Health News: Stress increases ghrelin levels

Do you ever feel like you need to grab something to eat when you’re stressed? Well, there’s a hormone for that! It’s called ghrelin and new research shows that ghrelin levels increase when you’re under stress.

Ghrelin, the hunger hormone, is now known to be part of our biological response to stress! This very recent study reviewed 10 other studies and confirmed that when people are put into a stressful situation (like a timed math test) their ghrelin levels quickly shoot up. That makes us want to seek food and start eating. The good news is that we now know that levels of this hunger hormone start going down soon after the stress is gone even if we don’t eat anything.

But, this stress-ghrelin response is not the same for everyone.

Listen in (or read the transcript below) to get the scoop on this new review study that links stress to hunger.

Listen (and subscribe) to the rEATsearch podcast

Resources and links (notes for episode 19 on ghrelin levels )

• REVIEW STUDY: Bouillon-Minois, J. B., Trousselard, M., Thivel, D., Gordon, B. A., Schmidt, J., Moustafa, F., Oris, C., & Dutheil, F. (2021). Ghrelin as a Biomarker of Stress: A Systematic Review and Meta-Analysis. Nutrients, 13(3), 784. https://doi.org/10.3390/nu13030784
  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7997253/
• HOW TO DETERMINE STRENGTH OF STUDIES INFOGRAPHIC by Compound Chem Rough guide to types of scientific evidence: https://www.compoundchem.com/2015/04/09/scientific-evidence/
• *FREE* DONE-FOR-YOU MINI ARTICLE FOR HEALTH PROS ON THIS STUDY SO YOU CAN SHARE IT WITH YOUR EMAIL SUBSCRIBERS OR SOCIAL MEDIA FOLLOWERS: https://leesaklich.com/wp-content/uploads/2021/09/DFY-health-scoop-00-FREE-SAMPLE-FOR-SALES-PAGE.docx

Nutrition and health pros: Want a free mini-article to share this study on ghrelin levels with your email subscribers?

Click the button below to download a free sample of a Health scoop (new study update) based on this exact study:

Transcript for episode 19 on ghrelin levels (lightly edited)

[00:00:28.370] – Leesa

So I’ll dive in then.

[00:00:30.350] – Lindsay

All right. Welcome back to REATsearch.

[00:00:33.770] – Leesa

Welcome.

[00:00:34.430] – Lindsay

Season two.

[00:00:35.690] – Leesa

Season two. I know we’re here. We made it. So this is awesome. We’re going to talk about a study. We’re going to briefly talk about a fascinating study, that I thought was fascinating, and it’s all about stress. I found this study when I was researching to write an article on stress, and it was really interesting. This was just published earlier this year. I believe it was February or March. I think it was March 2021.

[00:01:03.330] – Lindsay

Oh, that’s really recent then.

[00:01:05.270] – Leesa

Yeah, it’s really recent. And it was fascinating to me because, in general when we hear about stress, we talk about stress hormones, for example, what do we automatically think about?

[00:01:18.650] – Lindsay

Cortisol?

[00:01:19.490] – Leesa

Cortisol. We think about adrenaline. We think about the hypothalamic-pituitary axis. We think about these things that are well, well known. But, of course, there’s always more to know. And that’s why research keeps going. This particular study was really interesting because it actually was a review of multiple studies—of ten—which makes it a higher quality study than a single one. And it was a review and a meta-analysis of ten studies.

[00:01:47.090] – Lindsay

Awesome. Her favourite.

[00:01:49.010] – Leesa

I know. I love these! They have so much more robust information in it, especially if the studies they find are good quality studies. What happened was they found that ghrelin was a stress hormone. [Ghrelin levels increase when you’re under stress.]

[00:02:02.270] – Lindsay

This amazes me when you kind of stop and think about it, it makes sense. But until you’re shown that I was like, what? So to be clear, I really don’t know much about this article, but I did get a sneak peek. So I’m going to be amazed along with our listeners as I hear about this article. But okay, I need to hear more.

