So what should I eat now?
The old adage "eat, not too much, mostly vegetables" still applies, but I enhance that for modernity by severely limiting processed foods.
Effect of gut microbiome modulation on muscle function and cognition
21–30 of 35 posts
Re: Effect of gut microbiome modulation on muscle function and cognition
#22> The prebiotic improves cognition (factor score versus placebo (β = −0.482; 95% CI,−0.813, −0.141; p = 0.014)) Always difficult to interpret the effect size of medical studies. Can an expert chime in here? What does this translate to in percentage terms, or number of standard deviations? How can we tell if this is a clinically meaningful delta? More broadly - why the obsession in medical papers with statistical sign…
Not an expert, but see table 3. They use CANTAB as the test of cognition. Scores range from 0 (worst) to 1 (best).
β = the standardized beta coefficient. You do a linear regression, where the cognition score is the dependent variable, and prebiotic status is an independent variable. The values are standardized first (x - mean)/(standard deviation). β is the slope of the regression line. They use the prebiotic group as the reference group.
Re: Effect of gut microbiome modulation on muscle function and cognition
#23> The prebiotic improves cognition (factor score versus placebo (β = −0.482; 95% CI,−0.813, −0.141; p = 0.014)) Always difficult to interpret the effect size of medical studies. Can an expert chime in here? What does this translate to in percentage terms, or number of standard deviations? How can we tell if this is a clinically meaningful delta? More broadly - why the obsession in medical papers with statistical sign…
Not expert in medical science.
Here's my understanding β is coefficient (slope) for the linear mixed model and 95% CI is the confidence interval for the coefficient. There are no effect sizes given, my guess is it's harder to calculate for linear mixed models when models gets complicated. It's not easy/useful to interpret from coefficient here.
Rather see Table 3 for mean and SD. The mean(SD) change for cognition for Treatment group was 0.40 (0.83) and for placebo was 0.19 (0.70). Linear mixed model showed this was significant when other factors held constant.
Re: Effect of gut microbiome modulation on muscle function and cognition
#24> The prebiotic improves cognition (factor score versus placebo (β = −0.482; 95% CI,−0.813, −0.141; p = 0.014)) Always difficult to interpret the effect size of medical studies. Can an expert chime in here? What does this translate to in percentage terms, or number of standard deviations? How can we tell if this is a clinically meaningful delta? More broadly - why the obsession in medical papers with statistical sign…
I'll chime in:
(β = −0.482; 95% CI, −0.813, −0.141; p = 0.014): The "β" represents the change in the factor score due to the prebiotic. A negative number here (-0.482) likely means that the prebiotic reduced some kind of negative score associated with poorer cognition, thus improving cognitive function. The "95% CI" stands for the 95% confidence interval, which is a range of values (-0.813 to -0.141) that likely contains the true effect size. The smaller this range, the more precise the estimate. The "p-value" (p = 0.014) tells us the probability that the observed results could have occurred by chance. A p-value of 0.014 means there's a 1.4% chance the results are due to random variation, which is low, so the results are considered statistically significant.
In simpler terms, that study found the prebiotic to significantly improve mental functions compared to not taking anything, with a high level of confidence that this result is not due to chance.
HOWEVER, when you look at the size of the study, it's unimpressive. A larger RCT will be needed. Also, it was a 'remote' study, so they could not measure muscle mass. Also, analyzing stool samples has serious limitations, as there are quite a few species that cannot be cultured (or identified).
Re: Effect of gut microbiome modulation on muscle function and cognition
#25the last time I looked at microbiome stuff, someone at Stanford tried to chop up all the microbes in poop and sequence all the RNA/DNA sequences they could collect from that soup. It amounted to several petabytes of data or something ridiculous. Has anyone come up w/ a better way of analysis?
That's mind boggling. Is this published anywhere?
not sure...the talk was at NEURIPS 2016
https://nips.cc/virtual/2016/invited-talk/6190
Re: Effect of gut microbiome modulation on muscle function and cognition
#26This was an interesting read. In essence, a randomised controlled trial looked at the effects of gut microbiome modulation on muscle function and cognition in older adults. Participants in the trail received either a prebiotic or a placebo. My takeaways: - The prebiotic improved cognitive function, but not muscle function, for members of the trial. - The gut microbiome composition changed in the prebiotic group, with…
> an increase in Bifidobacterium abundance. (Was not clear on a first read if that is necessarily always positive).
The total effect of a microbiome is not an additive function of the individual species. These species interact in highly complex ways. Some species might normally release factors that are detrimental to health, but their behaviour is suppressed by other species present in the flora. Therefore the individual species are not of therapeutic relevance; due to limitations in our understanding, each flora must be considered as a whole.
Re: Effect of gut microbiome modulation on muscle function and cognition
#27It is interesting that they achieved any positive results with prebiotics. The animal study evidence suggests that these are weak interventions compared to fecal microbiota transplant (FMT) from a young individual or flagellin immunization. Weak in the sense that they don't last long for one dose, whereas both FMT and flagellin immunization are essentially years-long to permanent effects, and also weak in the sense o…
What I remember about the microbiome: it's rather specific and we won't get one mix to suit us all. Ah yes, here:
> A significant proportion of the infant gut microbiome is considered to be acquired from the mother during and after birth. Thus begins a lifelong and dynamic relationship with microbes that has an enduring impact on host health. https://www.nature.com/articles/s41467-023-38694-0
Re: Effect of gut microbiome modulation on muscle function and cognition
#28> The prebiotic improves cognition (factor score versus placebo (β = −0.482; 95% CI,−0.813, −0.141; p = 0.014)) Always difficult to interpret the effect size of medical studies. Can an expert chime in here? What does this translate to in percentage terms, or number of standard deviations? How can we tell if this is a clinically meaningful delta? More broadly - why the obsession in medical papers with statistical sign…
I'll chime in: (β = −0.482; 95% CI, −0.813, −0.141; p = 0.014): The "β" represents the change in the factor score due to the prebiotic. A negative number here (-0.482) likely means that the prebiotic reduced some kind of negative score associated with poorer cognition, thus improving cognitive function. The "95% CI" stands for the 95% confidence interval, which is a range of values (-0.813 to -0.141) that likely cont…
That confidence interval seems large, no?
Re: Effect of gut microbiome modulation on muscle function and cognition
#29Earlier quoted context omitted.
I'll chime in: (β = −0.482; 95% CI, −0.813, −0.141; p = 0.014): The "β" represents the change in the factor score due to the prebiotic. A negative number here (-0.482) likely means that the prebiotic reduced some kind of negative score associated with poorer cognition, thus improving cognitive function. The "95% CI" stands for the 95% confidence interval, which is a range of values (-0.813 to -0.141) that likely cont…
That confidence interval seems large, no?
In such a limited RCT, yeah. It does.
Re: Effect of gut microbiome modulation on muscle function and cognition
#30Earlier quoted context omitted.
A diverse diet with lots of plants, vegetables and fiber. This doesn’t change that.
What about fermented food?
That’s probably good on balance, except for alcohol. But this article doesn’t meaningfully change this recommendation (it’s an extra pebble on a large mountain).