Hunger Hormones
Ever felt like you just can’t stop eating? Your stomach feels like it might rupture any moment, but you’re still driven to keep eating more and more? Or is it the opposite, you haven’t eaten much but are already so frustratingly full? Why is that?
As usual, the answer might be hormones.
Hormones are a bitch. Anyone who went through puberty knows that and those who have hormonal issues know that even more. The absence of a single hormone (looks at my thyroid in anger) can fuck you up.
So, what hormones regulate our appetite? Where do they come from? What happens if they don’t work properly?
The hypothalamus is a region of our brain that’s, among other things, responsible to control our appetite. A part of it can be reached by certain proteins and peptides, despite the blood-brain barrier. One of those peptides is …
Neuropeptide Y (NPY) is another great example for how weird biologists are when naming stuff. Either it’s totally absurd (like the “sonic hedgehog gene”) or extremely boring (like the green fluorescent protein). @suesa
Anyway,*** NPY stimulates the appetite***, which leads to a greater food intake. There are hormones that inhibit it (leptin and insulin) and those that stimulate it (glucocorticoids, which is an awful name to write down, and ghrelin).
Interesting enough, mice that were bred to not have any NPY showed normal behavior. The only special thing the researchers noticed in the study where they had a look at NPY deficient mice was that it’s beneficial if the mice also don’t have any leptin.
And what is leptin?
Did you know that your fatty tissue can produce hormones? Now you know. One of those hormones is leptin. With that in mind, it’s not surprising that the amount of leptin that’s produced in the body rises with increasing body fat mass, is it?
In contrary to most other hormones that control appetite, the leptin levels aren’t connected to when and how much you eat. Instead, it seems to be tied to your internal clock: It’s high when you sleep and lower around noon and in the afternoon. This leads (or at least it should) to you not feeling as much hunger at a time when you’re supposed to be asleep.
And if leptin is missing? You get obese and your immune system develops issues. Luckily, those symptoms can be held in check by giving the patient some leptin. It’s similar to insulin in that way.
Insulin … yeah, that has something to do with appetite too!
You all (hopefully) know that insulin plays an important level in diabetes. Either not enough insulin is produced (Diabetes 1) or the body is resistant to it (Diabetes 2). The second one is usually acquired through an unhealthy lifestyle.
Insulin leads to the absorption of sugar by certain cells (those that require insulin to absorb sugar) from the blood. Naturally, this means insulin spikes after a meal. The message that reaches your brain is “alright, we have enough food, please stop eating!”. And less hungry you become until the insulin levels drop again.
Fun fact: Your brain only notices the change in blood sugar levels, not the actual level. That’s one reason why you can still eat the dessert after finishing a meal that made you full. The sugar in your blood is gone and your brain thinks it’s fine to eat some more.
A deficiency in insulin thus leads to overeating, obesity and other nasty things.
The growth hormone-releasing peptide (the biologists tried to seem a bit more sophisticated by linking the name to the word gʰreh which means “to grow”) stimulates your appetite. It’s produced by your stomach when there is nothing in your stomach. Naturally, ghrelin levels decrease when you eat something.
And what happens if you give lab rats ghrelin?
They eat! What a surprise! And the same happens to humans!
I wonder who gave their okay for those human experiments …
Anyway, ghrelin is generally found in low concentrations in those with obesity and in higher ones in those who are starving. Which makes sense, if you think about it.
Yes, drugs can make you eat less. Cocaine- and Amphetamine-regulated transcript (CART) is partly responsible for that. A transcript is the stage between DNA and Protein: a part of the DNA is copied (“transcribed”) into RNA (something like DNA just slightly different in its structure) and then translated into a Protein.
So, this transcript is produced by neurons (cells of your nervous system). These neurons are stimulated by leptin and are connected to the parts of the brain that are responsible for reinforcement, reward, sensory processing, stress and endocrine (even more hormones) regulation.
If there is less food, there is less CART. If someone has a cocaine addiction, it changes the CART system. That’s bad because CART seems to be connected to the dopamine system.
Isn’t it fascinating how closely drugs and food are connected to each other? It’s not surprising that many people develop a food addiction.
There are even more hormones that influence what, how and when you eat, but this post is already a bit long and I don’t want to bore you. Instead, I will leave you with some thoughts:
Many people say their obesity comes from “a bad metabolism” or “bad genes”. While this might be true for some, it probably isn’t for most. But it might be worth to check for certain hormonal deficiencies when it comes to significantly overweight people.
At the same time, hormones aren’t something to play around with. Just a small increase or decrease can mess up your whole system. And how do you know how much of your behavior is actually controlled by hormones? How much of your personality?
As with everything, be responsible for the things you eat, the medication you take and the drugs you use. That doesn’t mean to cut out everything that might be dangerous (you can take my hormonal birth control from my cold, dead hands), but to be aware of the risks that come with it.
Sources:
Hormonal Regulators of Appetite
The CART (Cocaine- and Amphetamine-Regulated Transcript) System in Appetite and Drug Addiction
Picture taken from pixabay.com
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I have type 1 diabetes and I can say it's horrible when I'm uncertain if I'm hungry or I've just injected too much insulin and I'm feeling weak.