[00:02:26.930] – Leesa

Yeah, it’s totally interesting. It’s called “Ghrelin as a Biomarker of Stress Systematic Review of Meta-Analysis,” and it was published in the journal Nutrients earlier this year.

[00:02:38.550] – Lindsay

Awesome. And, of course, full link online in our show notes.

[00:02:42.930] – Leesa

And the link will be there. The reference is there. You can read it all yourself. So I want to pull out a few of the cool highlights for this. So stress, of course, is your fight-flight-freeze reactions. And it’s like —I don’t know about you—you can sometimes feel the hormones going through your body. It’s like all of a sudden you get hot.

[00:03:04.830] – Lindsay

Yeah.

[00:03:04.830] – Leesa

Right. And there are so many symptoms of stress. And one symptom that we may relate to is: “I need to grab something to eat man, I’m stressed.”

[00:03:17.010] – Lindsay

Yeah.

[00:03:17.010] – Leesa

“I need to just find a snack.” You know what I mean? Do you find that?

[00:03:21.750] – Lindsay

When it’s chronic stress? Yes. Short-term stress, I’m okay. Long-term stress, yeah. Actually, it’s funny. You say that a few years ago, my husband and I did the EdgeWalk at the CN Tower.

[00:03:36.330] – Leesa

No way. How was that?

[00:03:37.770] – Lindsay

It was fantastic. Let me tell you, I’m scared of heights. And so I did it because I was like, I need to face this fear of mine.

[00:03:47.010] – Leesa

Good for you.

[00:03:48.030] – Lindsay

And afterwards, I was so hungry. We went out for lunch after, because we had done it late morning.

[00:03:55.590] – Leesa

Right.

[00:03:55.590] – Lindsay

I inhaled a lot of food, and it was because of that. I know it was because of that stress response. That was pretty extreme, though.

[00:04:03.630] – Leesa

Yes. Walking along the edge of the CN Tower is pretty extreme.

[00:04:08.010] – Lindsay

1200 feet up, no less. And they make you lean out over the side.

[00:04:12.030] – Leesa

What?

[00:04:12.570] – Lindsay

Oh, yeah. No, it was “adrenaline worthy,” let me say.

[00:04:17.370] – Leesa

Right. That is really interesting. I’ve never done it. Would you recommend it?

[00:04:22.650] – Lindsay

I would. Yeah.

[00:04:23.463] – Leesa

Okay.

[00:04:23.850] – Lindsay

It was definitely a very good experience. Overall, I felt it was crazy, but it was good to be able to say I could do it and definitely worth it. It was a really good experience.

[00:04:38.350] – Leesa

Right.

[00:04:38.350] – Lindsay

I felt very safe, considering you’re hanging out over 1200 ft of nothing.

[00:04:42.550] – Leesa

Okay. Right, of course, you’re all harnessed in, etc.

[00:04:45.190] – Lindsay

Overly, so. Yeah, I couldn’t sit. I was so harnessed in.

[00:04:48.130] – Leesa

Standing room only! Got to stand on the edge of the CN Tower!

[00:04:52.610] – Lindsay

Yeah, pretty much.

[00:04:55.430] – Leesa

Awesome. So, ghrelin, just for background, because we’re chatting about this hormone called ghrelin. It is a hunger hormone. It has many roles in the body. This is the main one that we’ve been discovering and researching, but it’s an appetite regulation hormone, and it’s made by the stomach. It’s also made elsewhere. But we’ll focus on the hunger and the stomach right now, and it gets you to start looking for food.

[00:05:26.150] – Leesa

It starts this “food-seeking” behaviour and “meal initiation” behaviour. And these studies that were reviewed in this particular article showed that ghrelin levels increase in response to—and this one looked at—acute stress. So I think we talked about this in another episode. What does ghrelin remind you of?

[00:05:50.390] – Lindsay

Gremlins.

[00:05:51.230] – Leesa

Gremlins!

