topic Re: What is the point of blood tests if you "prepare" in advance? in Wellness

What is the point of blood tests if you "prepare" in advance?

depglass — Fri, 16 Jun 2017 13:49:06 GMT

I have a few friends that do this to some degree, meaning eat well for a couple weeks before the tests. One of them is a pharmacist. What is the point? If you can't get accurate results you don't really know what you are doing wrong and what meds you probably should be on.

Re: What is the point of blood tests if you "prepare" in advance?

Lipstickdiva — Fri, 16 Jun 2017 13:51:52 GMT

I'm not sure how you can "prepare" for a blood test. If you have high cholestrol, a few days or even a few weeks of healthy eating isn't going to change your numbers that much is it?

My DH has to have his A1C done every 3 months. That test shows his average blood glucose readings over a 3 months period so eating good for 2 weeks out of that 3 months period is useless.

I'm just not sure how you can prepare for a blood test.

Re: What is the point of blood tests if you "prepare" in advance?

jaxs mom — Fri, 16 Jun 2017 13:57:27 GMT

@Lipstickdiva wrote:
I'm not sure how you can "prepare" for a blood test. If you have high cholestrol, a few days or even a few weeks of healthy eating isn't going to change your numbers that much is it?

My DH has to have his A1C done every 3 months. That test shows his average blood glucose readings over a 3 months period so eating good for 2 weeks out of that 3 months period is useless.

I'm just not sure how you can prepare for a blood test.

It does make a difference, which is why they tell you to fast before having your cholesterol tested.

Re: What is the point of blood tests if you "prepare" in advance?

Laura14 — Fri, 16 Jun 2017 14:09:41 GMT

My personal choice but I can control my cholesterol fairly well with good eating.

If I have been a bit bad or if my appointment falls around the holidays that year, "prepping" saves me a lecture and several "no thank yous" for offered medication.

I am not a fan of popping pills for anything except irreversible or unchangeable lifestyle needs or conditions.

As someone else said, it's not a huge number changer but if you're borderline, it can save you some time in the naughty corner when you go in plus you should be doing it anyway. And anything that reverts you back to better habits is a good thing.

Re: What is the point of blood tests if you "prepare" in advance?

Yardlie — Fri, 16 Jun 2017 14:19:31 GMT

All my doctor asks is for me to come in fasting for my annual lab work so that he can get an accurate reading of my cholesterol, etc. He told me that those tests basically show how you've been eating for the past few months, so you really can't trick them. Why anyone would want to try is beyond me. Isn't the idea of a physical or lab work to find out how healthy you actually are? Why try to fool the system into thinking that you are healthier than you really are? That's dangerous in my mind.

Re: What is the point of blood tests if you "prepare" in advance?

Tinkrbl44 — Fri, 16 Jun 2017 14:21:44 GMT

@depglass wrote:
I have a few friends that do this to some degree, meaning eat well for a couple weeks before the tests. One of them is a pharmacist. What is the point? If you can't get accurate results you don't really know what you are doing wrong and what meds you probably should be on.

@depglass

Boggles the mind that people do this ..... It's like cheating on a test, IMO ..... or misrepresenting yourself. I can picture a few posters prepping with a healthy diet, etc etc for a few weeks before the bloodwork is taken, having it done, and then downing a whole pint of ice cream that evening because "they don't have to be good anymore". It's lying to your doctor .... so why even bother to get checkups at all?

Re: What is the point of blood tests if you "prepare" in advance?

151949 — Fri, 16 Jun 2017 14:43:45 GMT

@Tinkrbl44 wrote:
@depglass wrote:
I have a few friends that do this to some degree, meaning eat well for a couple weeks before the tests. One of them is a pharmacist. What is the point? If you can't get accurate results you don't really know what you are doing wrong and what meds you probably should be on.
@depglass

Boggles the mind that people do this ..... It's like cheating on a test, IMO ..... or misrepresenting yourself. I can picture a few posters prepping with a healthy diet, etc etc for a few weeks before the bloodwork is taken, having it done, and then downing a whole pint of ice cream that evening because "they don't have to be good anymore". It's lying to your doctor .... so why even bother to get checkups at all?

