Lipid changes during rapid weight loss: the expected trajectory Writing it up because I had to work it out twice and would rather nobody else did.
Lipid changes during rapid weight keeps being re-asked here and I think that is because the answer is conditional and the conditions never travel with it.
Attempting to write the conditional version down properly. Corrections welcome and expected — I would like this to end up as a maintained page rather than a fifth thread.
I have been on both sides of the Lipid changes during rapid weight argument in this category within eighteen months, which should tell you how strong the evidence for either side is.
Repeat before acting is standard practice for an isolated abnormal result on most analytes, and it is standard for a reason.
The opening post is right about the mechanism and I think understates the practical bit.
Adding a small correction to the Lipid changes during rapid weight summary above rather than a disagreement with it. The substance holds; one of the figures is out by a factor that matters.
I read post #5 twice before replying, because I had assumed the opposite.
One caution on Lipid changes during rapid weight: everything above assumes the underlying documentation is what it claims to be. That assumption is doing real work and is rarely stated.
Post #5 answers the question as asked. The question underneath it is different.
Lipid changes during substantial weight loss are expected and their trajectory is not always monotonic. A single mid-course panel can be misleading.
Adding this to the thread rather than to the wiki, because I am not confident enough for the wiki.
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.
Lipid panel interpretation: total, LDL, HDL, triglycerides all on one panel. Reading them together is more informative than reading one value in isolation. An elevated triglyceride with low HDL is different from triglyceride elevation alone.
A trend needs at least three points to be a trend. Two points are a line and a line through noise is still a line.
Worth separating Lipid changes during rapid weight as a question about the compound from Lipid changes during rapid weight as a question about the documentation. They get answered by different people and only one of them is answerable here.
This follows post #10 rather than contradicting it.
Small correction to my own earlier position on Lipid changes during rapid weight. I had the units the wrong way round, which changes the conclusion by an order of magnitude and therefore changes it entirely.
Worth separating two things that post #12 runs together.
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.
Adding the boring version of Lipid changes during rapid weight, because the interesting version keeps getting posted and the boring one is usually right.
Check the ordinary explanations, in order, and stop when one of them accounts for what you are seeing. Most of the time the second one does.
On post #16 — agreed on the reasoning, with one qualification.
The confident answers on Lipid changes during rapid weight and the well-sourced answers are not the same answers, which is the most useful thing I have learned reading this category.
The arithmetic in post #18 is right; the assumption feeding it is the part to check.
Glycaemic markers integrate over different periods. A point glucose and a longer-term marker disagreeing is not a contradiction; it is two different questions.
The honest answer is that it depends, and here is what it depends on.
Answering the question post #16 raises rather than the one it answers.
Ask what decision the result would change before ordering it. A test whose result changes nothing is a test that generates worry rather than information.
That has held every time I have looked, which is not the same as always.
Post #17 describes the usual case. This is about the unusual one.
I disagree with the framing of Lipid changes during rapid weight above, and I think it is a substantive disagreement rather than a terminological one. Setting out why, so it can be checked.
The reasoning depends on an assumption that is doing a lot of work and is never stated. If the assumption holds, the conclusion follows. I do not think it holds generally.
Liver enzyme changes during rapid weight loss are commonly reported and have several possible explanations, which is exactly why they need clinical interpretation rather than forum interpretation.
If that is already documented somewhere, ignore me and link it.
Lipid changes during rapid weight is one of those subjects where the general answer and the answer for a specific case diverge, and the thread will go in circles until someone says which one is being asked for.
Glycaemic markers integrate over different periods. A point glucose and a longer-term marker disagreeing is not a contradiction; it is two different questions.
The useful distinction on Lipid changes during rapid weight is between what was measured and what was inferred from it. Both end up in the same sentence and only one of them has error bars.
What would change my mind on Lipid changes during rapid weight is a second dataset collected by someone with no stake in the first. Until then I hold it loosely and I would rather say so than pretend to more.
Clear enough that I do not think I have a follow-up, which is unusual.
Confirming post #25 from a second method, which matters more than confirming it from a second person.
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.
Where I have landed on Lipid changes during rapid weight, having got it wrong once in public: the direction is clear, the magnitude is not, and anyone quoting a precise magnitude has borrowed it from somewhere that did not measure it.