[00:05:53.270] – Lindsay

It’s different for you.

[00:05:53.270] – Leesa

For me, ghrelin reminds me of the grumbling, like the stomach grumbling. It’s so funny. That’s how you remember from now on, any of our listeners are going to know ghrelin is the grumbling gremlins hunger hormone. Okay.

[00:06:06.290] – Lindsay

Yeah.

[00:06:07.310] – Leesa

So again, this looked at multiple studies. They have to induce stress somehow in people and measure the before and the after. Right. That’s an experimental clinical study. In some of these ten studies, they had people immerse their hand in freezing cold water; their non-dominant hand, for two minutes and they would measure the ghrelin levels.

[00:06:29.750] – Lindsay

Okay.

[00:06:30.350] – Leesa

Others, they would have to do a timed math test. Right, so there are a number of ways that they induce stress. People get stressed out with the stuff.

[00:06:41.630] – Lindsay

No, I just find it funny that what they’re using as a stress inducer is a math test.

[00:06:51.390] – Leesa

A timed one. Exactly.

[00:06:51.390] – Lindsay

Okay. That makes sense. It definitely stresses a lot of people out.

[00:06:54.690] – Leesa

Legit. This is a legit stressor. And they measured the levels of ghrelin. And what they found was it increased quite a bit within the first five minutes.

[00:07:05.370] – Leesa

Right, It’s like you’re exposed to a stressor and your ghrelin levels increase, and then it slowly decreases over the next minutes and hours. So, for example, you relieve the stress. So your hand comes out of the water, you’ve done the test, or whatever. And it has a half-life of about less than half an hour. So within half an hour, it’s half of what it originally was. And then within another half an hour, it’s another half. So within an hour, it’s about a quarter of what it was at the beginning. And so it slowly goes down. But it shoots right up in the first few minutes and then it slowly goes down.

[00:07:41.130] – Leesa

So, the thinking is that stress can cause people to feel like they need to eat. Let’s see what the actual implications are if there’s a hormonal link on it. So these ten studies show that there is a hormonal link. Now they wanted to take this a step further because this is really interesting to me. This is really cool stuff. So to take it a step further, they wanted to look at overweight. Part of the hypothesis is having excess weight causes stress. And having stress can be a contributor to excess weight. So it’s like this loop. And so they’re like, “Well, how do we determine if ghrelin is part of that as well?” And so what they did was people who were experiencing overweight and obesity. They had higher ghrelin levels than people who were not experiencing overweight and obesity. And the higher the BMI of the person, the longer the ghrelin stayed up.

[00:08:53.830] – Lindsay

So the half-life was extended. So it lasted longer once it was actually in the blood.

[00:08:58.750] – Leesa

Peak was extended.

[00:08:59.770] – Lindsay

Oh, wow.

[00:09:00.910] – Leesa

So instead of peaking for five minutes, it was peaking for even up to 45 minutes.

[00:09:06.010] – Lindsay

That’s a long time.

[00:09:07.690] – Leesa

So ghrelin levels were higher for longer before it even started decreasing. So, wow, there are other hormonal links that we’re just discovering now when it comes to stress, which is a huge problem, especially pandemic stress on top of the other stresses, right? And excess weight is a problem for a lot of people. And so hormones interconnecting those is one of possibly quite a few different issues.

[00:09:50.050] – Leesa

The other thing, too, is when it came to the weight and the ghrelin levels, we really don’t know what comes first, right? Because as we’re seeing that kind of vicious cycle, where having excess weight and experiencing that causes stress, and having stress is linked to increasing weight. So we don’t really know what comes first. But this study did show that when it comes to acute stress—short-term immediate stress—ghrelin levels shoot up and stay up for a while before it actually starts coming down. That could be a big reason or definitely contribute to why you feel like, “I’m stressed. I just need to grab something to eat.”

