Greg from B12Oils has new data on selenium, which could interest anyone who uses it, or anyone who uses B12 - for which Se is an essential co-factor. I asked him if he would mind if I pasted what he emailed me here, & he said no. So here it is: It is not so much what you eat, but where it was grown that may be important. Thus, Australia, NZ, and UK have been exporting soil selenium for years now, and so much of the produce, and probably worse if it is "free-range", can be deficient in selenium. Thus, in the UK selenium intake in the population is only half the RDA, in NZ it is only one quarter. Data in Australia is varied. You need about 6 eggs, 1 lb of chicken, or lots of lamb to get your RDA. Tuna, ham and shrimp are better sources (and that is in the US where selenium levels are high). RDA is about 55 ug. Fish has 12-60/100 gm, meats 5-40, and eggs 9-40 per 100 g, in Australia, but it would be regional, and depend upon whether they are battery fed or free range (battery fed would likely have more). This was in 2002, so I would guess less now. I would switch [from lamb] to pork. And in a second email: Yes the selenium problem. This appears to be really bad in countries such as NZ, Britain, Ireland, Wales, Sweden, Norway, and many northern and eastern European countries. Curiously not around the Mediterranean (as far as I can tell). It would be a hoot if the so-called benefits of the Mediterranean diet were actually due to much higher selenium in their food. If you want to post it on PR, and mention that it was in discussions with me that is fine. If we can wipe out CFS/FM, then you and I will have done something useful for society. Only diabetes, AD, ASD, PD to work on next, all of which seem relatively simple. I find the selenium story fascinating because it would potentially represent one of the most powerful single nutrient deficiencies that there is, arguably as important as B12, but also it has a huge role to play in B12 cycling through its activity in making functional B2. FYI there is only about 40 years of selenium left to be mined in the world (according to a paper I found). Won't that be interesting. The level of selenium intake in the UK appears to be halving every 10 years, so it is a big problem. Se deficiency would also cause globesity, as too B2, iodine, or even molybdenum deficiency. Similarly they would all cause an increase in the rates of dementia. Unfortunately AD Australia seems completely oblivious to the fact. Similarly increase the rates of ASD. Se deficiency doesn't appear to much of a problem in the US where intake is way above the normal, which is why selenium supplementation studies haven't worked in the US, but yet have in the UK. For some reason the Cochrane reviews don't appear to take this into account. BTW in the past Greg has emphasised that brazil nuts don't, after all, contain the right type of Se - so are no use as sources of Se. Needless to say I can't answer questions on the above, as I'm just passing on someone else's research.