, where the biggest meal of the day is typically at the end of the day. And a lot of us find ourselves starving ourselves either at breakfast or at lunchtime because we're too busy and we can't really stop to eat or we haven't planned and prepped or brought along what we really need. And then dinner is kind of normal and then we binge in the evening time and edd. So adjusting and shifting and creating safety in your day and allowing your body to have more fuel in the morning and early afternoon will allow your body to use that energy and be able to improve insulin and allow your body a better rest period overnight and likely improved sleep quality. Now that study that I told you about was done in a PCOS group of women that were of normal BMI. Caitlin Johnson (09:38) This is typically what people call lean PCOS. Personally, I hate this term, so we will describe it as those that had a normal BMI. What happens if we look at a group that has an overweight or obese level BMI, but still we're looking at a PCOS population? A very similar group of scientists took a very similar study design and said, okay, we want to be able to tell if eating a bigger breakfast and smaller dinner produces the same metabolic benefits in overweight or obese women with PCOS. Can it lower insulin? Caitlin Johnson (10:18) Can it lower fasting glucose? Can it lower Homa IR scores? Now, the one major difference in this study design is that they put obese and overweight women into a calorie deficit. So this was a calorie intake that should have yielded weight loss, but the groups essentially ate the same amount of calories. Okay, so both groups ate a total of 1400 calories daily. Caitlin Johnson (10:47) In the breakfast group, again, this is the group that eats the bigger breakfast. Breakfast was about 700 calories, lunch was about 500 and dinner was about 200. Then the dinner group that switched breakfast was the smallest meal of the day at 200 calories. Lunch was 500 calories and dinner 700 calories. In both groups, we saw weight loss. Caitlin Johnson (11:08) Okay, we restricted calories. That makes sense. We expect to see some level of weight loss. Although the fasting glucose, the insulin and a hunger hormone called grelin were also reduced in both fasting glucose insulin and Homa IR reduced, they went down to a greater degree in the breakfast group. So we saw metabolic improvement in fasting glucose insulin and taking those numbers and calculating the Homa IR index, we saw that the breakfast group saw more improvement. Caitlin Johnson (11:45) Improvement was seen with calorie restriction and weight loss. But there were other differences in the groups. The breakfast group's triglycerides went down by 33.6%, so the triglycerides went down by a third. In the dinner group, the triglycerides went up by 14.6%. So again, we see that timing of meals when you have your largest meal of the day impacts metabolic outcomes that you wouldn't necessarily expect to see. Caitlin Johnson (12:16) Why would eating just a little bit of a bigger dinner have higher levels of triglycerides? So their triglycerides actually went up, and having a larger breakfast and a smaller dinner, we saw triglycerides go down by almost 34%. So both groups completed an oral glucose tolerance test to test the insulin levels. After this twelve week study was over. And the group that ate the bigger breakfast had a greater decrease in glucose and insulin. Caitlin Johnson (12:42) The group also lowered the hunger hormone ghrelin and their hunger scores. They were more satisfied after their meals. So when we talk about improving insulin resistance and we're talking about trying to improve some of the behaviors that help us succeed at either weight loss or balancing our plate or not feeling really victim to our hunger cues, lowering grelin the hunger hormone, improving Satav and improving food cravings is actually really important. And we saw that to a much greater degree in the group that ate the larger breakfast. So eating a larger breakfast, whether you're in a calorie deficit or not, whether you need to lose weight or not, and decreasing your evening amount of calories, can improve insulin resistance. Caitlin Johnson (13:33) We also see in other studies, independent of calorie restriction, that breakfast eaters are more likely to ovulate. So when I think about these kind of fad diets, and I think particularly about intermittent fasting, most people that intermittent fast skip breakfast. Sometimes they kind of, quote unquote, break the rules. They have coffee, but they put MCT oil in it. There's no carbohydrate or really any protein. Caitlin Johnson (14:02) And so we're not necessarily spiking your blood sugar and creating an insulin response there. But having that much caffeine on an empty stomach can spike cortisol. So there are other hormones that are involved here. Cortisol is that stress, chronic stress hormone that your adrenals also make. As your adrenals make more cortisol, your body makes more of an androgen a hormone from your adrenals as well called Dhgas. Caitlin Johnson (14:33) And its entire job is to protect your brain from cortisol. So when you start your