I don’t know about color, but not drinking enough water DOES really make the blood viscous. It can get so bad that a phlebotomist can’t draw their blood. They have sent such people home to get hydrated and come back the next day to get their blood drawn.

I’m not a doctor.

I think the brighter red the blood the higher the iron, or it might be the reverse. I don’t remember right now. I’ll try to pay attention when I get my blood drawn. My blood does vary from red to much darker, and my iron sometimes is quite low and then up to normal levels again when I take a lot of iron. I am pretty sure viscosity is affected by iron levels also. Low iron more viscous. Maybe platelets and other clotting factors do also?

The chance you were dehydrated enough to affect your blood in any way is not likely if you didn’t feel thirsty. That sounds wrong to me. Like some old wives tale.

It might have something to do with fat and cholesterol content. High enough cholesterol in the blood maybe reduces the dark redness of blood. If your cholesterol and fats are very high you can sit the vile of blood for a few hours and watch the fat rise to the top supposedly as the blood separates.

What were you having tested? If it is iron, CBC, or lipids it will be interesting to know if any of them come back very low or high.

Too late to edit. I wanted to add that it is important to drink plenty of fluids, I just was doubting you actually were so dehydrated on a normal day. Staying hydrated does help ward of blood clots and is good for the body in general.

“blood thickness and color have nothing to do with how much water one drinks,”

As I mentioned before I don’t know about color, but I actually watched this lady’s blood being drawn. Before they could finish drawing it, her blood had started to coagulate and they couldn’t finish the draw. Being dehydrated CAN cause this problem, which is why they sent her home and told her to drink lots of water before she came back the next day.

@snowberry I would think It doesn’t take that long to rehydrate. Drink a glass of water and they could have tried again. Why did she have to wait a day and make the trip again?

I ain’t no professional, but I can say that added water to any solution will dilute the concentration of the solution. In this case, water is the solvent, and the solutes are all of the blood cells. So it makes sense that the color will be diluted as well.

@ShaChris23 Sorry for so many separate posts. If your urine is very yellow or dark it is a sign you are dehydrated. If it is light yellow or clear you can be pretty safe to say you are plenty hydrated. Our bodies hold onto the water if we need it, we pee out the rest. The more fluid we pee out the less concentrated and less densely colored our urine is.

Not really, no.

@JLeslie Thank you. No I was not that dehydrated, although I certainly should be drinking more water these days, been feeling a bit sluggish and tired. The test I was doing for this blood draw was for food intolerance, not for iron or lipids. =(

@ShaChris23 If I were you, I’d make sure to be drinking your 64oz a day of water, or more, and make sure you’re eating lots of greens (esp if you’re a female.)

That’s just a general way to be healthy in general. Sluggish and tired, can be lack of iron, I get that when I don’t eat enough veggies or eat too much frozen/ pkg foods (if you bruise easily, you may be iron deficient). Cut out salt, too, when you can.

@ShaChris23 Well, feeling sluggish can mean low iron! Hopefully, your doctor is doing a CBC along with the food tests. I have no idea what blood tests are run for food intolerance. Did you fast for the test?

Yes. I back @JLeslie on this one. What’s weird is phlebotinists don’t seem to know it. Or the ones I’ve encountered. They also appear not to know the difference between leather and skin or holding the needle in line with the vein rather then tapping at an abrupt angle down, grumble grumble.

But yeah I had ubit treatments done several years ago and were stopped because of my blood either being to runny or coagalating and stopping the line.

But blood draws are just the same. It’s been yrs since I have ever coagulated during one but I hate procedures that are npo because they either want to do an iv line take labs or open a portal and I remember one particularly bad one that took 5 different people took 15 stabs and digging. And they were actually talking about using my feet. Or me going home, and when they finally got it they couldn’t use the blood for labs because the vein or blood was responding to the trauma invalidating the results I forgot the name.

