Is there a blood test for this?

[Hazelip]

Is there a way to test one's blood and determine if meat has been consumed or not?'

I've been googling for a half hour, and I have been unable to find anything other than a fecal occult blood test.

Thanks for any assistance you may be able to to provide,
Jake

[Prester John]

Faecal occult blood (FOB), is used to determine if there is any blood in faeces, note occult means hidden, so this test is used to find non visible (ie small amounts) of blood in faeces. It is not of use for determing if someone has eaten meat.(its a very messy test apparently yuk!!).

The only thing i can think of is fats in blood. Not sure if there is a biochemical test, but blood plasma goes cloudy after eating a fatty meal (eg meat?).
Im not a biochemist btw so there may be something more useful, but its not a hospital required test (meat eaten)so i assume you would have to use a surogate marker.

[SteveGrenard]

What are you doing, looking for a way to make sure a vegan is telling the truth ...?


PS: Plants have proteins, and dairy products have proteins and fats.
Broken down it would quite complicated to
divine their constituents from similar ones in meat.

[Mr Manifesto]

The only thing I can think of as an indicator is a haemoglobin test which, fortunately, is painless (one pinprick) and takes all of about 1 second. You can probably get it done for free at your local blood bank.

Haemoglobin is somehow produced by the consumption of red meat. I forget how, though it was explained to me by a chick wearing a nurse's uniform who sounded like she knew what she was talking about. I also got a chart with all the foods that increase haemoglobin levels- vegetables can be good for iron, but still aren't much good for haemoglobin.

Lots of people with low haemoglobin are either vegetarians or only eat chicken/fish as meat.

However, this is only an indicator, not a 'hard and fast' test. There are other things that can cause low haemoglobin such as too much coffee and a rigorous athletic exercise routine.

When the subject of my low haemoglobin came up, we were able to eliminate one cause straight away. :(

[Rolfe]

I am a biochemist, and I'm still racking my brains on this one. For a start, how long would you want the answer to be valid for? Would a test that showed that no meat had been eaten in the previous 24 hours be sufficient, or do you want to prove vegetarianism over a long period?

Faecal occult blood probably wouldn't work. The human-only tests are specific for human haemoglobin, specifically to eliminate false positives due to consumption of meat. But for veterinary species we have to use the basic ones (there are no cat or dog haemoglobin kits), and although we usually advise feeding no red meat before taking a sample, to be quite honest I've had lots of negatives from dogs and cats on ordinary canned pet food. So, a positive would indicate either gut pathology, or yes, meat had been eaten, but a negative would mean nothing.

Measuring blood haemoglobin would prove nothing - even if vegetarians on average have lower haemoglobin than omnivores, the overlap between the groups is bound to be very large.

You can get a bit of lipaemia following a fatty meal, but that isn't guaranteed, and doesn't last very long anyway. And there are other causes of lipaemia.

I think there must be an answer to this, probably based on some sort of amino acid measurements, but there isn't an obvious simple test that I know of.

Rolfe.

[MRC_Hans]

Mmmm, there is an archaeological method of finding what type diet somebody (usually in skeleton form :eek: ) has been eating. Can distinguish between sea-food and other kinds of meat, and also, I think a predominantly vegetable diet. But I'm sure a single steak would not register.

What would be the purpose of this?

Hans

[sickstan]

Did anybody watch Autopsy Dead Cases special on HBO? On it, Dr. Baden performs an autopsy on a young man found dead in his house. He samples the stomach contents with a ladle and comments that there are pieces of meat in his stomach contents (ugh, I'm having reflexive nausea here). I would presume that if the meat had not passed into the duodenum, then you could sample it with a tube and have it examined by a pathologist. If it has been several hours, it may be nigh impossible to determine if the chyme has anything non-plant in it, because the pancreatic enzymes quite efficiently hydrolyze any remaining proteins that pepsin has not.

[Soapy Sam]

Perhaps a thorough dental examination would be the simplest way?

[Rolfe]

Yes, but how recent would the meat meal have to be? And Hazelip specified a blood test.

Maybe amino acids, or maybe fractionating the individual fatty acids would do it. You'd need to get a sizeable database of known meat-eaters and known vegetarians to validate the method though, if this hasn't already been done.

