Presentation on theme: "Physiological Impacts of Alcohol"— Presentation transcript:
1 Physiological Impacts of Alcohol By C Kohn, Waterford Agricultural Sciences
2 AlcoholAlcohol for consumption has the same molecular structure as fuel ethanol: CH3CH2OHAlcohol is poisonous to the human bodyMany of the effects associated with consuming alcohol are actually a result of either the toxic impact on the body or the body’s method of coping with the toxinWhen alcohol is consumed, the body immediately tries to eliminate it.Alcohol is also a drug and can form both dependency and addiction
3 Pathway of AlcoholThe route taken by alcohol during consumption is as follows:Mouth & Esophagus – alcohol is diluted by saliva before being swallowed. Some is immediately absorbedStomach – more alcohol is absorbed here, irritating the lining of the stomach and increasing the aciditySmall Intestine – any remaining alcohol is passed here and is the site of most alcohol absorptionBloodstream – alcohol quickly diffuses through the body, affecting almost all cellsBrain - these cells are more susceptible because they are usually protected from toxins by the blood-brain barrierLiver – blood-alcohol is metabolized in two stages and then respired into CO2, H2O, and fatty acids.Excretion via urine, the lungs, and sweat.
4 Steps of MetabolismThe metabolism of alcohol is the process in which the body converts alcohol into a less toxic substance.Alcohol metabolism (processing) has three stepsConsumption – getting the liquid into your bodyAbsorption – absorbing the alcohol into your bloodstreamProcessing – converting the I) alcohol into II) acetaldehyde , then III) acetate (or acetic acid) and finally into fatty acids, carbon dioxide, and water
5 Consumption Consumption – mouth and esophagus 20% of consumed alcohol is immediately absorbed into the bloodstream before reaching the rest of the gastrointestinal tractAlcohol is an irritant to the sensitive lining of the esophagusExcess consumption can significantly raise your risk of esophageal cancer
6 AbsorptionAlcohol is absorbed into the blood through the stomach wallsThe emptier the stomach, the faster the absorption, the greater the impact, and the more pronounced the side-effectsAbsorption of alcohol also irritates the lining of the stomach, leading to some symptoms commonly associated with a hangover (nausea, vomiting, diarrhea)This also accelerates productions of hydrochloric acid in the stomach, leading to the ‘upset stomach’ feeling common with consumption and/or hangoverIf HCl secretion increases too rapidly or too high (or both), nausea and vomiting pathways are triggered.If vomiting does not occur, diarrhea is more likely for the same reasonAlcohol not absorbed by the stomach is absorbed in the small intestine (where most absorption occurs)
7 AbsorptionOnce in the bloodstream, alcohol is rapidly distributed throughout the bodyDifferent tissues absorb alcohol at differing ratesE.g. muscle absorbs alcohol more rapidly than fatPeople with higher percentages of body fat will absorb alcohol less quickly, lengthening the time it circulates in the bloodstreamWomen physiologically have a higher body fat percentage than men, typically increasing the impact of alcohol on their bodiesBody size also is a factor – the smaller the body, the more concentrated the effects will be (because alcohol will be a bigger proportion of the bodily fluid in a smaller person)Rate of absorption is also affected by rate and type of consumptionFaster consumption, faster absorptionCarbonated beverages also increase the rate of absorption – includes champagne, wine coolers, and drinks made with soda
8 Processing Acetaldehyde is then converted into acetate by ALDH Alcohol is processed by the liver as it arrives from the bloodstreamThe liver produces enzymes called alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH).Alcohol metabolism via ADH produces a secondary product more toxic than alcohol itself – acetaldehydeAcetaldehyde is then converted into acetate by ALDHAcetate is digested into fatty acids, CO2, and waterFatty acids, when digested, create 7 calories per gram of alcohol‘Beer gut’ has some truth to it
9 Overview of Processing Alcohol arrives at the liver via the bloodstreamADH turns alcohol into acetaldehydeThis is the “bad” versionALDH converts acetaldehyde into acetateThis is the “good” version that can be broken downAcetate is converted into CO2, H2O, and fatty acids by liver cell mitochondria. If fatty acids accumulate too fast, cirrhosis can occur
10 Effects of Alcohol Impaired Judgment Amnesia Anxiety “Breaking the Seal” – Increased UrinationFlushing (Red-Faced)Disrupted BalanceHangovers, Nausea, & Dehydration
11 Impaired Judgment Alcohol depresses the central nervous system This means that alcohol slows the rate at which the nervous system can function and communicateThis will prevent all neurological processes from occurring at the normal rate or extent ranging from judgment to control of bodily function.Structures of the brain affected include the frontal lobe where rational decision making and judgment occurs.Consumption of alcohol will also cause increased self-confidence as well as decreased judgment – a very bad combination.Those that are too drunk to drive are less likely to be able to make this determination as they drink moreThose that are too drunk too drive will also feel more confident in their own ability to safely do so (despite the contrary being true)
12 AmnesiaBecause the central nervous system is impaired, the process of creating and storing memory is also impaired.This can lead to short-term amnesia – excess alcohol consumption can cause people to be unable to form memories during consumption to varying extents.
13 AnxietyPart of the brain, called the amygdala, regulates human emotionThe amygdala is responsible for creating emotion appropriate for a circumstanceBecause alcohol depresses the central nervous system, the emotional regulatory function of the amygdala will also be impaired.This can lead to anxiety, anger, frustration, lust, and other primal human emotions to become over- or under-expressed.
