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question about drinking water prior to blood labs

I couldn't find a suitable category for this question but I hope to get some advise on this question. I recently had lab blood drawn for my hormones. It took 3 techs and 5 needle sticks before they got it accomplished all the while being "berated" for not drinking enough water. Now my family physician wants me to get blood labs done for my lipids. I was told to "fast" for it. I asked does that include water and was told only a small sip to get my routine meds down. Prior to my hormone labs I did indeed drink as much water as possible knowing everyone has a hard time getting to my veins. Now, I am told I cannot drink water for this lipid test. Is the limited amount of water so terribly important? What can I do with this problem that I have? I don't think I can stand to get stuck 3 more times again, much less 5!

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I've never heard anything about not drinking water affecting being able to get a good blood sample. Some people just have more prominent veins than others, and I believe it's genetic?

I would follow your Drs advice of fasting, if the phlebotomists complain refer them to your Drs advice, and consider complaining if they're giving you an especially hard time.

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Being dehydrated can absolutely affect a blood draw. If you're getting blood tests drink up!


You are incorrect. I too have this same problem. Its from dehydration. I've literally been given water to drink at my Dr. Office so they could draw my blood because they had tried 3 times and couldn't get it.


If your lipids (cholesterol) comes back 'high' write your story up on Thyroid Uk here on Health Unlocked, there is a high cholesterol low thyroid connection.

Years ago before thyroid bloods Doctors knew high cholesterol pointed to Low Thyroid (Hypothyroidism) They treated the thyroid with thyroid medication and the cholesterol level usually went back down to normal.

Do google - Low Thyroid and high cholesterol.

also google - 'The Great cholesterol con by Dr. Malcolm Kendrick'

Do NOT take dangerous statins.

Heart problems are now known to be caused by Statins, heart Doctors have been reporting low or normal cholesterol levels are causing heart attacks, rather than high cholesterol. Kidney failure and cataracts are also side effects of statins, my Mum had both, sadly now has to have kidney dialysis 3 times a week.


Fasting blood test:

Do not eat or drink anything except water for 8 to 10 hours before a fasting blood glucose test. These are used to diagnose diabetes, a condition caused by too much glucose (sugar) in the blood.

The above is for blood glucose. Now days there is another blood test, HbA1C.

Fasting blood test for cholesterol:

Blood cholesterol tests (lipid profile)

You may be asked not to eat anything and only drink water for 9 to 12 hours before having blood cholesterol tests (lipid profile).

There are several different cholesterol tests. When these are done together, it's called a lipid profile. A lipid profile tests the levels of:

•"good" (HDL) cholesterol

•"bad" (LDL) cholesterol

•total cholesterol

•triglycerides (other fatty substances)

If you're just having a triglycerides test, do not drink alcohol for 24 hours before the test (you'll also need to fast, as explained above).

An experienced blood technician can find blood collection point without any problems!


As a nurse who takes bloods regularly, moderately dehydrated patients can be difficult to bleed. But a morning 'fasting' bloods shouldn't be too difficult. If you're cholesterol is high, my advice would be to consider advice from a variety of sources. I have been on a Statin for twenty years due to an inherited condition, with absolutely no side effects but have my blood checked regularly anyway.


I'm so glad I posted my question about the water because all of you had such good advise. I plan to re-read them all and check into the information provided. Thanks again!!

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