Rolfe.

[BTox]

Originally posted by Rolfe
I am a biochemist, and I'm still racking my brains on this one. For a start, how long would you want the answer to be valid for? Would a test that showed that no meat had been eaten in the previous 24 hours be sufficient, or do you want to prove vegetarianism over a long period?



Same here, I cannot think of any reliable method other than sampling stomach contents.

[Deetee]

The only other marker I can think of would be serum creatinine, which rises after meat consumption and tends to be 10-20% lower in vegans. However, its low specificity makes it unsuitable as a screening yes/no test.

[Phaycops]

You can use stable isotopes of carbon and nitrogen in hair (they did this to the iceman) to determine certain aspects of diet, but one would need to be a fairly strict vegetarian or meat-eater for it to show up. I remember my stable isotope prof telling us about an acquaintance of his that let his hair grow for a while and sampled it at different areas, corresponding to times when he lived in the US and Africa, and could easily see the effects of different diets on his hair isotopes.

I found this, on the website of Spectroscopy Now.com (website: http://www.spectroscopynow.com/Spy/basehtml/SpyH/1,1181,4-5-7-0-44635-ezine-0-2,00.html):

New research on the isotope analysis of the hair of living humans has now been carried out to study the relationship, if any, between diet and recent migration to another part of the world. Roland Bol of the Institute of Grassland and Environmental Research in Okehampton, UK and Christian Pflieger from Fachhochschule Jena in Germany measured the isotope values of local people from an English rural community and compared them with values for individuals who had recently arrived from Canada, Chile, Germany and the USA.

The results were revealed at the recent Annual Meeting of the Stable Isotope Mass Spectrometry Users' Group (SIMSUG 2002, see also SIMSUG 2003) and were published in Rapid Commun. Mass Spectrom. 2002, 16, 2195. Using the same isotopes (of carbon, nitrogen and sulphur) the diet and origin of the individuals was confirmed. So it was possible to identify an omnivore from the UK, as opposed to lacto-ovo-vegetarians and vegans.

Does this help?

[BTox]

Originally posted by Phaycops
You can use stable isotopes of carbon and nitrogen in hair (they did this to the iceman) to determine certain aspects of diet, but one would need to be a fairly strict vegetarian or meat-eater for it to show up. I remember my stable isotope prof telling us about an acquaintance of his that let his hair grow for a while and sampled it at different areas, corresponding to times when he lived in the US and Africa, and could easily see the effects of different diets on his hair isotopes.


This is interesting in that hair analysis for nutritional status is usually considered quackery, especially as used by diagnostic labs to show deficiencies in vitamins, minerals, and such.

[Hazelip]

Thank you all very much! A blood test was my first thought, but if another biological test (such as the hair test) could accomplish the task of determining if meat had been eaten, so be it.

The purpose? I'm an aspiring author of fantasy & science fiction. I'm currently working on a story in which Ingrid Newkirk is the head of a U.S. agency responsible for outlawing consumption of meat. If one travels abroad in this world I'm building, and re-enters the country with indications of meat consumption, there is a fine to be paid.

However, I do consider this to be an interesting question, fictional motivation or not. I've encountered several claims that vegetarians are healthier on average than meat-eaters; yet if it proves to be so difficult to distinguish one type of person from another, how can there be a valid basis for the claims? Meanings, if I cannot actually test someone the consumption of meat, how can I ensure that all the “vegetarians” tested do, in fact, abstain from consuming meat?

I'm looking forward to reading more suggestions. This question has been eating at me for days now. ;)

[BTox]

Originally posted by Hazelip
The purpose? I'm an aspiring author of fantasy & science fiction. I'm currently working on a story in which Ingrid Newkirk is the head of a U.S. agency responsible for outlawing consumption of meat. If one travels abroad in this world I'm building, and re-enters the country with indications of meat consumption, there is a fine to be paid.

I have to ask the question: why would a U.S. agency outlaw consumption of meat? From a health, economic and regulatory standpoint this is ridiculously implausible.

Originally posted by Hazelip
However, I do consider this to be an interesting question, fictional motivation or not. I've encountered several claims that vegetarians are healthier on average than meat-eaters; yet if it proves to be so difficult to distinguish one type of person from another, how can there be a valid basis for the claims?

