Micronutrient status when intake falls substantially — a second dataset

Micronutrient status when intake falls substantially — a second dataset Writing it up because I had to work it out twice and would rather nobody else did.

Posting a small dataset on Micronutrient status. It is mine, it is uncontrolled, and the method is stated so it can be discounted appropriately.

What I would like is not agreement but a second dataset collected by someone with no stake in mine. If one exists I would rather read it than argue for this one.

Narrowing the opening post, because the general version has more than one answer.

The confident answers on Micronutrient status and the well-sourced answers are not the same answers, which is the most useful thing I have learned reading this category.

Repeat before acting is standard practice for an isolated abnormal result on most analytes, and it is standard for a reason.

Reference intervals are constructed to contain the central ninety-five per cent of a reference population, so one healthy person in twenty falls outside one by definition.

I am describing what is, rather than arguing for what should be.

Answering the question the opening post raises rather than the one it answers.

Two things can be true about Micronutrient status at once: the mechanism is plausible and the evidence for the size of the effect is thin. Most of the argument here is people defending the first against attacks on the second.

Glycaemic markers integrate over different periods. A point glucose and a longer-term marker disagreeing is not a contradiction; it is two different questions.

Noted, and thank you for writing it out rather than summarising it.

Building on post #5 rather than restating it.

Before the thread moves on from Micronutrient status — what is the sample size behind the claim? I am not being difficult; I have seen the same figure quoted from an n of four and from an n of four hundred.

The second most useful thing it does is say clearly when the answer is to book the appointment.

Following this. I have the same question and no better information than the first post.

Two questions I would want answered before drawing anything from the Micronutrient status data above: how were the cases selected, and what happened to the ones that dropped out.

Post #8 put the caveat in the right place and I want to underline it.

On Micronutrient status the community has more anecdote than the confidence in this thread implies, and I include my own contribution in that.

Time of day: some biomarkers vary across the day. Cortisol in the morning differs from cortisol in the evening. Comparing results from different times of day is comparing things that are not the same.

That is my reading. Someone else read the same page differently and was reasonable.

Reference intervals: constructed to contain the central 95% of a reference population, which means one in twenty healthy people falls outside one by definition. Add biological variation and analytical imprecision and the base rate of a meaningless flag is substantial.