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How accurate are blood tests?

fishboy9320

Senior Member
Messages
123
From my research 7 vitamin/mineral blood tests are inaccurate.

1. Vitamin D
''Two new blood tests for vitamin D are inaccurate in at least 40 percent of laboratory specimens analyzed, a new study finds''
2. B12 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3827408/
3. Magnesium because only one percent is in the blood
4. Calcium because it is stored in the bones
5. Iron You need a fasting blood level to get an accurate serum iron.” Ferritin levels can be falsely raised when a patient is unwell The results of tests of iron status are relatively frequently distorted by other clinical factors. This is important to recognise as such distorted results may give a misleading view of the patient's iron stores. The impact of these factors can be recognised by combining the results of currently available tests.
6. Thiamine (vitamin b1) Whole blood thiamine testing is superior to currently available alternative tests for assessing thiamine status. Serum or plasma thiamine testing suffers from poor sensitivity and specificity, and less than 10% of blood thiamine is contained in plasma. Transketolase determination, once considered the most reliable means of assessing thiamine status, is now considered an inadequate method. The transketolase method is an indirect assessment. Since transketolase activity requires thiamin, decreased transketolase activity is presumed to be due to the decrease of thiamin. However, the test is somewhat nonspecific, as other factors may decrease transketolase activity. Transketolase is less sensitive than liquid chromatography-tandem mass spectrometry (LC-MS/MS), has poor precision, and specimen stability concerns.
7. Biotin in blood or other samples taken from patients who are ingesting high levels of biotin in dietary supplements can cause clinically significant incorrect lab test results. The FDA has seen an increase in the number of reported adverse events, including one death, related to biotin interference with lab tests.4 Nov 2019
Some amount of vitamin B7/biotin can also be synthesized by the bacteria living in the gut like k2. So if you are deficient your gut bacteria is gonna be making more b7 and it is gonna be sent directly into the blood since it isnt stored so itwill perhaps interfer with lab results?

(EDIT) Found one more. From SelfHacked website:
Limitations and Other Tests
´´Vitamin E is fat-soluble, meaning that lipids must carry it through the bloodstream. High blood lipids (as in older or obese people) increase the amount of vitamin E in the blood but also hinder its transport into other tissues [8, 9, 10].

That’s why blood levels of vitamin E don’t always correlate with its intake and may not provide a clear picture of its status in your body. Experts suggest the ratio of alpha-tocopherol to cholesterol (or total lipids) is a more accurate indicator of vitamin E status [11, 12]. ´´ So it includes all fat soluble vitamins, K and A too?


Vitamin b1, b2 b6 etc are stored in small amounts in the body. B12 is stored in high amounts. Vitamin c is stored in brain some way.
 
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vision blue

Senior Member
Messages
1,877
No one test is perfect. My approach is to research the hell out of what i'm trying to figure out. Other people have approach of "treat the symptoms not the numbers".

if it's only 7 that are not up to par, that would be cause for celebration. I'd say it's more like 1007.

xcept for the first one on the new Vit D tests which i had not heard of, the others are old news and most are aware of them in some fashion or other If you want to take on the topic of inaccruacies in lab tests, surely you can do better... :)

Any particular reason you are interested in these 7 or this topic?
 

fishboy9320

Senior Member
Messages
123
The body has a limited capacity to store most of the B-group vitamins (except B12 and folate, which are stored in the liver).
 

Alvin2

The good news is patients don't die the bad news..
Messages
2,996
From what i understand they are typically accurate but you need to know how to interpret them. Which is what most of the text above is about, its not that the lab test is typically making analysis mistakes but that a snapshot from the blood does not necessarily tell you what you need to know.
Your vitamin D quote is surprising.
As for things like calcium it does so many things that levels in the blood are only measuring the levels in the blood. The body keeps this tightly regulated and steals calcium from the bones to keep the blood levels in the range it wants. Hence a blood test is not the bone status and you need the correct bone density test to check that.
If certain tests are measuring incorrectly because the technique is not good enough then its good to bear that in mind.
Also for most of the B vitamins the tests are not very useful, they are a snapshot, the body doesn't store them and they need constant daily replenishment. The blood tests may tell you something but are not very useful becasue in an hour or by tomorrow the blood level can be the opposite.
Vitamin E is a strange one, it seems it was dropped as a matter of concern, RDIs were never really determined, no doctor cares about the levels and deficiency is hard to measure becasue there is oddly not a lot of symptoms.
 

