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Valerie Schulz, MMSc, RD, LD/N, CDE
Alcohol Intake
On average, people in the United States
consume from 6 to 10 percent of their
total daily energy intake as alcohol
(Beer: 100 – 150 kcal /12 oz; 150/2000 kcal = 8%.
 Wine: 100 – 120 kcal / 5 oz; 120/2000 kcal = 6%)
A third of U.S. college students drink
alcohol in patterns of binge drinkers
 (What is criteria for binge drinking for
women? Men?)
The National Institute on Alcohol Abuse and
Alcoholism defines binge drinking as a
pattern of drinking that brings a person’s
blood alcohol concentration (BAC) to 0.08
grams percent or above. This typically
happens when men consume 5 or more
and when
women consume 4 or more drinks, in
about 2 hours.1
 1.
Alcohol in beverages
Alcohol Action
Alcohols affect living things profoundly:
 act as lipid solvents
 Alcohols can easily penetrate a cell's
outer lipid membrane
 once inside, alcohol denatures cell
protein structures and kills the cell
As an example of the action of alcohol:
some alcohols kill microbial cells, they
make useful disinfectants and antiseptics
(rubbing alcohol, hand sanitizer)
Ethyl Alcohol (Ethanol = EtOH)
Alcoholic beverages = ethanol
 somewhat less toxic than other alcohols
 Sufficiently diluted and taken in small
enough doses, its action in the brain
produces euphoria
 Used in this way, alcohol is a drug, and
like many drugs, alcohol presents both
benefits and hazards to the taker
How much is a drink?
Beer: _____ oz (4-5% alcohol)
 Wine: ____ oz (12-14% alcohol)
 Wine cooler (commercial): _____ oz
 Hard liquor: _____ oz (80 proof)
 What does proof mean?
 80 proof = ______ % alcohol
 A serving
of alcohol is called a drink,
and delivers ½ ounce of pure ethanol
So here’s a question:
How many ‘drinks’ is one can of Four
 23.5 ounces, 12% alcohol by volume
○ One ‘drink’; it’s only one can
○ Two and ½ ‘drinks’; that’s a BIG can!
○ Three ‘drinks’: the volume is like 2 cans of
beer, but the alcohol % is higher
○ Almost five ‘drinks’: the same alcohol % as
wine, and since a ‘drink’ of wine is 5 oz,
23.5oz / 5 = 4.7 ‘drinks’
Definition of moderation
No more than:
 1 drink a day for an average woman
 2 drinks a day for an average man
These are 24 hour maximums
(Why is moderation different between genders, even
though a man and woman might weigh the same? The
answer will be later in the chapter under the heading
“Alcohol Arrives in the Liver” , and then under heading
‘Alcohol breakdown in the stomach’ ; also on slide 21)
(ie, no drinks all week and 7 on Saturday is
NOT moderation; that’s ___________
Who should not drink?
People of any age who cannot restrict their drinking
to moderate levels
Anyone younger than legal drinking age: (increased
risk of drowning, car accidents)
Women who may become pregnant or who are
pregnant or breastfeeding: alcohol may be
especially hazardous during the first few weeks,
before a woman knows she is pregnant
People who plan to drive, operate machinery, or
take part in other activities that require attention,
skill, or coordination to remain safe.
People with medical conditions: HTN, liver disease
Moderate vs problem drinkers
Compare characteristics in chart C3-4 pg 98 –
(titled: Behaviors typical of Moderate and Problem
Harm from binge drinking:
 Fatal car crashes
 Alcohol related assaults, including sexual
○ (600,000 college students per year)
 1,700 college students die from these injuries
 Unplanned pregnancies
R. Hingson and co-authors: Magnitude of alcohol-related mortality and morbidity among
US college students age 18-24: Changes from 1998-2001, Annual Review of Public
Health 26, (2005), 259-279.