I've seen no credible evidence that vegetarians are any healthier than those on any other well-balanced, meat-containing diet.

[Rolfe]

Originally posted by Hazelip
The purpose? I'm an aspiring author of fantasy & science fiction. I'm currently working on a story ....Oh, that's easy then. It only has to sound moderately plausible, which is a lot easier than actually working.

Just invent an "amino acid screen" or "fatty acid screen", and I'll guarantee that very few of your readers will be in a position to challenge the idea.

Rolfe.

[Phaycops]

Originally posted by BTox


This is interesting in that hair analysis for nutritional status is usually considered quackery, especially as used by diagnostic labs to show deficiencies in vitamins, minerals, and such.

Well, yes, but this is different for many reasons. First and foremost, nobody is using these hair analyses to diagnose, treat, or cure any disease. The only thing it's useful for is telling you what kind of diet someone ate. This has to do with the ways that different plants fix nitrogen. C3 and C4 plants have very different nitrogen isotope signatures, and this difference is consequently moved up the food chain, with a subsequent change to the isotope ratios at each level. Therefore, a strict vegetarian living off corn would have a much different isotopic signature in his/her hair than someone on the Atkins diet. There are also characteristic differences between marine ecosystems and terrestrial ecosystems in terms of nitrogen isotope values, so it is possible to differentiate between a population of Inuits who eat seal, and a population of people with a land-based diet.

Moreoever, you can see differences in one individual over the length of time their hair has been growing, because the residence times (don't know if that's the proper term, but you dig what I'm sayin') of nitrogen in the human body are very short. You can also examine the nirtogen and carbon isotopes of bone collagen or other organs and tissues, which all have diferent turnoever times. The valuable implications of hair are that you can get a record over several years of a person's life, if they've allowed their hair to grow that long. This has implications for anthropology and archaeology, and can also be used on animals.

Here's some websites for you to peruse:
http://wwwrcamnl.wr.usgs.gov/isoig/projects/fingernails/foodweb/isotopes.html

http://www.mankato.msus.edu/emuseum/biology/forensics/diet_and_dentition.html

http://www.staff.brad.ac.uk/mprichar/PRGIntrotoIsotopes.html

http://masseynews.massey.ac.nz/2002/masseynews/April/April29/stories/cow_hair2.html

http://www.findarticles.com/cf_0/m1200/1998_Nov_7/53280921/print.jhtml

[Hazelip]

Originally posted by BTox
I have to ask the question: why would a U.S. agency outlaw consumption of meat? From a health, economic and regulatory standpoint this is ridiculously implausible.It's FICTION... I've seen no credible evidence that vegetarians are any healthier than those on any other well-balanced, meat-containing diet. I didn't say that there was. I'd only said that I'd heard references, or claims.

Now, from a testing and authentication standpoint, I'm very curious. If there is no way to test, and therefore distinguish, a meat-eater from a vegetarian, how can anyone make any dietary claims? You'd only be taking the word of the test subject as to dietary habits.

[BTox]

Originally posted by Hazelip
It's FICTION....

I realize that. No offense intended, I also dabble in writing sci-fi, but as a scientist, I try to stay in the realm of plausibility. Just me, I guess.

[jj]

Originally posted by Hazelip
It's FICTION... I didn't say that there was. I'd only said that I'd heard references, or claims.

Fiction indeed. Ever read "Lipidleggin'" by, I think, Asimov, although it's been a long time since I read it?

Now, from a testing and authentication standpoint, I'm very curious. If there is no way to test, and therefore distinguish, a meat-eater from a vegetarian, how can anyone make any dietary claims? You'd only be taking the word of the test subject as to dietary habits.

Well, if we can make human-hemoglobin specific occult tests, perhaps we could make cow-specific, pig-specific, and bird-specific tests as well?

Perhaps detect residual cow/pig/bird/etc proteins in the system, probably not in the blood, though.

