A hangover occurs when you drink too much alcohol. How much is too much? The amount is different for everyone. Some people can tolerate a whole lot more than others.
When you drink too much alcohol, some acute changes happen in the brain that affect your neurotransmitters. You can get vascular changes, such as constriction and then over-dilation, which is what gives you that pounding headache. The neurovascular inflammation occurs when the nerves that line the blood vessels in your brain become inflamed from too much alcohol. That’s very painful and can lead to the migraine-like symptoms.
Physical Effects of a Hangover
Alcohol is toxic to all tissues in the body, particularly when it’s consumed in excess. When you drink too much for your gastrointestinal system to handle, it causes nausea. Alcohol kind of stuns your GI system, so you get what we call an ileus, meaning it’s slow and it doesn’t want to take in food. Everything you eat kind of sits there and feels like a rock.
Dehydration is also a big part of a hangover. Your blood sugar levels are affected by how efficient your body metabolizes alcohol. There’s a specific enzyme called alcohol dehydrogenase that helps break down alcohol. Some people’s bodies make it very efficiently, so they can tolerate a lot of alcohol. Oddly, those people struggle with alcohol overuse, because they can tolerate so much of it. Other people don’t make very much alcohol dehydrogenase, so they have a lower tolerance for alcohol. They tend to stop after one drink because they just don’t feel well.
Most people fall somewhere in the middle. The efficiency and amount of alcohol dehydrogenase that your body makes also plays a big role in whether you get a hangover and how quickly you can get over it. Your body re-regulates the system usually within hours when you have a hangover. The danger comes with chronic use of alcohol. Then it’s much harder for your nervous system to re-regulate, taking days, not hours, and this can cause permanent damage.
Chronic Overdrinking Damages the Brain & Body
Drinking alcohol initially makes you feel good. It affects the mesial limbic area in the brain, where we process emotion. It's the one place where you get that reward because it causes a release of dopamine and all these feel-good neurochemicals initially, which inspires us to keep drinking. It’s hard for people to stop even when they’ve had too much to drink because that reward is so powerful.
Dopamine's a very powerful neural chemical that makes us feel really good. We feel up. We feel happy. With chronic alcohol use, however, you can deplete your dopamine stores and your body’s gamma-aminobutyric acid. GABA inhibits nerve transmission in the brain, allowing your body to calm nervous activity.
Chronic alcohol use also damages your body’s autonomic regulation, or your temperature, blood pressure and heart rate. People who drink every single day cause great damage to that particular part of the nervous system as their bodies struggle to re-regulate. If you're drinking every single day and then you take it away, all those neurochemicals are now absent. The dopamine is gone, the GABA is gone, and your nervous system kind of goes haywire.
For some people, this feels like withdrawal, where they get the sweats, the shakes, and lots of anxiety. Their blood pressure goes way up, their heart rate goes way up. That's the nervous system saying, “Wait a second, all of our neurotransmitters are out of whack here!” It feels pretty bad.
Hangover Prevention Tips
One of the best ways to avoid a hangover after drinking alcohol is to eat beforehand and make sure you are well hydrated. The best prevention tip, however, is just to know when to stop drinking. When you start feeling like you’ve had enough, just stop.
For women, in general, drinking more than seven drinks per week is considered overuse. For men, drinking more than 14 drinks per week is considered overuse. While those are general rules, everyone’s body varies in how much alcohol they can tolerate.
If you think alcohol consumption is damaging your body, come see me at at Olp Family Medicine of Carmel. We can help you find ways to limit your alcohol use or eliminate it altogether.