[00:10:31.150] – Lindsay

Yeah, definitely. We see this with a lot of other parallels in health and nutrition. What came first? Did the arthritis come first, which caused people to experience overweight? Or did people with overweight limit themselves and then they started developing more inflammation? What came first? The chicken or the egg. And those are just two examples.

[00:10:51.670] – Lindsay

But you have to break the cycle somehow and disrupt some of these feedback loops so that you can start addressing the issue.

[00:11:03.430] – Leesa

And the more we know, the more we can address and have things that are actually going to work because they’re based on research that is finding out these additional things to consider that we may not have even noticed or realized in the past.

[00:11:20.650] – Leesa

Oh, you know another interesting thing the study said? We used to think that ghrelin levels came down after eating, right? Because if it initiates your food-seeking/meal initiation behaviour, that after eating is when it comes down. But in these experiments, they found that it started coming down, even when the people were not eating.

[00:11:44.230] – Lindsay

That I find really interesting. I think our understanding in the field was that what’s going to bring it down is somehow satiating with food. It’s interesting,

[00:12:15.670] – Lindsay

We know with cortisol as well—I don’t know what the half-life is—but it doesn’t last a long time otherwise you’d stay in this heightened state for extended periods of time. It peaks and then it slowly tapers off. I’m wondering how similar those curves are.

[00:12:32.350] – Leesa

Yeah, I don’t know.

[00:12:33.970] – Lindsay

Or if there’s an inverse relationship with leptin? Because I know with people that struggle with obesity as well or weight issues or even appetite issues, there tends to be dysfunction as well in leptin. I wonder what the overlap is with some of the leptin dysfunction as well.

[00:12:53.710] – Leesa

And remind everyone what leptin is.

[00:12:55.810] – Lindsay

Leptin is that satiety hormone. My understanding is that when we’re hungry, we have ghrelin levels increase.

[00:13:04.270] – Leesa

Yes.

[00:13:04.270] – Lindsay

And then as we eat . . . well, used to be as we eat.

[00:13:09.370] – Leesa

And likely for many people, it’s not a guarantee.

[00:13:12.910] – Lindsay

Yeah, that comes down. And at the same time, we slowly have an increase in leptin, which is the hormone that signals “I’m full. We have all the nutrients we need. We can stop eating now.” But my understanding is that when people start having issues with obesity and even insulin sensitivity, there tends to be an overlap with leptin sensitivity. We lose that sensitivity and so it takes more and more hormone to be able to get that signal coming through. Which is why people often have a hard time stopping their eating early enough because they’re not getting that signal to their brain because we have some type of leptin resistance. Would you say that you have understood in the same way?

[00:13:56.710] – Leesa

Yeah. I think that there’s still a lot more to learn because I think that a lot of the fundamental research on stress has still really been focusing on the cortisol-adrenaline response and knowing ghrelin and leptin, which kind of work is opposites to each other: ghrelin makes you want to find food and leptin makes you feel full. Right? I think that there’s still a lot to learn about how those hormones work, which is why I think this is so fascinating.

[00:14:27.850] – Lindsay

Yeah. I didn’t really realize. It makes sense. I didn’t really think of it as like a food-seeking hormone, but I guess it signals hunger, which is when you start rooting through your cupboards and fridge like: “I need something.”

[00:14:43.030] – Leesa

Right, they call it, I believe, it was “food-seeking behaviour” and “meal initiation.”

[00:14:50.830] – Lindsay

That’s funny.

[00:14:51.730] – Leesa

That’s how they describe ghrelin in this study.

[00:14:54.190] – Lindsay

Yeah. I think it’s awesome when something that we thought we fully understood, or at least understood well, we start learning it’s way more complex than we initially realized. And there are more behavioural implications to what we thought was a simple hormone. I’m just kind of amazed at how cool hormones are because they just do so much. They really are the master controllers. And I think there’s so much more to them than what we understand right now.

