Sugar and carb addiction addiction

On carbohydrate addiction addiction
MFP tends to get a sugar / carbohydrate addiction thread about once a day. As such, I thought it would be helpful to have something explaining the neurobiology of what happens in classically addictive substances like cocaine, and why similar chemistry in food consumption might sound like the same thing when reported by lazy science writers throwing out hyperbole for click-bait.

First forewarning – this isn’t meant to belittle or deny anyone’s experience. I am one of the cold science meanies some of MFP hates, but philosophically, I very much believe in compassion and acknowledging people’s experiences – so yes, I’ll validate your feels, and be a hugbox if you want, but only those feelings, and only when asked for. if you want to spout bad or pseudoscience, I won’t validate it not only because I care a great deal about scientific knowledge and process, but also because I believe self-delusion is unhealthy. More so, what I’ve found while studying neuroscience as an amateur enthusiast is that what the brain experiences is real – the humans haven’t evolved new abstract ways of feeling, we’ve just mapped a lot of abstract concept onto physical feedback systems as old as reptiles.

Second – I’ll admit, I’m not a neuroscientist, and as a learner, I’d appreciate feedback and corrections by anyone with knowledge or sources.

On brains makes telephone calls
I’m probably ruining it for anyone interested in quickly looking for something to disagree with, but I think it helps to start by actually understanding the main neurotransmitters involved cocaine, two of which are also involved in eating, and all three of which are involved in depression, which is what started my interest in the subject.
Anyway, sending signals across the tiny distances between neurons in the brain is actually a pretty daunting task. Poor guys can’t even send calls out describing what they want to, they have to kind of write messages in a bottle and chuck it. To make it worse, they can’t even write the message they want, they tend to have to toss neurotransmitters that can be pretty vague and mean sometimes almost conflicting things. Serotonin, for example, is actually 90% in the guts, and yet, lack of it the brain makes you feel kind of crappy. So yeah, you’re brain’s signals are kind of loose, it’s had to rewire the flush it out the body signal to flush it out of your mind signal.
Norepinephrine – this is the one that isn’t involved much in food. It does activate pleasure centers to an extent, and as far as weight loss goes, the most interesting thing is that norepinephrine is that lack of norepinephrine is pretty involved in psycho-motor retardation: the type of nerve fatigue that involves not moving. In CICO terms, it is pretty important for CO, but not as important in controlling CI.
Dopamine – this is probably one of the most misrepresented molecules ever. If someone has heard of dopamine, the off the cuff explanation is that dopamine is the reward chemical of the brain. Well, that’s great, so how do you explain the fact that people with a gambling itch get dopamine signals whether they win or lose, or before they’ve even shook hands with a one armed bandit? Why is that when you hook up a device for rats to activate the dopamine pathways at the push of a button, you see the most response not when the button works every time, but only intermittently? I’d say it is far more accurate to call dopamine the reward ANTICIPATION chemical – and that makes an important distinction in explaining food later on. Some researchers even consider dopamine the incentivizing chemical because it also appears to go off in relation to pain – possibly saying, “pay attention, let’s get away from the large predator mauling us before we lose any more fingers”. I’m still waiting for the addiction people to explain to me why dopamine lighting up an in MRI means we’re addicted to carbohydrates, but no one says we’re addicted to getting pin pricks when MRI scans show dopamine activity too.
Serotonin – serotonin is an inhibitory neurotransmitter. For humans, it has effects on appetite, impulse control, and can prevent obsessive / repetitive thoughts. The latter two are why serotonin is a very common target for anti-depressant and anti-anxiety medications. Despite being inhibitory, excessive serotonin is also associated with hallucinations, such as caused by psychedelics. Of particular interest is the fact that eating activates serotonin, which then down regulates dopamine to reduce appetite.