[SteveGrenard]

B12 levels can be analyzed by radioimmunoassay (RIA) and other methods. There is definitely a deficiency in non-supplement using vegans (strict, non-egg and dairy eating) of this vitamin. See the following Nutrition Council position website:

http://www.nadadventist.org/hm/gcnc/vitb12/vitb12.html

[bug_girl]

Originally posted by MRC_Hans
Mmmm, there is an archaeological method of finding what type diet somebody (usually in skeleton form) has been eating. Can distinguish between sea-food and other kinds of meat, and also, I think a predominantly vegetable diet.

wasn't that done through coprolites?
(i.e, fossilized poop.)
i know that's how they found the "first" case of human giardia, and also id'ed diet components of a lot of early europeans.

[Hazelip]

Originally posted by BTox
I realize that. No offense intended, I also dabble in writing sci-fi, but as a scientist, I try to stay in the realm of plausibility. Just me, I guess. Ah, well... Just read this older blog entry of mine, and I think you might see just what nerve you happened to strike. http://www.hazelip.com/2003_07_01_OldBlogs.html#105927397348181231

Sorry about that.

[Hazelip]

Originally posted by jj
Fiction indeed. Ever read "Lipidleggin'" by, I think, Asimov, although it's been a long time since I read it?Can't say that I have, and Google gives me nada. Can you explain?

[jj]

Originally posted by Hazelip
Can't say that I have, and Google gives me nada. Can you explain?

Lipidleggin' was a story about how fat was illegal, and people were executed for eating butter, making butter, selling beef, etc.

It was LONG time ago I read it.

I'm sorry, I THINK it was Asimov, it was a short story, and that's about all I recall.

JJ

[The Don]

Just a thought,

Could the meat be bioengineered to contain a marker chemical which could show up in a test to look at amino acids and so forth ?

Of course the carnivores would then go off in search of animals which do not contain these markers and make them part of the food chain (humans for example)

[Rolfe]

That woman described on the blog site was a complete nut. She thinks SF readers believe what they read? I read a lot of SF, and socialise with others who do, and they're the most critical thinking guys I know.

I think reading SF actually makes one more likely to be able to separate fact from fantasy, not less.

Rolfe.

[Phaycops]

Originally posted by bug_girl


wasn't that done through coprolites?
(i.e, fossilized poop.)
i know that's how they found the "first" case of human giardia, and also id'ed diet components of a lot of early europeans.

Could be bone collagen stable isotopes, too.

For example (From PubMed):

Schoeninger MJ, DeNiro MJ, Tauber H. (1983); Stable nitrogen isotope ratios of bone collagen reflect marine and terrestrial components of prehistoric human diet. Science, 220(4604):1381-3.


Abstract:
The delta 15N values of bone collagen from Eskimos and from Northwest Coast Indians dependent on salmon fishing are about 10 per mil more positive than those from agriculturalists in historic times. Among prehistoric humans, two groups dependent on marine food sources show bone collagen delta 15N values that are 4 to 6 per mil more positive than those from two agricultural groups. The nitrogen isotope ratios of bone collagen from prehistoric inhabitants of the Bahamas are anomalously low for reasons that relate to the biogeochemical cycle of nitrogen in coral reefs.

[Soapy Sam]

Rolfe- I agree about SF readers tending to the sceptical. I never met a serious SF reader (or writer) yet who took UFOs seriously , for example. I think to enjoy SF you require both willing suspension of disbelief and some understanding of where the real science falls away and the story science kicks in. The best writers make that transition either very hard to spot, or irrelevant due to clever use of plot and character.

I have shadowy memories of an SF short which featured a prohibition-like USA in which fresh bread could only be found in speakeasies. Can't recall the author. Must be thirty years ago.

[Rolfe]

Originally posted by Soapy Sam
I never met a serious SF reader (or writer) yet who took UFOs seriously , for example.I think when you figure about the distances involved in intersteller travel, and the time it would take, and that maybe it really is impossible to travel faster than light, and the whole time dilation thing, you realise that virtually every story has to find a way round this even to get started. Warp speed, jump gates, wormholes, whatever. Great for fiction, ain't likely to happen any time soon.

I think only Ursula Le Guin doesn't mess with the "light barrier", and her stories wouldn't get off the ground at all without the ansible. Have you read "Semley's Necklace"?

And then there's the whole evolutionary thing - if it's so all-fired improbable that life got going here, what's the chances of a similar improbability happening all over the place? How many times are these monkeys going to manage to type out the complete works of Shakespeare?

Relax and enjoy the story.

Rolfe.