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Avatar universal

Does fasting affect Liver Ast/Alt tests?

Does fasting typically affect the liver function tests?  My doctor told me I didn't need to fast before a bunch of tests that were recently done.  So I ate lunch (bean burrito) and had a diet coke about 2 hours before the tests ... I need a clean bill of health for a job I have been offered.

Liver function tests were high as well as sugar.  I'm sure the sugar was caused by eating but what about the liver function tests?  They weren't *way* out of line ... AST was 60 and ALT was 85 I think but could have the numbers reversed.  Pretty sure I don't have hepatitis ...

* Male
* 6'0", ~210lbs
* drink moderately (2 drinks a night, 4-5x a week).  
* pretty active generally
* have been injured for much of the past year--could stand to shed a good 20-30lbs
* most of my extra weight in the mid section
at 6'0" 210lbs.  
* vegetarian

Will be getting a retest in a couple days.  Anything to eat or avoid in the days before the test?   Am I a likely candidate for a fatty liver?  I am not *fat* by any real measure but do have some extra weight around the middle.
24 Responses
96938 tn?1189803458
Avoid the alcohol for a few days, if you are able. I once knew a guy very well who was very smart, except about small numbers. He was always getting 2 and 5 confused.
Avatar universal
Eating before will affect glucose but not LFT's. Alcohol day or two before test will raise ALT & AST's.

Also any meds like tylonol, etc can raise LFT's.

Since you said you are over weight in mid-section possible fatty liver.

You may want to rule out hepatitis if those #'s don't go down.

179856 tn?1333550962
drink moderately (2 drinks a night, 4-5x a week).  

Yes alcohol likely is the culprit  (for the sugar perhaps) and the liver enzymes if anything.  Next time, fast from the night before and take the test in the morning and see what happens.
979080 tn?1323437239
When you do tests the number 1 rule is be consistent.

When I first started testing I thought it is best to fast before
but I got tired of skipping breakfast and having to go to lab
in the am (busiest time to go to drawing station)

since I have no glucose problem I now go in the pm and I expect
my glucose to be high after lunch , no big deal.

in terms of alcohol , meds ect.... common sense applies
Avatar universal
I decided to get tested when my LFT's were just above the cut-off; around low 40's.

I didn't drink and figured that they should be lower.  It turns out that was positive for antibodies.  I'm glad that I got tested, and even more glad that I wasn't a heavy drinker.  It's tough getting diagnosed, but it is far worse being infected and not knowing it.

Why not get an elisa or riba antibody test based on your high LFT's?

Also..... I'm not a doctor..... but I believe that the protocols for getting accurate test results recommend fasting prior to blood draws.  If this was an important test that a job or insurance hinged upon having good scores.....I'm not certain you got good advice.  Fasting only would have improved your scores, I believe.  

Hmmmmmm......why are you getting retested in a few days?  Is it because the tests were invalid due to not following the fasting protocol?  Or that they were too high and you now want to lower them?

I would avoid drinking from NOW right up to when you are tested.  No painkillers/ NSAIDS, Tylenol etc.  They see what your liver function tests look like.  Since you are getting retested why not get an antibody test as well?  They are cheap and you are there anyway.  Avoid any rigorous exercise since that will also raise LFT's (the destruction of tissue raises LFT's  (I *think* it's ALT; not AST.  One of them.  ; ) )

By the way...... my slightly high AST and ALT scores were low enough that my doctor pooh-poohed the idea that I might have some form of hep.  Turns out that he was dead wrong.  Having the test results and that small bit of information that I was probably one of the smartest things that I ever did....... and yes, against Dr's advice.

Avatar universal
I think the primary reason for fasting is the blood glucose test. I doubt that eating would affect LFTs.

"...For example, males have higher transaminase levels than females. And, African-American men have higher AST levels compared with Caucasian men.  Even the time of day that a blood sample is drawn may influence the level of transaminase elevation. People appear to have higher transaminase levels in the morning and afternoon than in the evening.  Food intake does not appear to have a significant effect on transaminase levels.  Thus, levels do not significantly differ in the fasting and non-fasting state.  Finally, transaminase levels may vary from day-to-day...."

179856 tn?1333550962
To be honest I don't know why I said or implied that fasting might change your liver enzymes - alcohol yes but food no. I never fasted for an enzyme test unless it included my cholesterol.

Sorry sometimes at work I go to fast and then look at what I've written and realize it is absolute garbage with no basis at all. I know what meant but I don't believe in any way fasting would change your liver enzymes.
190885 tn?1333029491
sounds to me like your an alcoholic...maybe not too bad yet but on the way...it's real hard to admit you have a drinking problem...i would try stopping all drinking for a year or so...it will really help you lose weight and should make you feel better...and will most likely bring your alts and asts down..good luck....billy
1117750 tn?1307390169
2 drinks a night for 5 days a wk , hardly an alcoholic
Avatar universal
If you have hep C there is no good amount of alcohol.
979080 tn?1323437239
alcohol is a naturally occuring substance

let`s not completley demonize it

I was socially drinking before dx , especially the week before

my first PCR I just got back from a vacation with nightly cocktail hours ect...

I stopped to zero after dx and to this day my first VL is the lowest despite

alcohol , diet ect....

My father was dx at age 70 (geno1 , VL 400k) He is now 82 enjoys a glass

of red wine here and there has no fibrosis and generally does not think about

Hep C.

Just saying................

common sense is to omit alcohol yet studies show that even with Hep C alcohol

consumption has to be significant to really make a difference.
Avatar universal
I wouldn't mind having a drink every once in a while, but I am doing my best to preserve my liver in the hope that I will rid myself of this virus before the damage has gone to far, so I don't drink at all. Everyone makes there own decision about what's most important to them. At least we should be well informed!
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