Pixie sticks vs pixie dust
So, now that we know something about neurotransmitters, let’s look at the excessively simple explanation of what happens with neurotransmitters when eating sugar (potentially any food, but sugar gets the bad rap these days), or when taking cocaine.
Eating sugar: dopamine goes up, spikes, serotonin goes up, dopamine goes down, serotonin eventually lowers as well.
Cocaine: dopamine goes up, stays up a long time, serotonin goes up, stays up a long time, norepinephrine goes up, stays up a long time.

SEE, SEE! THEY’RE ALIKE! IT’S ADDICTION
Remember that part where I said let’s look at the excessively simple explanation? Up your serotonin (control yourself) and follow along at what is very different.
To begin with, it was already said, dopamine isn’t about reward, and that is very important: food is a reward (but please don’t reward yourself with food). I kind of tricked you, dopamine goes up on detecting food, not eating it. You can even get similar effects to happen setting up the classical condition of having a dog condition to anticipate food when a bell rings, and last I checked, no one thought we’d ever caused dogs to have bell addiction. Serotonin actually rises to turn off dopamine as you ingest – you got the reward, let’s stop looking around for more, maybe even find a comfy spot, you know? You found the food, you’re going to survive and maybe reproduce, so hey, we can afford to be a little more still. The cycle actually tends to limit itself.
So what happens with cocaine? Cocaine is a reuptake inhibitor for norepinephrine, serotonin, and dopamine. Normally, neurotransmitters get recycled all the time (yeah, your brain drives a Prius, get over it), but a reuptake inhibitor tends to jam up the recycling center, and instead, you wind up with neurotransmitters activating neurons over and over again. Normally, like when neurotransmitters handle your appetite, activation upregulates recycling, so there’s a balance. I’ve not personally been around it, but I’m told balanced is not a word normally associated with cocaine use. With the reuptake pumps inhibited, the flooding means a person on cocaine has dopamine causing a high state of arousal (not that kind of arousal, this isn’t the chit-chat forum), serotonin is elevated to the levels that can cause hallucinations, even norepinephrine is up. All of this is recipe for someone that isn’t sitting still any time soon. That’s quite the difference.

But I eliminated da carbzzzz and I got better
Well, let’s look at it in terms of what your neurotransmitters were kludged into working on – problems of existing on the plains of Africa. Normally, finding food, particularly starches, can be hard. It can take work, and you once you find it, you might need to sit still chewing or pounding for a long time to get all those carbs out. Serotonin’s coming in stops dopamine from making you wander around looking for more. Now, in a modern home, find and consuming carbohydrates is relatively easy – it doesn’t take much wandering, and therefore, not much pushing from dopamine. People who eliminate carbs and put them out of their home as a form of elimination diet are kind of repeating this. Yeah, getting in your SUV and going down to the grocery store to get ice cream is less effort than wandering the plains of Africa, but still, it is upping the amount of reward anticipation needed to drive the behavior compared to having it sitting around the house.
In comparison, cocaine keeps arousal and desire high. People will go through incredible painful (both psychologically and physically) to go find more cocaine.

But I had withdrawals like addicts
LOL, no, you didn’t. Keto flu is what you might have had. You can’t detox sugar from your body the way a drug user detoxes the drug from their system. Your body MAKES sugar (glucose) because your brain and a few other things require it to make somethings happen. Yes, ketogenesis can cause the brain to use more ketones than normal for fuel, but your brain will essentially beg, borrow, and steal (including breaking down tissue to steal sugar from the amino acids) to keep up the necessary pathways.
Meanwhile, there also huge differences in what has happened to the neurons between someone giving up carbs, and someone giving up cocaine. All of that force signaling via neurotransmitters that cocaine caused? Well, the neurons don’t like being told to stay constantly alert, and thinking your body is out of balance, they adapt to reduce their receptors to handle what they see as a malfunctioning signal. So, now the cocaine addict comes down, gets it out of their system, and their neurons aren’t reacting ENOUGH to the neurotransmitters like a normal person. This is part of the physical withdrawal that is often clinically called physical dependence to distinguish it from people arguing over what is or isn’t addictive. I’ve yet to hear of sugar addiction causing this kind of negative feedback loop, but I’d be happy to see evidence of it.