pamojja

Senior Member
Messages
2,384
Location
Austria
1. Vitamin D
''Two new blood tests for vitamin D are inaccurate in at least 40 percent of laboratory specimens analyzed, a new study finds''

What are the "Two new blood tests for vitamin D"? - what was the methology of this study? Could you post a link to this study please? Serum 25(OH)D3, the usual test for the storage form of vitamin C in serum and most frequently used, isn't by any means new. And does in my case highly correlate with intake, and depleting conditions over many years.
 

fishboy9320

Senior Member
Messages
123
From what i understand they are typically accurate but you need to know how to interpret them. Which is what most of the text above is about, its not that the lab test is typically making analysis mistakes but that a snapshot from the blood does not necessarily tell you what you need to know.
Your vitamin D quote is surprising.
As for things like calcium it does so many things that levels in the blood are only measuring the levels in the blood. The body keeps this tightly regulated and steals calcium from the bones to keep the blood levels in the range it wants. Hence a blood test is not the bone status and you need the correct bone density test to check that.
If certain tests are measuring incorrectly because the technique is not good enough then its good to bear that in mind.
Also for most of the B vitamins the tests are not very useful, they are a snapshot, the body doesn't store them and they need constant daily replenishment. The blood tests may tell you something but are not very useful becasue in an hour or by tomorrow the blood level can be the opposite.
Vitamin E is a strange one, it seems it was dropped as a matter of concern, RDIs were never really determined, no doctor cares about the levels and deficiency is hard to measure becasue there is oddly not a lot of symptoms.
All b vitamins are stored in the body to a lesser extent, its not as fluctuating as your making it ´´today high b vitamin, next day deficient´´. I have tested for vitamin D, magnesium, b12, folate and iron, and they came back normal but now I wonder if they might have not looked at it correctly or done the right test (using correct machine/equipment) because they are lacking experience/knowledge.
You can check for b vitamin defiencies by testing something that say requires b5 to be made or work properly. So if you have something thats depended on b5 and it is in a certain lower range even though your b5 lvls looks normal, that means you had been deficient before that for a long period of time.

I wanna test for all the b vitamins , vitamin e and a, iodine, zinc and vitamin C. I have an appointment with a new doctor and i dont know if i should bring up the fact that folate and b12 is stored in body for long periods of time so my blood tests is inaccurate. But folate is only 4 months and b12 5 years..
I wonder if your body senses definecies/urgency it slowly release its folate stores just enough to keep you alive but stil cause a lot of bad side effects because its not releasing enough bcus your not getting enough and its release is depended on the intake?

https://www.journalofhospitalmedici...26824/serum-and-red-blood-cell-folate-testing what is this
 
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Alvin2

The good news is patients don't die the bad news..
Messages
2,996
All b vitamins are stored in the body to a lesser extent, its not as fluctuating as your making it ´´today high b vitamin, next day deficient´´.
From, what i understand they are water soluble and not stored in appreciable amounts. Though appreciable does not mean zero

I have tested for vitamin D, magnesium, b12, folate and iron, and they came back normal but now I wonder if they might have not looked at it correctly or done the right test (using correct machine/equipment) because they are lacking experience.
There are several iron related tests, i am low/borderline in two but normal in some others.

You can check for b vitamin defiencies by testing something that say requires b5 to be made or work properly. So if you have something thats depended on b5 and it is in a certain lower range even though your b5 lvls looks normal, that means you had been deficient before that for a long period of time.
Indeed, though this can mean special requisition and is not typically done on a standard panel. Knowing what specific test to ask for is very important, i have had several never found until i had the right doctor ask the right question.

