3 ms·

The study you point to here is a guideline on conducting studies. It was unfortunately not available online so I can't evaluate their recommended methodology. L

The study you point to here is a guideline on conducting studies. It was unfortunately not available online so I can't evaluate their recommended methodology. Looking for actual studies that tried to do randomized feeding trials, I found "A randomized controlled-feeding trial based on the Dietary Guidelines for Americans on cardiometabolic health indexes"[1] as a top hit, which fortunately had the full text [2] available. Randomized controlled-feeding sounds good, let's check it out. After trudging through this for a bit I came to the meat of the methodology: > Participants were provided a daily meal checklist (Supplemental Figure 1) that included each menu item with space for documenting the amount consumed; the time each item was consumed; a checkbox to confirm having only eaten study foods; a checkbox to confirm not taking any medications, supplements, or other remedies; space for documenting any adverse events related to eating the meals; and space for documenting any nonstudy foods, drinks, medications, supplements, or other remedies. They were also instructed to return all unwashed packaging; visual inspection was documented by the metabolic kitchen. In addition to the checklists and returned packaging, participants were educated on food safety as well as provided tips on managing challenging social situations while participating in a feeding study. Repeated reinforcement of the value of honesty over perfection was provided. Study coordinators reviewed the returned checklists with the participants to verify completeness. So ... self reported with some extra steps. [1] https://pubmed.ncbi.nlm.nih.gov/30101333/ https://pubmed.ncbi.nlm.nih.gov/30101333/ [2] https://www.sciencedirect.com/science/article/pii/S0002916522029343?via%3Dihub https://www.sciencedirect.com/science/article/pii/S000291652...

llm_nerd 2y ago
I'm not sure what the intention of your comment is. Yes, I linked to the guidelines on feeding studies because that is entirely the point of my comment. You linked to a study where food was provided to the subjects (the food obviously nutritionally selected and provided per the study groups), and the subjects obviously are assumed to stick to the provided food and to accurate report what they ate among that reported food (with the study counting packaging, remainders, etc). This is a *UNIVERSE* better than the classic "tell us how many eggs you ate over the past two months" type nutrition studies, which are by far the most common (e.g. the Nurses' Health Survey). Are you expecting the people to be inprisoned? I mean, there are in-patient studies but they are obviously massively more difficult to carry out.
- andrewla 2y ago
  > Are you expecting the people to be inprisoned? I mean, there are in-patient studies but they are obviously massively more difficult to carry out. I expect rigorous methodologies to be employed before conclusions are drawn or held to be widely applicable. Self-reporting is intrinsically flawed. It does not seem like feeding studies as defined here addresses this or has been validated to produce superior results -- detected non-compliance was significant (though they did not report the difference between self-reported non-compliance and methodologically detected non-compliance) and undetected non-compliance was of course not measured. Would I expect to be only satisfied by imprisonment or inpatient studies? I don't even think I'd be satisfied by that! The differences in activity would make all such results difficult to interpret. But if inpatient is the best we can do, but it's difficult, then we have to live with the fact that our understanding of nutritional interventions is extremely dubious. You can't just accept bad science because it's the best you can do.

llm_nerd 2y ago

I'm not sure what the intention of your comment is. Yes, I linked to the guidelines on feeding studies because that is entirely the point of my comment. You linked to a study where food was provided to the subjects (the food obviously nutritionally selected and provided per the study groups), and the subjects obviously are assumed to stick to the provided food and to accurate report what they ate among that reported food (with the study counting packaging, remainders, etc). This is a *UNIVERSE* better than the classic "tell us how many eggs you ate over the past two months" type nutrition studies, which are by far the most common (e.g. the Nurses' Health Survey). Are you expecting the people to be inprisoned? I mean, there are in-patient studies but they are obviously massively more difficult to carry out.

andrewla 2y ago
> Are you expecting the people to be inprisoned? I mean, there are in-patient studies but they are obviously massively more difficult to carry out. I expect rigorous methodologies to be employed before conclusions are drawn or held to be widely applicable. Self-reporting is intrinsically flawed. It does not seem like feeding studies as defined here addresses this or has been validated to produce superior results -- detected non-compliance was significant (though they did not report the difference between self-reported non-compliance and methodologically detected non-compliance) and undetected non-compliance was of course not measured. Would I expect to be only satisfied by imprisonment or inpatient studies? I don't even think I'd be satisfied by that! The differences in activity would make all such results difficult to interpret. But if inpatient is the best we can do, but it's difficult, then we have to live with the fact that our understanding of nutritional interventions is extremely dubious. You can't just accept bad science because it's the best you can do.