Exactly right. I know many people who spend a week practically starving so they'll have a good fasting blood sugar - of course their A1c is awful, but they think they can pull the wool over their doctor's eyes. They aren't!You only hurt yourself when you lie to the doctor.

Re: What is the point of blood tests if you "prepare" in advance?

Nightowlz — Fri, 16 Jun 2017 15:24:29 GMT

You would have to eat well longer then a couple of weeks to make a difference on your labs. I just have mine done. It is what it is. My cholesterol went up because I was eating too much eggs, bacon & sausage so I had to cut back. They just need to have their labs done to see where they actually stand so then they know what they need to change.

Re: What is the point of blood tests if you "prepare" in advance?

noodleann — Fri, 16 Jun 2017 15:59:22 GMT

From what I've read about the A1C, it's not evenly weighted across the prior 3 months. It's weighted more heavily with the prior month, and then less so the farther you get from the time the test is done.

If true, that means that behaviors (diet, exercise, meds) that keep blood glucose in the low end of normal for the month prior to the test might help you get a better number if you otherwise aren't diligent about those variables. So be good for 4 weeks, and it will help.

I have no idea whether tests for lipids and liver and kidney function could be affected like this as well.

Re: What is the point of blood tests if you "prepare" in advance?

hckynut — Fri, 16 Jun 2017 16:30:18 GMT

@depglass

If it is a complete blood test, some numbers will not change enough to skew the results. Vitamin deficiency are generally going to still show this via the readings. Now if the "preparation" is months or a year?

I do agree with you that a person should want the most accurate results, not results that might satisfy their doctors. Accuracy and my interpretation of the numbers is all I will settle for with my blood results.

Let me decide, via a copy of the resulting numbers, if this is "normal" for me, I really am not interested in what is considered "normal" for the population in general. A majority of the population does not live my lifestyle and classifying by a group tells me little.

hckynut(john)

Re: What is the point of blood tests if you "prepare" in advance?

hckynut — Fri, 16 Jun 2017 16:49:32 GMT

@Lipstickdiva wrote:
I'm not sure how you can "prepare" for a blood test. If you have high cholestrol, a few days or even a few weeks of healthy eating isn't going to change your numbers that much is it?

My DH has to have his A1C done every 3 months. That test shows his average blood glucose readings over a 3 months period so eating good for 2 weeks out of that 3 months period is useless.

I'm just not sure how you can prepare for a blood test.

@Lipstickdiva

The time of day can change lipid readings as can food and drink. There is a reason that most discriminating doctors want to test lipids when a person has not eaten for X amount of hours.

I personally want the most precise numbers possible, not just a "close as in horseshoes" number. As far as blood sugar numbers, I am far from knowing near as much as a diabetic, but I have seen diabetics sent back home when the nurses saw their blood sugar numbers when checked before our Cardiac Rehab Classes.

There also was a reason that I had almost daily full blood draws during the 7+ years I was on blood thinners. The numbers changed daily from "too high" to "too low", and for no known reason. Again, close does not count when you are talking INR/ProTime readings, or for those that have to closely monitor specific blood readings.

hckynut(john)

Re: What is the point of blood tests if you "prepare" in advance?

Lipstickdiva — Fri, 16 Jun 2017 16:53:45 GMT

@hckynut, yes cholestrol numbers would change depending on if you fast or not. I forgot about that but white cell counts, red cell counts, etc. won't and I don't know about vitamin levels?

My DH is a diabetic. He tests his blood daily but when you do that, the reading is your blood glucose level at that moment in time. It will be affected by what you have eaten. But an A1C test is the measure of your BG readings over a 3 month period.

I know of someone who tested herself in the mornings and right before dinner and her daily readings were always good. Her A1C wasn't so great. She was eating meals and snacks that were driving up her readings but was never testing at the times her numbers were up so she thought she was good.

Re: What is the point of blood tests if you "prepare" in advance?

hckynut — Fri, 16 Jun 2017 17:06:20 GMT

@Nightowlz wrote:
You would have to eat well longer then a couple of weeks to make a difference on your labs.