I wanna test for all the b vitamins , vitamin e and a, iodine, zinc and vitamin C. I have an appointment with a new doctor and i dont know if i should bring up the fact that folate and b12 is stored in body for long periods of time so my blood tests is inaccurate. But folate is only 4 months and b12 5 years..
Some docs like that you are well informed, some think your an alternative medicine basketcase and some are personally threatened. Also those numbers are not gospel, my B12 was very high so i stopped taking it, but since i am tested for other reasons they always tack on a b12 test i noticed mine drops about 1 point a day, so a very high reading off 1100 would be zero in 3 years. A normal say 600 would last less than 2 years for me.

I wonder if your body senses definecies/urgency it slowly release its folate stores just enough to keep you alive but stil cause a lot of bad side effects because its not releasing enough.
In some cases this is true, though i don't have any examples off the top of my head and i don't know if the ones you are interested in are true for this.
 

EddieB

Senior Member
Messages
604
Location
Northern southern California
5. Iron You need a fasting blood level to get an accurate serum iron.” Ferritin levels can be falsely raised when a patient is unwell
I myself am in a conundrum over this one. I have high (400) ferritin, low normal blood levels, none detected in bone marrow. The hematologists are baffled.

My new primary doctor is suspicious of this, and my negative sediment rate and C reactive tests as well. She says they are “too perfect” for someone with severe symptoms. At least she’s questioning things...

Tests are fine, but I think they can be a problem when doctors put too much trust in them, rather than listen to what we tell them.
 

fishboy9320

Senior Member
Messages
123
Its so frustrating nobody tests rest of the B vitamins or any other vitamins were I live just b12 and folate. And if they are low they go from there. Has anyone done a saliva or urine vitamin test are they more accurate?
 

Alvin2

The good news is patients don't die the bad news..
Messages
2,996
Its so frustrating nobody tests rest of the B vitamins or any other vitamins were I live just b12 and folate. And if they are low they go from there. Has anyone done a saliva or urine vitamin test are they more accurate?
As their levels fluctuate from meal to meal, hour by hour and day to day its often pointless to test them.
Take a high dose B complex and see if you feel better.
Now you might want to test if your body is absorbing them if you have some reason to think you have a genetic condition or some reason your body cannot absorb a specific nutrient.
 

fishboy9320

Senior Member
Messages
123
As their levels fluctuate from meal to meal, hour by hour and day to day its often pointless to test them.
Take a high dose B complex and see if you feel better.
Now you might want to test if your body is absorbing them if you have some reason to think you have a genetic condition or some reason your body cannot absorb a specific nutrient.
I have gut issues celiac and some other plus I could possibly lack a balanced diet. But I see what you mean for the normal person, but for someone like me with gut issues it could be helpful. Even if it fluctuates a lot throughout the day someone with celiac might have severe deficiency (severe measured by how long deficiency caused health issues rather than the current levels) after a meal. So maybe a good way to test it would be to eat meals before (not use supplements to test but food to make sure the whole digestion process is working correctly) and test multiple times to see if it goes up a lot or not. They should have no reason to be low for the average person so if there is sign of low levels then there is an issue if the diet is in check and you don't have any other diseases. They do offer other B vitamin prescriptions injectables so one wonders why they exist if they aren't tested for.
 
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Alvin2

The good news is patients don't die the bad news..
Messages
2,996
I have gut issues celiac and some other plus I could possibly lack a balanced diet. But I see what you mean for the normal person, but for someone like me with gut issues it could be helpful. Even if it fluctuates a lot throughout the day someone with celiac might have severe deficiency (severe measured by how long deficiency caused health issues rather than the current levels) after a meal. So maybe a good way to test it would be to eat meals before and test multiple times to see if it goes up a lot or not. They should have no reason to be low for the average person so if there is sign of low levels then there is an issue if the diet is in check and you don't have any other diseases. They do offer other B vitamin prescriptions injectables so one wonders why they exist if they aren't tested for.
If you think its necessary take a B complex every few hours for say 8 hours before the test then get a single test done. If the levels are high then your absorbing it, if not then you have a problem.
That said what deficiency symptoms are you having?
 