day without eating and then you add onto that burden of expecting a lot out of your body without a lot of fuel using caffeine, and we speed up your heart rate, we are not surprised to see higher levels of cortisol. I would expect that I am then not surprised when I see higher levels of DHEA-S, which also impact hair loss, acne, hearsitism anovulation egg quality, the list goes on. So the idea of completely skipping breakfast does not equate to quality health with PCOS. Do I think having a sufficient overnight fast can be incredibly helpful for your PCOS? Caitlin Johnson (15:27) Yes, absolutely. Do I also think you should eat breakfast? Yes, absolutely. Now, if you're not somebody that's used to eating breakfast right now, you're going to say to me I don't wake up hungry, then I'm going to say to you, then let's not start at breakfast tonight. I want your dinner to be half the portion that's normal and go to bed quickly. Caitlin Johnson (15:49) Tomorrow morning you'll wake up hungry, I promise. And if you do wake up and you still feel like I just can't think about eating, grab a handful of nuts, have a hard boiled egg and a piece of fruit, you can start small. You don't have to go from eating no breakfast to eating 1000 calorie breakfast tomorrow. That's not what I'm saying. I'm saying let's create a sufficient overnight fast, gain the benefits of an overnight fast and what that can do for our insulin resistance. Caitlin Johnson (16:20) See if over time we can stretch to a full twelve hour, maybe even 13 or 14 hours overnight fast, but still have a quality breakfast, and then have a quality sized lunch. And then dinner can be something a little bit smaller, a vegetable with some really nice lean protein next to it. A small portion of carbs would be very sufficient dinner. And if you train your body that it's used to eating more amounts in the morning, then it won't be shocked or surprised when dinner rolls around and you don't need as much to eat. So we can take and pull from different fad diets eating patterns, see what the science actually says and take the best of those things and leave the rest. Caitlin Johnson (17:10) Okay? We don't need to be strict. We don't need to be restrictive. We don't need to cut out entire, not even food groups. But macronutrients, you don't need to go completely carb free to manage your PCOS. Caitlin Johnson (17:24) Now the other kind of side effect to eating more earlier in the day is you're less likely to be grabbing for those snacky foods that just are I don't even want to say the bad word in my head that I'm thinking about. They're just a void of nutrients. Okay, I'm going to say it. They're kind of crap food. They're not really food. Caitlin Johnson (17:44) Do they give you calories? Yes. Do they give you nutrients? No. And I see this huge fear of people. Caitlin Johnson (17:51) I'm afraid to eat an orange because the carbs, we deprive ourselves of the way nature package carbohydrates with fiber and vitamins and all these other wonderful things that we need. And after that we get hungry for carbs. At the end of the day, we're stressed we didn't eat enough and then we dive headfirst into chips and salsa or spicy Doritos or cheetos or popcorn or whatever it is for you. So stop being afraid of carbs. Eat enough protein at meals. Caitlin Johnson (18:23) Extend your overnight fast. If you can eat a bigger breakfast and eat real food as much as you can, lots of different colors of fruits and vegetables, and I promise you, I promise you, you will see more balanced energy levels. You will feel more satisfied. It won't happen overnight, but it will happen as you start employing these different principles. So I hope this helps you, especially in this early season of 2023. Caitlin Johnson (18:52) And we're thinking about different decisions or resolutions or ways that we're going to impact our health in this new year. We have such a quote unquote, clean slate. Let's not go extreme. Let's pick one thing to implement this week. Is that going to bed 30 minutes earlier and not having a snack right before bed and waking up and eating a little bit bigger of a breakfast. Caitlin Johnson (19:17) What if you eat right now, two eggs, a piece of toast and some avocado on that toast? Well, maybe tomorrow you could eat two eggs and two egg whites with that same piece of toast and avocado. What if you're used to having a smoothie as you run out the door and tomorrow you make a smoothie and have two hard boiled eggs on the side? How can we slowly increase your breakfast so that you're not as hungry at the end of the day and you can extend your overnight fast and what will that do for you? So my ask of you today is to hop in the community section of this PCOS app and ask a question. Caitlin Johnson (19:57) What did this spark in your head? What questions do you have? What are you thinking about committing to in this next year? Let's discuss these things together and create discourse and support one another as we transition into a wonderful, wonderful new year together, where we're going to have so much support, so much education, so much joy, so much hope, and we're going to do it together.