Hi @Nightowlz,

That is not true with many blood readings, and blood lipid readings happen to be one of them. Many think their total cholesterol number is the panacea, it is not. A low total is a small part of the importance of lipid numbers. As I said in another post here, "there is a reason doctors prefer fasting pre lipid testing".

To me, the only one being hurt by trying to manipulate blood numbers, is the person who is having their blood tested. Makes no sense to me, but it is their choice.

hckynut(john)

Re: What is the point of blood tests if you "prepare" in advance?

SilleeMee — Fri, 16 Jun 2017 19:58:42 GMT

Eating habits won't change test results except for the ones that require fasting. What I would be concerned about is how supplements and drugs would affect my results...like certain vitamins that elevate liver or kidney test results, or any other test results for that matter.

Re: What is the point of blood tests if you "prepare" in advance?

Sooner — Sat, 17 Jun 2017 04:28:37 GMT

I always prepare! I drink a some water when I get up so it comes out easier! I tend to faint if it goes on too long!

Re: What is the point of blood tests if you "prepare" in advance?

chrystaltree — Sat, 17 Jun 2017 20:53:59 GMT

Weird but I think eating well for a few weeks won't chang anything. A pharmacist would know that. It might blood sugar that is just borderline high but it would not affect cholesterol or anything else. Meaning if a person has high lipids, tinkering with his diet for a couple of weeks might produce a minor change but it wouldn't bring it down to the normal range.

Re: What is the point of blood tests if you "prepare" in advance?

aubnwa01 — Sat, 17 Jun 2017 21:24:10 GMT

@Sooner wrote:
I always prepare! I drink a some water when I get up so it comes out easier! I tend to faint if it goes on too long!

I drink a LOT of water before I go in to have labs done. Both so that they can find a nice juicy vein & draw the blood they need easily & also, so I can do the pee in a jar stuff! Several years ago, I went in & had gone bathroom when I got up (which is my normal thing to do) before going to the office & I ended up sitting in the waiting room pounding down water, for over an hour so I could make enough to give them a sample. Since then, after I get up & go #1 in the AM, I do a constant downing of water until the lab tech calls my name to go back with them.

Re: What is the point of blood tests if you "prepare" in advance?

tends2dogs — Sun, 18 Jun 2017 14:08:00 GMT

The clinic I go to for my physicals never has me fast for cholesterol testing. They said if it is high, they will retest after a fast and compare. Mine isn't high and I have even had chips just before the blood draw........;0.

I go to a preventive clinic so they do things different than mainstream. For example, I have thermograms rather than mammograms.

Re: What is the point of blood tests if you "prepare" in advance?

Q4u — Sun, 18 Jun 2017 15:32:58 GMT

Interesting because I've never thought of my doctor and myself being in some kind of parent - child relationship where she would "lecture" me on my lab results. We're trying to work together to achieve good results but as everyone knows that doesn't happen every time. She's matter of fact and I then have new resolve to better my results. It's a constant renewal of determination so I don't become complacent.

My AIC's are good and pretty consistent but emotional and/or physical stress (as well as food) plays a huge part in those numbers. Cholesterol is harder for me but each day is a clean slate and I really try.... so far, so good. But no... I don't "prepare" in advance aside from fasting for 12 hours prior. Really don't see how you can....

Re: What is the point of blood tests if you "prepare" in advance?

Financialgrl — Sun, 18 Jun 2017 15:59:22 GMT

I am a cancer survivor who has to have blood drawn 4 times a year. One of those blood draws is for an A1C bc one of the cancer drugs I take can affect glucose and cholesterol readings but the other 3 tests are just normal ones I fast.

My blood is spot on however, when I have an A1C performed, it always shows higher sugar levels, whereas otherwise the other 3 times it shows lower readings and I don't try to bother to game them. As already discussed the A1C has the ability to more accurately reflect a longer period of how you are eating so it's absolutely possible for someone to "game" their blood results to a degree unless their doctors do quarterly A1Cs like Lipstick Diva said her husband has. For me, if any of the 3 regular blood draws shows an issue, we rerun again sooner to see if it could be an issue and as I've stated one of my 4 blood tests is always an A1C.