vision blue

Senior Member
Messages
1,877
For gut issues, the Comphrehebsive Stool Test can be very useful. For vitamins, you might like the Organic Acid Test (great plains lab), tho dont trust vit C since its always low. I have not found the test or vitamibn narkers eapecially useful but more useful is anino acid urine because levels of these and interMediates can point indirectly to certain vitamin and mineral deficiencies, and more usefully than measuring leveks directly where you cant tell whats actually in the tissue. With AA testing, you can spot blockages in pathways which can point to certain vitamins being deficient
 

fishboy9320

Senior Member
Messages
123
The relatively large proportion of the body sodium found in the skeleton, i.e. 25 per cent of the total body sodium, Sodium and calcium are both stored in the bone together.

The total body content of folate is estimated to be 15 to 30 mg; about half of this amount is stored in the liver and the remainder in blood and body tissues

blood tests are inaccurate because the body will always seek to keep a balanced level of everything in the blood at all times.

Roughly 98% of the potassium in your body is found in your cells. Of this, 80% is found in your muscle cells, while the other 20% can be found in your bones, liver and red blood cells.

Also Vitamin D is mostly in skin etc and bones and hair not in blood.
 
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Alvin2

The good news is patients don't die the bad news..
Messages
2,996
The relatively large proportion of the body sodium found in the skeleton, i.e. 25 per cent of the total body sodium, Sodium and calcium are both stored in the bone together.
Almost nobody has shortage of sodium in their diet.
 

fishboy9320

Senior Member
Messages
123
About 25 percent of the iron in the body is stored as ferritin, found in cells and circulates in the blood. The average adult male has about 1,000 mg (counteract testosterone side effects?) of stored iron (enough for about three years), whereas women on average have only about 300 mg (enough for about six months).
 

fishboy9320

Senior Member
Messages
123
This person had Vitamin D injection after scoring low vitamin D on a blood test and it showed even lower levels than before! This would mean that your body tries to keep a stable level of it in the blood based on how much is stored in the rest of the body. So the injected vitamin D gets immediately stored in the body until all the capacities are full then the blood levels starts and keeps rising because it doesn't need to use up the body stores anymore!
If you have any diseases or bad symptoms take care off the essentials first like nutrients, diet, lifestyle etc before going to doctor and taking drugs or operation!


 
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halcyon

Senior Member
Messages
2,482
5. Iron You need a fasting blood level to get an accurate serum iron.” Ferritin levels can be falsely raised when a patient is unwell The results of tests of iron status are relatively frequently distorted by other clinical factors. This is important to recognise as such distorted results may give a misleading view of the patient's iron stores. The impact of these factors can be recognised by combining the results of currently available tests.
Also, according to Quest Diagnostics:
Quest Diagnostics said:
Samples should be taken in the morning from patients in a fasting state, since iron values decrease by 30% during the course of the day and there can be significant interference from lipemia.
 

fishboy9320

Senior Member
Messages
123
A healthy adult body contains 15-20 mg of iodine, 70-80% of which is stored in the thyroid gland.

INTRODUCTION. Protein is a functionally important component at the molecular level of body composition. Protein mass in healthy adults is relatively large, representing 10.6 kg, or 15.1%, of body mass in the reference man (1).

The amount of essential fat differs between men and women, and is typically around 2-5% in men, and 10-13% in women. The healthy range of body fat for men is typically defined as 8-19%, while the healthy range for women is 21-33%.
 

fishboy9320

Senior Member
Messages
123
Potassium is mainly stored in body cells, including those of bones. However, the body only retains the amount needed to function properly at the moment. The body doesn't deposit potassium, as it does glucose, for future use. Instead, healthy kidneys flush out excess potassium, excreting it in urine.


Iodine is mostly concentrated in thyroid gland(2). A healthy adult body contains 15-20 mg of iodine, 70-80% of which is stored in the thyroid gland. But under stress if ceased to function the thyroid will freeze with those intact until health is improved then will be released .

calcium helps pain and fear. etc
 
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