14 “Breaking the Seal” “Breaking the seal” and Water Loss A common myth associated with alcohol consumption is that if you urinate once, you will have to urinate constantly – this is called “breaking the seal”In reality, you’ve ‘broken the seal’ as soon as you have your first sipAlcohol affects urination in 3 major ways –Alcohol is a diuretic, causing cells to shed waterAlcohol interferes with water reabsorption in the kidneys, causing excess water to be moved to the bladderAlcohol causes stretch receptors ‘miscalculate’ the amount of urine in the bladder, making it feel fuller than it is.A combination of excess water lost, reduced water reabsorption, and a miscalculating bladder creates the need to urinate more frequently with greater consumption.
15 Thinned Blood Alcohol is a blood thinner Alcohol has a lower density than waterThis is why alcohol floats on top of waterConsumption and absorption of alcohol will reduce the thickness of your blood.Moderate consumption of alcohol (< 2 drinks per day) by legal adults can actually improve heart health by lessening the work required to pump bloodThinner blood is easier to pumpDo not self-diagnose!
16 FlushingA common symptom of inebriation is flushing, or being “red faced”Flushing in the face is due to an excess of acetaldehyde in the body, a decrease in the ALDH enzyme, or both.Because acetaldehyde is more toxic to the body than the alcohol itself, it can cause an inflammation response similar to injury or infection in skin blood vessels.
17 Lost BalanceBalance is regulated by the semicircular canals inside your ear.The semicircular canals are looped structures that are filled with fluid called endolymphThe movement of fluid inside these loops tells your body your position and orientation in spaceAlcohol thickens this fluid, reducing the ability to sense movement.The sensory system responsible for sensing movement is now less sensitive, causing stumbling and loss of coordination and balance.The cerebellum (muscle coordination center of the brain) also is impaired
18 HangoversA hangover is the ill-effects experienced by excess alcohol consumption after the ‘high’ of alcohol has worn off.Symptoms of a hangover include:FatigueDehydrationNausea & Stomach IrritationHeadache
19 FatigueThe exhaustion associated with excess consumption is due to alcohol’s inhibition of glutamineGlutamine is a bodily stimulant whose production is inhibited by alcoholWhen the effects of alcohol wear off, glutamine production is increased to compensate for previous inhibitionThis causes a drinker to wake more in their sleep as glutamine production increases, preventing the deepest and most restful stages of sleepGlutamine rebound can also lead to tremors, anxiety, and restlessnessGlutamine, like caffeine, is a stimulantExcess glutamine production is going to have effects similar to excess caffeine consumption
20 Dehydration Alcohol is a diuretic and causes cells to shed water. Alcohol also interferes with the kidney’s ability to regulate water balance in the bodyJob of an aquaporin protein is to regulate reabsorption of water filtered out of the blood by the kidney.Vasopressin is a hormone that regulates whether or not an aquaporin channel is openAlcohol inhibits the function of vasopressin, limiting its ability to open aquaporin channels that would let filtered water back into the bloodstreamThis causes water to be moved to the bladder at an increased rateThis coupled with the diuretic effects of alcohol leads to a dehydrating effect when consumedOpened by Vasopressin
22 Nausea & Stomach AcheStomach Irritation is largely due to excess production of HCl in the stomach as a result of absorption into the bloodstream through the stomach lining.Excess hydrochloric acid increases the acidity of the stomach, creating the ‘sour stomach’ feeling in a very literal wayIf the pH of the stomach drops too much or too fast (or both), it will cause vomiting, diarrhea, or both.This can also be caused by a ‘fight or flight’ response of the body due to the poisonous nature of alcohol
23 HeadacheA headache can be due to numerous effects of alcohol, including –Inflammation of blood vessels, creating pressure in the skullDehydrationAcetaldehyde’s presence in the bloodIncreased stimulation and anxiety caused by glutamine resurgenceStress from nauseaA combination of all these and more
24 Cures to a HangoverThere is only one truly effective cure to a hangover – TIMEPain relievers that do not contain acetaminophen can lessen perceived pain but not actual damage (aspirin can cause increased liver damage)Caffeine is a diuretic and will compound damage caused by water lost and dehydration“Hair of the Dog” or drinking again in the morning to lessen a hangover, only worsens the problem while lessening the perception of it (for the time being)
25 Cures to InebriationSimilarly, you cannot “sober up” with anything other than time.Caffeine will not reverse the depresion of the central nervous system, thicken your blood, restore your balance, or negate any other effects of inebriationWhat’s worse, mixing an ‘upper’ with a ‘downer’ (caffeine with alcohol) can cause the brain to send conflicting signals to organs such as your heart and lungs.Stimulant/alcohol combinations can lead to heart or lung failure.Consuming food to sober up will not reduce the amount of alcohol already in your bloodstreamAdditionally, you cannot ‘fool’ a blood alcohol meter.
26 Long Term Effects of Excess Consumption Tissue damage – alcohol is an irritant to the mouth, throat, and stomach and can raise the risk of cancers to these structuresLiver Damage – the liver can be overwhelmed by fatty acid, causing it to swell and lose its ability to filter the body of other toxinsBrain damage – alcohol can permanently damage brain cells, particularly in brains that are still developing and maturing (the brain does not finish maturing until age 20-25).Weight gain – alcohol has 7 calories per gram. This is almost as high as pure fat (9 cal) and higher than carbohydrates (4 cal/g)Skin Damage – the conversion of alcohol into acetaldehyde causes inflammation.Excess consumption will cause excess inflammation that can lead to the rupture of blood vessels in the skin creating blotchy scarring.Accidents – impaired judgment, lost coordination, and an increased sense of confidence is a deadly and all-too-often fatal combination.