# Can I drink black coffee before a fasting glucose/cholesterol blood draw? NEED ANSWER FAST **URL:** \ **Category:** In My Humble Opinion\ **Created:** [October 23, 2018, 1:33pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383 "2018-10-23T13:33:53Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [October 23, 2018, 1:33pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/1 "2018-10-23T13:33:53Z")
See query. Will be going to blood lab soon. Coffee’s basically water, right? ---
**Author:** ![GaryM](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garym/32/241_2.png) [@GaryM](https://boards.straightdope.com/u/GaryM)\ **Post date:** [October 23, 2018, 1:40pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/2 "2018-10-23T13:40:12Z")
I asked my doctor the same question a few years back and at that time I was told it was OK to consume black coffee or plain tea. But your doctors answer may not be the same. ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [October 23, 2018, 2:03pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/3 "2018-10-23T14:03:49Z")
Yep, I’ve always been allowed black, unsweetened coffee before a standard blood draw. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [October 23, 2018, 2:20pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/4 "2018-10-23T14:20:22Z")
Coffee’s basically water except that it isn’t. Most guidelines allow only water for 12 hours prior to fasting glucose draws, but cholesterol tests are less sensitive. Your doctor may also have ordered other tests that weren’t explained in detail. I would abstain unless absolutely necessary. ---
**Author:** ![Lucas\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lucas_jackson/32/303_2.png) [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Post date:** [October 23, 2018, 2:45pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/5 "2018-10-23T14:45:45Z")
My doc says no ---
**Author:** ![Athena](https://avatars.discourse-cdn.com/v4/letter/a/35a633/32.png) [@Athena](https://boards.straightdope.com/u/Athena)\ **Post date:** [October 23, 2018, 2:50pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/6 "2018-10-23T14:50:12Z")
In theory, yes. In practice, from all the various diabetes forums I frequent, a subset of people report blood glucose increases from black coffee. It doesn’t affect me, but to be safe, I’d avoid it before a blood draw. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [October 23, 2018, 2:56pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/7 "2018-10-23T14:56:54Z")
Medical advice is best suited to IMHO. You need to ask a medical professional about this, not people on an anonymous message board. Colibri General Questions Moderator ---
**Author:** ![Shoeless](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/shoeless/32/7099_2.png) [@Shoeless](https://boards.straightdope.com/u/Shoeless)\ **Post date:** [October 23, 2018, 3:03pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/8 "2018-10-23T15:03:18Z")
Plain coffee or tea (no milk, sugar, creamer, or other additives) should be fine. I do it all the time, and in fact when the lab lady asks me if I’ve had anything to eat or drink and I say “just coffee” she goes ahead and does the blood draw. If it was an issue I’m sure she’d let me know. Actually, I usually have to give a urine sample with my blood draw, so a couple of cups of coffee helps with that, if you know what I mean. 😉 ---
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [October 23, 2018, 5:09pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/9 "2018-10-23T17:09:54Z")
> [@Colibri](#): > > Medical advice is best suited to IMHO. You need to ask a medical professional about this, not people on an anonymous message board. > > Colibri > General Questions Moderator Yes you’re right. Sorry for the mispost. Also, thnx to all. In the meantime I got through to my endocrinologist’s nurse and got the ok. ---
**Author:** ![Living\_Well\_Is\_Best\_Revenge](https://avatars.discourse-cdn.com/v4/letter/l/6bbea6/32.png) [@Living\_Well\_Is\_Best\_Revenge](https://boards.straightdope.com/u/Living_Well_Is_Best_Revenge)\ **Post date:** [October 23, 2018, 5:24pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/10 "2018-10-23T17:24:51Z")
My doc says yes. ---
**Author:** ![dalej42](https://avatars.discourse-cdn.com/v4/letter/d/67e7ee/32.png) [@dalej42](https://boards.straightdope.com/u/dalej42)\ **Post date:** [October 23, 2018, 7:34pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/11 "2018-10-23T19:34:09Z")
I have always done that before my health exams. I only take my coffee black so it’s no hardship for me ---
**Author:** ![teela\_brown](https://avatars.discourse-cdn.com/v4/letter/t/d9b06d/32.png) [@teela\_brown](https://boards.straightdope.com/u/teela_brown)\ **Post date:** [October 23, 2018, 8:00pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/12 "2018-10-23T20:00:45Z")
I can only drink my coffee sweetened, so I have to wait. I bring a container of sweetened espresso with me, and as soon as the needle leaves my vein, I’m chugging it down. Then I’m eating my pre-purchased Sausage McMuffin as I drive in to work. I get up really early, so I’ve been waiting two or three hours past my usual coffee and breakfast hour. ---
**Author:** ![HMS\_Irruncible](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hms_irruncible/32/7394_2.png) [@HMS\_Irruncible](https://boards.straightdope.com/u/HMS_Irruncible)\ **Post date:** [October 23, 2018, 8:27pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/13 "2018-10-23T20:27:46Z")
Yes, no cream no sugar. So my doc always says. ---
**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\ **Post date:** [October 23, 2018, 9:35pm UTC](https://boards.straightdope.com/t/can-i-drink-black-coffee-before-a-fasting-glucose-cholesterol-blood-draw-need-answer-fast/823383/14 "2018-10-23T21:35:47Z")
My doctor has no problem with me drinking plain tea. (I don’t drink coffee.)