Personal aside
Because we are not in the classroom, where I
could verbally add some tidbits, I will have to
do it by typing…
 A good friend, who has been ‘clean and sober’ for
28 years, has caused me to widen my eyes in
surprise over her tales of drinking for days at a time,
blacking out, going to work drunk, and about two
months ago, telling me she drove home from work
gripping the steering wheel tightly to keep the car
pointed toward home because she wanted a drink
so badly – after 28 years! She says, “I have alcoholism, not alcohol-wasim.”
 This same friend has an male AA friend who says
(with a wry grin), “I know when I’ve been drinking,
because I land in jail!”
Alcohol enters the body
Requires no digestion
 Tiny* alcohol molecules start diffusing right
through the stomach walls and they reach the
brain within a minute
 drinking on an empty stomach = quick
When stomach is full of food:
 molecules of alcohol less chance of touching the
stomach walls and diffusing through
 alcohol reaches the brain more gradually
 Also, a full stomach delays alcohol's flow into
the small intestine, allowing time for a stomach
enzyme to destroy some of it
 in small intestine, alcohol is rapidly absorbed
whether food is present or not
* See next slide
Ethyl alcohol – small molecule
About as
big as 3
Alcohol enters the body
increased urine output (because alcohol
depresses the brain's production of antidiuretic hormone)
 Loss of body water leads to thirst (drink
actual water between alcohol drinks, otherwise
just get thirstier)
water lost due to hormone depression
takes with it important minerals:
Rate of drinking
drink slowly enough and the alcohol will
be collected by the liver after absorption
and processed without much effect on
other parts of the body
more rapidly, however, some of the
alcohol bypasses the liver and flows for
a while through the rest of the body and
the brain.
Alcohol’s effect on the brain- Figure C32, after heading “A Lethal dose of Alcohol”, pg 99
Alcohol in the Brain
Inhibitory nerves are sedated, allowing
excitatory nerves to take over, giving the
impression that alcohol stimulates
 (it’s really a depressant)
Table C3-5: Blood alcohol Levels and
Brain Responses, pg 100: what blood
alcohol level is consistent with death?
Alcohol metabolism (brief)
 Ethanol
ADH = alcohol dehydrogenase (removes hydrogens)
ALDH = aldehyde dehydrogenase
Acetaldehyde: carcinogenic, short lived
(do not have to read this whole article, I put it here to
corroborate the carcinogenicity of acetaldehyde)
Alcohol metabolism (brief)
During the breakdown of alcohol, also get
free radicals, which attack
 Brain cell lipids, causing inflammation (also
referred to as oxidative stress)
 Inflammation linked to diabetes, cancer, CVD
ADH converts about 80% of alcohol
consumed; other enzymes will help if
alcohol intake exceeds capacity of ADH
Alcohol around the body
If more alcohol arrives at liver than
enzymes can handle, continues to
circulate through brain, liver, other organs
until enzymes available
 Stomach wall produces ADH
 men make more ADH than …
 women; (so woman absorbs more EtOH from each drink)
 people dealing with alcoholism make less than
those not struggling with the disease
Excretion in breath and urine
~ 10% of alcohol in blood is excreted as
is (as ethanol) through
 Lungs (breathalyzer directly proportional to
alcohol in blood, so is accurate test of BAC)
 Kidneys (urine)
Rate of clearance: (good to know…)
 One drink per hour (1/2 oz of ethanol)
 Fasting even for one day can degrade body
proteins, including ADH, and reduce the rate of
alcohol metabolism
 Walking (muscles cannot metabolize alcohol) or
coffee (only makes you alert & drunk) does not
speed up rate of alcohol metabolism
Processing of alcohol
EtOH receives highest priority
Cannot be stored without first being converted
to something safer
Acetaldehyde (first breakdown product) can
bind to and disrupt enzyme and cell function
Progression of liver damage
Fatty liver
 acetate leads into fat synthesis
 Liver busy detoxifying alcohol, slower to package
 Fatty liver remains for > a day after single night of
heavy drinking; reversible
 If drinking continues, fibrous scar tissue invades
 Reversible with abstinence and good nutrition
 Liver cells harden and die – not reversible
Consequences of cirrhosis
Remember that all the nutrient rich blood from
the GI tract flows into the portal hepatic vein,
directly to the liver
Once the liver cells have hardened, it is much
more difficult for them to receive the flow of
this fluid
Backpressure occurs, forcing the fluid that
used to go through the liver to pool in the
abdomen: ascites
Ascites (def): The accumulation of fluid in the
peritoneal cavity, causing abdominal swelling.
