Important facts about alcohol that you won't find on the label... The standard summary of alcohol metabolism is that the human liver can process one unit / one 25ml 40% ABV / 80 proof of alcohol in one hour, and exceeding this results in intoxication and a buildup of toxic metabolites which partly cause a hangover. After regular consumption of alcohol, especially in heavy users, the liver can actually increase heptic enzymes to metabolise around three units/ 75ml 40% ABV / 80 proof of alcohol per hour. However, acetaldehyde volume and tolerance does not change, meaning harder and more heavy doses of alcohol to stay drunk but the same damage to the liver and brain as that of a new or irregular drinker. The main cause of shaking, anxiety, and general symptoms in a hangover is due to the brain upregulating levels of glutamate since alcohol inhibits this chemical. It takes around 1 year of binge alcoholism to reduce liver function by 40% and around 10-25 years of regular continued drinking for liver function to fall to dangerous and irreversible levels. Symptoms may not be apparent to the drinker until as low as 10% liver function, although in most cases other organs will display symptoms of failure by this point. In the brain, alcohol causes permanent changes in NMDA receptors similar to those seen in regular heavy abuse of nitrous oxide (balloons) or laughing gas; a defiency in GABA and a pro-efficancy in glutamate and dopamine. These cause seizures, delirium, and in most cases, death upon long-term heavy alcoholism. Without specialist help with targeted medication, severe alcoholism can be a death sentence during sudden abstinence. Despite being a depressant, some of its effects on GABA, serotonin and dopamine make it by nature one of the most addictive chemicals on the planet, including cocaine and opioids. I am also happy to answer any questions you have or regarding these facts. Please drink responsibly and remember that this is a drug too and is hazardous to physical and mental health. Glutamate: A chemical that causes neurons in the brain to become excited and is describable to that of a natural stimulant. GABA: A chemical that causes neurons in the brain to slow down, or basically stop communicating with each other as efficiently, which causes the relaxing and euphoric effects of drinking. Dopamine: Various purposes, but in respect of drinking causes a vast amount of reward activation in the area of the brain responsible for behavior, the same as cocaine and heroin. Serotonin: Various purposes, but in respect of drinking causes impulsive emotional states, orgasm suppression and enhances GABA. NMDA: Key in the signature of various areas of the brain and functioning of neurons. When chronically altered by substances, can cause severe fatigue, nausea and vision changes. Sensitive to B12 deficiency. Acetaldehyde: A byproduct of alcohol. It has no purpose within the body and causes brain shrinkage, thinning of the blood, death of cells in the liver and accelerates glutamate effectiveness at post synaptic receptors, in the short term a major reason for hangover effects described above plus headache and vertigo. This starts within 5 minutes of the first drink and in small amounts, can be processed without a hangover or damaging effect, but drinking more than the body can process i.e getting drunk and mainly binge drinking - long term causes accumulative damage. Thank you. Sources: Imperial College London, Pysconaut, Wikipedia;alcohol, Talk to Frank, Wikipedia;GABA, NHS