Does anyone have any knowledge of why this happens, and whether this is a beneficial effect for healthy, normal people? Could it affect cognitive performance?
Here is the study: http://www.ncbi.nlm.nih.gov/pubmed/8967461
asked byTnQ (695)
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on June 07, 2013
at 12:35 AM
A ketogenic diet increases the blood flow...Could it affect cognitive performance?
This study is about fasting, not ketogenic diet. The first two words of the abstract you linked are, "During starvation."
But let's assume that we can extrapolate these results to ketosis caused by diet. This study found (and other studies have found also) that when ketosis raises cerebral blood flow, the brain's oxygen consumption (an indicator of energy use) remains the same.
Given the unchanged energy use I don't see any reason to suppose based on this study and other ketosis blood flow studies that cognitive performance increases.
However, we know from other kinds of studies that ketosis can increase cognitive performance under certain conditions. And many people report that they feel mentally sharper when they are in elevated ketosis.
Could it affect cognitive performance?
In order to answer this question we have to look at cognitive tests, not measurements of blood flow.
Here are two examples of papers that answer your question.
on June 07, 2013
at 12:45 AM
Looking at it from an evolutionary perspective it makes some sense. When cave people went into ketosis food was likely very scarce and they need their brains more than ever to help them find food so the body produces ketones which by some mechanism bring more blood into the brain. I notice this also in my life, I get very lucid either when fasting or low carb. The problem is it doesnt last indefinitely at some point I always crash. I also notice when I eat more carbs I daydream and get lost in my head much easier. Ketosis can obviously be very beneficial but it's application for different people is very individual. Nothing a little n=1 experiment can't figure out.