[00:15:29.630] – Leesa

Yeah. I think there’s a lot to learn in this area for sure. To me, I hadn’t even heard about those other ten studies being done historically, because obviously they were done. Ghrelin was discovered in 1996, so it’s been researched for quite some time now; 25 years.

[00:15:50.150] – Lindsay

Wait! 96 was 25 years ago already. I thought it was like five years ago! That problem with that time lapse.

[00:15:59.510] – Leesa

Yeah.

[00:16:00.410] – Lindsay

We keep thinking like the 80s was ten years ago. Hold on a sec, that was 40 years ago? Yeah. That’s really interesting. They’re so cool and so much more complicated than what we originally thought. So really. I mean, let’s talk take-home message, then. Stress induces ghrelin levels, which induces appetite, which, in some, can last for quite a while. And so really, if we want to try and get hunger under control, one of the many ways we can approach it is by learning how to manage stress a little bit better. Is that what you would say?

[00:16:48.090] – Leesa

Yes. Manage stress, for sure definitely is a huge contributor to so many issues with chronic diseases and problems. I definitely would say that stress management is a huge thing. And also, I think that just knowing that the feeling—if you’re not truly hungry—the feeling of “I need to eat something right now,” when you’re stressed can pass without eating. If you’re not hungry. I mean, if you’re hungry, eat, eat food when you’re hungry. This is not the point here at all. But if you’re not hungry and you’re like, “oh, my gosh, I’m really stressed now. I really just want to find something.” It can in some cases and for some people pass without grabbing a snack.

[00:17:41.430] – Lindsay

I think it is making sure you’re aware of that connection between something that happened that induced stress, and it will be different for everybody.

[00:17:51.390] – Leesa

Yes.

[00:17:51.390] – Lindsay

And now I’m craving something probably not very good for you. Yeah, mine changes depending on what’s going on, what I have available.

[00:18:03.010] – Leesa

Chocolate covered almonds for me!

[00:18:04.690] – Lindsay

Typically I like sweet stuff, for sure. Sweet and greasy, which is, again, really not a good idea. But being aware of that connection so that you can see your behaviour or at least your urges for what they are, which is just a physiological response. And that if you can wait it out, go for a walk, call a friend, do a puzzle, find some way to distract yourself while that ghrelin levels come down.

[00:18:33.910] – Leesa

I think that the whole concept of managing stress is really the fundamental million dollar question.

[00:18:43.030] – Lindsay

All we have to do is manage stress.

[00:18:45.550] – Leesa

Right? ExAcTlY!

[00:18:46.450] – Lindsay

That’s a mountain on its own.

[00:18:47.950] – Leesa

I get it, totally. It’s totally crazy to think that there’s one simple solution, which they’re 100 percent isn’t. But just understanding more about those interconnections between things that may have seemed to be interconnected. And now it’s like, oh no, there’s experimental clinical evidence showing it literally is interconnected.

[00:19:08.830] – Lindsay

But I think it’s interesting, too. If you can start paying attention to what your triggers are, what do you know, induces stress? This is one of those stress management techniques, like are you able to avoid it at all? For so many, it could be finances. And this is why I think I love learning about personal finance. I find it so interesting. But one of the things you can do is set up an emergency fund. Because now you know you have a safety net if something happens, if the car breaks down, if you need to fly home to visit a loved one. God, life can happen in so many different ways. You now know it’s like, “Okay, I know this isn’t going to have to go on the credit card, and I’m going to go owe tons and tons of money.” So, there’s one example where you can plan ahead so that you are reducing the likelihood of having this extreme stress response. And this is just one example. There are so many different ways. If you know certain people are your trigger because they do certain things. And let’s face it, this world is pretty trigger happy right now. Avoid your triggers. I’ve gotten off of a lot of social media lately. Because of that because I just was getting so worked up about some of the things some people were saying. So I’m just removing myself from that equation and it’s helping.

[00:20:28.630] – Leesa

That is so true. Those are really great stress management strategies. I’ll add one that I like that is super hard for me, and that is saying no.