Note the thin
extremities (he is
not fat all over) and
the bulging belly
button (fluid
pressure). Imagine
his effort to breathe
when he lays
down, with all that
water weight
pushing against his
Alcohol effects around the body
May suppress testosterone
 Slows synthesis of immune system
 Synthesis of blood lipids speeds up,
increasing triglycerides and HDL
 Excess alcohol interferes with normal
uric acid metabolism, causing gout-like
Mild form drug withdrawal
 Alcohol reduces water content of brain
cells; swelling back to normal size with
rehydration the next day sets up nerve
pain (headache)
 Same enzymes process both ethanol
and methanol (produced in tiny amounts
by cellular processes), but prefer
 Methanol’s first breakdown step is
Both alcohols processed without delay
until acetaldehyde monopolizes the
second set of enzymes
 This leaves formaldehyde to wait, starts
accumulating and the hangover begins
 Methanol →
Time alone is the cure for a hangover.
Long term effects
○ Devastating to a fetus (we will cover in detail when
get to chapter13)
Cirrhosis develops after 10 to 20 years of heavy
Bladder, kidney, pancreas, and prostate damage
Bone deterioration and osteoporosis
Brain disease (attacks brain cells directly), CNS
damage, strokes
Deterioration of testicles and adrenal glands
Diabetes (type 2)
Disease of heart muscles – (alcohol is toxic to
muscle and raises blood pressure → alcoholic
Feminization and sexual impotence in men
Impaired immune response
Long term effects
○ Impaired memory and balance
○ Increased risk of death from all causes (Incl
Nonviral hepatitis
Severe psychological depression
Skin rashes and sores
Ulcers and inflammation of the stomach and
Alcohol’s effect on Nutrition
Alcohol does damage indirectly via
 Not likely a person will eat enough food if they
drink a lot
 Provides empty calories
 Disrupts tissue’s metabolism of nutrients
 Wernicke-Korsakoff syndrome – a thiamin
deficiency (poor muscle coordination, impaired memory,
nerve damage including paralysis of eye muscles)
 Pellagra, beriberi, scurvy, protein-energy
malnutrition: all due to getting kcal from alcohol,
not food
Alcohol in moderation
Alcohol in moderation may reduce risk of
 Heart attacks
 Strokes
 Dementia
 Diabetes
 Osteoporosis
 Lower mortality in adults >35 years old
Alcohol in moderation
1 to 2 drinks a day are credited with reducing
the risk of death from heart disease in people
over 60 years old who have an increased risk
of heart disease.
A study showed an increased risk of death
from all causes with more than 22 drinks per
week (avg 3 drinks /d) and that men drinking
more than 35 drinks a week (avg 5 drinks/d)
had double the mortality from stroke compared
with nondrinkers.
Alcohol in moderation
So there is a fine line between the
reported health benefits of 1-2 drinks per
day, and the poor health outcomes from
3-5 drinks per day…
Dealcoholized wine, purple grape juice
and the grapes themselves contain
phytochemicals (resveratrol) similar to
those of wine but without the potential
dangers of alcohol
Alcohol terms to know – pg 96 –
From Table C3-1, after “Defining Drinking”
alcohol dehydrogenase
fatty liver
Wernicke-Korsakoff syndrome