If you have a new injury in your arm the main vein in your arm may shut down and the blood be circulated through smaller ones. It took a couple years after a shoulder injury for them to use my right arm as anything but a last resort.

But don’t hydrate immediately before a blood draw there should be a half hour or so inbetween. Any time I seem to drink right before they say I have rolly veins and then some of them feel like it is perfectly acceptable to dig around and chase the vein. Which is very unpleasant.

The brightest you will ever see your blood is through an arterial blood draw. They took mine from my wrist and since they artery is well protected it is common to dig so they shoot your wrist full of a topical number. And wait 5 minutes and dig away. But it comes our crimson or scarlet.

Oh and since I was so awful by retaking you with worst case scenarios. Here are tips to a good blood draw.

Be well hydrated. Pump up your fist, by squeezing it into a fist and tensing the muscles. Clench unclench repeat right before hand. That way they might not put on the tourniquet so tightly. Relax your arm right before.

You’ll eventually learn which arm.has the better vein. Barring injuries its the strongest one. Actually if you are an easy draw I recommend using both arms and alternating. Veins scar up too and if its always used it becomes.slightly tougher and more resistent to the needle.

If you know the plebotonist is a brute or are nervous or don’t like blood draws ask for a butterfly needle it takes longer but it will help you get over the first stab and if there are multiple vials and they are using medication plunger or haven’t taped the port to your arm or the phlebotinist is effiecent but snappy in he/r movements the needle jostling won’t be so bad. It also works for when the phleb, holds the needle at sharp angle to your arm. They may also loosen the tourniquet mid draw to make it go faster.

After the draw or actually when they are setting up before hand they will ask if you are allergic to latex. Tell them you prefer the wrap around instead of the bandaid. These put pressure on the wound so you don’t have to which they recommend for ten min esp if prone to bruising, or if you are bleeding a lot that day.

If you’re dehydrated enough to coagulate blood, a simple cup of water won’t do it. It does take a while to rehydrate, and this old lady came in in the afternoon. She had to return the next day. She did so, and the blood draw went well. (I was there also).

No

Back to the OP. Sorry about the tangent. I did find this link that may be helpful to you. I would copy and paste but there is so much info in the link you might want to explore.

http://naturopathconnect.com/articles/thick-blood/

the constitution of blood is a very tightly regulated process. if you drink extra water, it will be very temporarily in the blood, just long enough for it to get to the kidneys to dump out. Most of the body’s fluids are in the cells, follow by the spaces between the cells (interstitial fluid), so when you dehydrate the blood pulls fluid from those spaces to get back to normal.
If you are severely dehydrated your blood will thicken, this is something that can be measured by blood tests. However it will show up in blood tests long before it is visible in the physical appearance of the blood. My druthers say that if you can see it physically in the blood, you probably look like death warmed over and are in the ICU. New onset diabetics sometimes come in looking that ill.
My only other thought about your blood is sometimes people have fast clotting blood (hypercoagulable), and will clot right in the needle or syringe as it’s being drawn. But I don’t think that should affect the color of the blood.

Thank you all for the tips! Darn, haven’t you all been ill! =)

Only up to a point. Then the kidneys kick in.

Oxygen will make the blood brighter. That’s why arterial blood is noticeably brighter than venous blood. When most people bleed, it’s usually dark red. If it’s bright red, you may be in big trouble. Heavy, or long-time smokers have darker blood as their lungs absorb less O2 because the surface of the aveoli are dirty and/or damaged and therefore unable to make the O2-CO2 exchange as efficiently.

Hydration will thin the blood which is one of the reasons why dehydration is dangerous. Aspirin thins the blood as well as St. John’s Wort.

Three things affect the oxygen content of blood: iron, copper, and vitamin E. But AFAIK the symptom is yellow skin, not dark blood. If you are going to have blood drawn, or plasma, according to my own experience, drinking a lot of water before you go in will cut the process to a few minutes instead of most of an hour.