Medical experts? Question on fasting before blood test

Lady who works for me has to have a blood test at 8:00 AM in the morning. Pretty basic lab work, plus looking for any thyroid malfunctions. So they tell her she has to do the standard 12 hour fast/only water for tonight.

Which really sucks, because she is hosting a pre-superbowl party tonight, and she really would like to be able to drink a little later than 8:00 PM tonight. She asked me if the blood test would really be any different or effected if she had a drink after 9:00 or 10:00 PM tonight, if she stopped at say 10 or 11:00 PM.

I told sorry, I’m a Ph.D. and not an M.D. so I don’t have a clue, although I would suspect it really wouldn’t make a difference.

Is there anyone here who is medically trained or experienced and knows the answer?

So I take it she doesnt really have any self control or what?

If she drinks alcohol, she’s going to have “irregular” enzyme levels and her LFT’s (Liver Function Tests) will be elevated and flagged. She should either reschedule her blood draw or stick to water, or it will be pointless.

It doesn’t sound like the labwork excuse is really going to work. If you want her to be sober during the intervention, you have to make sure she’s the last person to arrive and then begin immediately.

Thanks - I passed that along to her. Her question back: is 10 hours on fast really going to be bad, 12 OK? My response - I don’t know, but why not just have them reschedule? (my personal, ignorant suspicion is that they say 12 hours because that provides a buffer and 10 would probably be fine - but since I’m not a medical doc or technician, I’m not going to tell her that!)

Depends upon what she plans on doing in those extra 2 hours. Drink a few glasses of wine or perhaps one or two beers? Maybe. Drink any more than that, then no. She would do well to not drink alcohol 24 hours before the blood draw, really. Likewise, a full-ass meal, also not a good idea. It’s all about whether you really want honest test results or not.

I will ask an honest (but probably very stupid) question. What if you routinely drink fairly heavily? Wouldn’t you get an abnormal test result, versus your body’s ordinary state, if you stopped drinking?

Yes, I realize this would apply to food as well, which we eat all the time, yet they still tell us to fast.

As a confirmed drunk, the answer is yes. It’s not a stupid question. I was really surprised.

If you drank hard and heavily enough, you would get abnormal LFTs because of the damage to your liver. If you drank before the test, your LFTs would look even worse as a result of it.

See, when you drink alcohol, your liver processes the alcohol using a series of enzymes. These enzymes are released during the metabolism of alcohol. Now, constant damage to your liver by excessive alcohol not only causes liver cell destruction which releases liver enzymes due to cell breakage, but your body will work to try to keep up with the alcohol indulgence by synthesizing/releasing higher than normal liver enzymes to try to deal with the issue. The LFT test is sort of nonspecific, in that it checks for a variety of liver enzymes to a certain threshold blood concentration, mostly to indicate liver cell damage. alcohol is perfect for transiently mimicking this effect - it’s not the only thing, mind. Drugs both legal and illicit do too, but alcohol intake is much more common and very liver-specific.

Jesus, tell her to grow the fuck up and just not drink after 8. Is she that self centered and that much of a drunk that she can’t stop drinking for one night and just drink water?

I know you can’t tell her that exactly, but come on. Where does she live a frat house?

Which really sucks, because she is hosting a pre-superbowl party tonight, and she really would like to be able to drink a little later than 8:00 PM tonight.

Yes, obviously she’s a lush living at a frat house. Sheesh.

Ok, maybe that was a little judgemental, but come on. Does she really want to screw up her blood tests by having that extra drink? Why not stick to water after 8? Doesn’t seem worth it to me.

I had a friend who is a pilot. His company told him that he was not supposed to drink for 12 hours before a flight. When that 12 hour mark came, he stopped cold. In fact he’d taper it down before then, but he would not touch a drink after that time. Of course he could have gone “Ok, one more beer”, but that would defeat the spirit and letter of the rule.

I’m ordinarily in the same camp on these things that others are suggesting, but I think it’s a little strong on this one. Come on. She’s having probably a fairly routine test. The Super Bowl comes once a year. It may not be a big thing for you, but a lot of people really get up for it. She’s not suggesting that she has to drink or she’ll die, she’s just wondering whether enjoying an event that is either of interest or is important to her will really do any harm to the tests. I don’t see why that makes her some alcoholic whore or something.

What they are looking for in the blood test is 12 hours after normal behavior, not 12 hours after abnormal food and alcohol consumption. If she’s going to splurge before 8PM and then stop then she might as well just reschedule the test. If she wants to do the test, then she should probably take it easy at the part even before 8PM.

Got all the feedback, thanks. Yeah, since we’re in the Chicago area this Superbowl thing is pretty big and festive right now.

I’m not gonna get all judgmental on her - she’s not a lush, just having a bunch of friends over for a big Bears/Superbowl party tonight, and knowing her she’d probably have one gin and tonic per hour. She just asked me if it would mess up her results - she said cbc, cholesterol, and thyroid - if she had a drink after 8, if that 12 hours was just a “safety” margin to make sure everything was gone. She’s a big girl, I told her what you guys said and then told her to just call her doctor and ask.


One drink/hour ought to be fine, just not past 10PM at the very latest. If she’s not getting LFTs done, then the worry is largely decreased - although her cholesterol might be affected by drinking, it’s not likely that one G’n’T per hour will be enough to do it. CBC can sometimes be erratic but again, not likely with such low drinking. Thyroid is no sweat. However, still - no food!

The easiest thing would be to reschedule the test for next week. Is that like not an option?

We should fucking burn this tramp. HOW DARE SHE ENDANGER THE LIVES OF NO ONE WITH HER DRINKING!!!111!!!

A little judgemental? Dude you’re being a total dick. The lady is just asking if it will really screw things up that bad to have a couple glasses of wine and she’s a drunk living in a frat house?

I’m not sure, but I think that it’s called self control. Haven’t you people ever gone out and been the designated driver? Can we not have a good time without drinking anymore? I like it as much as the next guy, but if there is something important to be gained in avoidance (like an accurate blodo test, or being on medication), I can certainly moderate myself. I just don’t understand lack of self control. But it’s not my life, so like I said, maybe I came down too harsh. We’re in a society where no one can judge anyone else anymore and everything is relative, right?