Just came out of the BDNF rabbit hole. And then I see Teezer's comment.
The connection to BDNF is an interesting one. BDNF supports the survival of neurons and the growth of new ones (see wikipedia).
From a Framingham study: Serum Brain-Derived Neurotrophic Factor and the Risk for Dementia
"During follow-up, 140 participants developed dementia, 117 of whom had AD. Controlling for age and sex, each standard-deviation increment in BDNF was associated with a 33% lower risk for dementia and AD (P = .006 and P = .01, respectively) and these associations persisted after additional adjustments. Compared with the bottom quintile, BDNF levels in the top quintile were associated with less than half the risk for dementia and AD (hazard ratio, 0.49; 95%CI, 0.28–0.85; P = .01; and hazard ratio, 0.46; 95%CI, 0.24–0.86; P = .02, respectively)...Brain-derived neurotrophic factor genetic variants were not associated with AD risk.
"By stimulating glucose transport and mitochondrial biogenesis BDNF bolsters cellular bioenergetics and protects neurons against injury and disease. By acting in the brain and periphery, BDNF increases insulin sensitivity and parasympathetic tone. Genetic factors, a 'couch potato' lifestyle, and chronic stress impair BDNF signaling, and this may contribute to the pathogenesis of metabolic syndrome. Novel BDNF-focused interventions are being developed for obesity, diabetes, and neurological disorders."http://www.ncbi.nlm.nih.gov/pubmed/24361004
Increasing BDNF can ameliorate amyloid β-induced neuronal damage (in our mouse friends):http://www.ncbi.nlm.nih.gov/pubmed/24713151
And for my gal pals out there: "We found that progesterone does indeed elicit an increase in both BDNF protein and mRNA levels in the cerebral cortex."http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2693123/
I know some of you can't use progesterone, but don't despair. From wikipedia: "Similar to exercise, both intermittent fasting and calorie restriction induce the production of brain derived neurotrophic factor, which in turn is associated with neurogenesis in the hippocampus."
The last thing I looked at this morning has to do with effects of diet (small study on healthy men):
"Plasma BDNF decreased also by 27.8% in 6 h after a high-fat meal." (They used Calogen as a meal replacer. Doesn't mention if this was iso-caloric.)
And of course we know high sugar/insulin is never good: "Our results demonstrate for the first time that 6 h of intralipid/heparin infusion during hyperinsulinemic euglycemic clamp significantly decreased by 43% serum BDNF and by 35% plasma BDNF level."http://care.diabetesjournals.org/content/35/2/358.full
This high fat effect seems to contra-indicate a high-fat diet...JG, any ideas to explain this? Is overcoming dysfunctional glucose metabolism more important than the decrease in BDNF we might get from a high fat diet?
Anyway, it appears whatever we can do to increase BDNF is a good thing and our little gut friends are just another option.
Anyway, I know we have BDNF stuff scattered everywhere. I'll stuff it all together in a post, and someday a wiki.