Blood arsenic levels may be an accurate indicator of seafood intake
Image thanks to Joseph.
One of the difficulties in doing nutrition research is to try to accurately assess what people eat. Not what we say we eat, or not what we eat during a 3 day food record where someone basically follows us around with a clipboard, but what we actually eat, on average, when no ones looking. That’s why scientists love biomarkers, things you can actually physically measure in the blood or urine to tell you how much of a certain food someone is eating.
So, for example there are these unique phytonutrients in cruciferous vegetables like broccoli, kale, and collards that help prevent cancer, but you can’t just ask people if they eat their greens, because people want to look good and so they fib a little bit. Not any more, though, now there’s a urine test you can do to see if people are actually telling the truth. Some employers test for drugs; now you can test for greens—it’s like a broccoli breathalyzer.
The important thing is that now researchers can more accurately measure intake. Last year, scientists discovered a biomarker for fish consumption—like a tuna test. They take a sample of your blood and without asking you a single question about your diet can tell how much fish you’ve been eating. What’s the biomarker? Arsenic. Arsenic turned out to be the best indicator. Blood arsenic appears to be a useful biomarker for total fish and seafood intake.
To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring watch the above video. This is just an approximation of the audio contributed by veganmontreal.
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Please feel free to post any ask-the-doctor type questions here in the comments section and I’d be happy to try to answer them. And check out the sequel video on biomarkers for fish intake as well. Also, there are 1,449 other subjects covered in the rest of my videos--please feel free to explore them as well!
For more context, check out my associated blog post, Mercury Testing Recommended Before Pregnancy.