Mostly this is an issue, when the weak feeling comes from too low blood glucose and when I'm hungry, I might get paranoid "Oh shit, do I have low blood glucose levels?" - if I'm not able to measure the blood glucose level, I might eat something even though I wouldn't really need to.
And no, being hungry doesn't mean I would really need to eat something.
But the total amount of hormones related to hunger is interesting. I'm assuming everyone doesn't even know hormones have anything to do with hunger, simplifying it to "When you are hungry, your stomach is empty".
Yay.
I have Type 1 Diabetes to I completely understand your frustration @apsu . I now have an insulin pump I am able to regulate my levels and able to keep my appetite under control.
How long have you had it? I don't have an insulin pump, even though it could be handy I've always felt comfortable enough with insulin pens. However sometimes it's a bit too easy to inject a bit too much, but I'm still alive :)
@apsu thanks for asking, I have been type 1 for 13 years, I also used the pen and had that same issue with over and under injecting. it was a crazy roller coaster ride .
I have had the pump for about 3 years now and its amazing. I am able to control my levels a lot easier . no more lows or highs.
Please take care @apsu. My mom has diabetes my grandma died from it. I try to move a lot since I love loveove eating
I will :) Luckily if they have type 2 diabetes it's usually less serious, in a way...
But it always requires strength. So I wish your family will stay strong and hopefully you can avoid diabetes :)
Thanks for sharing @apsu.
It’s really interesting to see the point of view of someone who is really going through some of these issues. You made me reflective after reading your comment. Thanks for that.
All the best! :)
Very interesting information, thank you so much for sharing! I have never considered the effects of hormones and appetite before!
Hi @ suesa. This post did mention on diabetes and is what we have been taught. How ever I learned from a DR from india that all diabetes can be reversed. I'm no doctor but what he says makes sense so I am trying the method. Just started weeks ago. Will see the outcome.
JUst to share with the community. Video link below;
https://steemit.com/diabetes/@nkkb/39jyby-health-matters
I did some research on the balance of leptin and ghrelin that I found really interesting. For obese people, their hormone regulation is all off which causes them to have issues controlling their food intake. There is a lot we don't know yet about it though.
True @altherion so much about wellness is still undiscovered mine I just choose to be happy as happy peoplw are less likely to get sick
Very informative post. Thanks :)
Great stuff here!! Most people don't realize that their metabolism actually IS their hormones!! :-). Leptin isn't as commonly known!
What I think is absolutely insane is that neuropeptide F (NPF) is a homologue of our neuropeptie Y.
The fruit flies that have lower levels of NPF tends to drink ethanol more that the ones with higher levels. And there are also some studies, that uncover connestion between alcohol consumption and our neuropeptide Y.
How cool is that?
Btw, few minutes ago I made a tutorial post about how to draw Neuropeptide F. I mean, dont take it as a self-promotion, I just think it is a funny co-incidence :D
A lot of proteins are closely related because from a genetic standpoint they all come from the same gene. When a gene is replicated and you're left with two copies it leads to redundancy which means one version of the gene is able to go off and mutate into a new protein with a completely new function without harming the functionality of the organism!
Yea, I study genetics :D But the more I study the more mind-blown I get.
I know I just checked out your page. Great topic to study, I did my honours thesis in genomics... you're right that the lab work is dry! :/
Wow! Nice post as always. Hunger hormones, I never knew about them or let me say I never found out about them. I just know there are some times I get filled after eating only a little food and there are times I eat beyond my usual capacity.
This is so educative..
Suesa, the steemit chatter :)
You misspelled the "Science" tag.
"but this post is already a bit long and I don’t want to bore you. Instead, I will leave you with some thoughts:" No. please make it longer, don't be afraid that people won't read it, because if i was planning to read the whole post, I'll read it even fi it has more words to it.
I actually learned a lot from this post. So thank you for that.
Btw, I'm eating a lot, and tbh I think it's my heart that desires it
And it's the first tag, that means I can't change it... fuck.
I try to keep my posts at about 1k words, longer is usually too much for the readers ^^
1K words is a lot, you're right. but people can read more :)
have a great day
Hey, you still dint remove the misspelled tag!
And it remains as your main tag.
Oh, I just saw your reply to @yairdd.
Sorry😅
Thanks for rubbing salt in the wound :(
I swear 🙇.
I missed out on your reply @suesa
To forgive is Divine
I'm not divine tho. So I will NEVER FORGIVE YOU EVER
Because you can't change the main tag.
Good words there @yairdd I kept posting even if no one notice imagine what the world be like if the author of Harry Potter just gave up after being rejected many tines
Hi @suesa, The posts related to Biology always take me to my college days where not so weird Biology teacher used to speak about living things in an impressive way. I was very good Biology and all other subjects so my memories are mostly good. Your posts are very detailed and not as boring as those college days lectures. :) Pardon me, I did not mean what you have perceived. :p
So, here is what I have learnt from this post:
I'm good at grabbing the general idea of things though I can put my brain to remember details but naturally, that's not what I am. Just sharing with you because I did the same with this post after spending 11 precious minutes to read this post. :)
Great post @suesa. From now on, I'm going to remember you every time I'm very hungry or not hungry at all. :D
Steem On!