[00:20:40.150] – Lindsay

Yeah. Oh, my gosh. Yeah.

[00:20:45.050] – Leesa

Saying no. I found some templates on how to say no in the most loving, kind, supportive way. But really, taking on so many things, be they clients, be they household responsibilities, whatever. All of these things pile up, pile up, pile up that sometimes, you know, “If I take on something else now, this is just not cool.” So I think that saying no in a very respectable way is a skill I wish I had years ago.

[00:21:24.590] – Lindsay

Well, and I think it’s funny you bring that up, too, because I think I’ve seen the same list and one of them said you don’t have to explain why. It is nobody’s business . . .

[00:21:34.310] – Leesa

Right.

[00:21:34.310] – Lindsay

What is going on in your life, and they don’t have to know every intricate detail of why you cannot take on this other thing. All you have to do is say politely, “I’m sorry it doesn’t work for me right now. I’m going to have to decline.” And that is something everybody has the right to say, for sure. Again, we’re avoiding setting ourselves up for stressful situations.

[00:22:00.530] – Leesa

Right.

[00:22:00.530] – Lindsay

That’s a big factor. If we know certain things are going to trigger us, the best thing we can do is just avoid it overall.

[00:22:06.950] – Lindsay

I think I’ve talked about this before: my sugar addiction. I have a huge sweet tooth. My body does not like sugar, though . . . like it does, but it doesn’t because it just makes me feel horrible after. And I’m one of those people, if I have even a little bit, I lose all control and I can’t stop eating it. And I find if I just avoid it altogether, then I do much better. And I find from when I talk to people, people fall into one of two camps. They can either be like moderators where they can just have a little bit, and then they kind of get their fill. And other people are in my boat where it’s all or nothing. Learning your own behaviours and what systems work for you because it’s all so personalized. It’s so individual and so unique to each one of us. And we just have to learn about ourselves so that we can figure out the best actions for ourselves.

[00:23:01.950] – Leesa

Right. Keeping our own self-care and health top of mind is a good skill.

[00:23:10.050] – Lindsay

This is really cool. I’m so glad that you shared this article because it’s such a valuable piece of information for how individuals can help themselves and how health professionals can help their clients in making healthier choices.

[00:23:26.010] – Leesa

Right. Just knowing sometimes is kind of the first step, right?

[00:23:30.090] – Lindsay

That’s half the battle. Anybody who’s in my age bracket will know what I mean: GI Joe.

[00:23:39.750] – Leesa

Oh okay.

[00:23:39.750] – Lindsay

No, you don’t remember that? Oh, my goodness.

[00:23:43.050] – Leesa

Were they public service announcements? I think.

[00:23:46.350] – Lindsay

No, I thought it was GI Joe. “Knowing is half the battle.” I have to call my brothers and ask because they would probably know.

[00:23:52.350] – Leesa

Yeah. So hopefully this is helpful because there are always new studies coming out and we learn a little bit more every time. So putting more and more pieces of the puzzle together will help us move toward the latest research and the best approaches moving forward.

[00:24:13.650] – Lindsay

Yeah. Continuous learning. The best!

[00:24:15.630] – Leesa

Yes. Definitely. All right.

[00:24:18.150] – Lindsay

Awesome. Thank you so much for sharing.

[00:24:20.670] – Leesa

Yes. Thank you.

[00:24:21.990] – Lindsay

Well, if you enjoyed this episode or this podcast, please rate and subscribe and review us on whatever platform you’re on. This is how we are able to become more accessible to other listeners so that we can help more people.

[00:24:38.490] – Leesa

And feel free to follow us. We are most active on Twitter [@rEATsearch], rather than any other social network. We also have an email address, so it’s reatsearchll [at] gmail.com, so feel free to reach out if you have a specific recommendation, a specific study that you’re looking at and let us know. Alright. Thanks so much. Have an awesome day.

[00:24:59.730] – Lindsay

Thanks. You too.

I am text block. Click edit button to change this text. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.