Re: How to combine low fat, low sugar, low simple carbohydrates, low oxalate, low purine dietary recommendations. Food shopping. Portions preparations.

On Fri, 29 Dec 2006 09:28:13 +0200, "Juhana Harju"
<spamshantigiriorama.removespam@xxxxxxxxx> wrote:

Matti Narkia wrote:
: On Thu, 28 Dec 2006 20:56:37 +0200, "Juhana Harju"
: <spamshantigiriorama.removespam@xxxxxxxxx> wrote:
:
:: I agree with this guideline. Some healthy foods that the diet could
:: include are nuts, fatty fish, tofu, green leafy vegetables, carrots,
:: tomatoes, pomegranates, blueberries, red onions, olive oil, citrus
:: fruits, apples, and whole grains.
:
: Until the finding of the study
:
: White LR, Petrovitch H, Ross GW, Masaki K, Hardman J, Nelson J, Davis
: D, Markesbery W.
: Brain aging and midlife tofu consumption.
: J Am Coll Nutr. 2000 Apr;19(2):242-55.
: PMID: 10763906 [PubMed - indexed for MEDLINE]
: <http://www.jacn.org/cgi/content/full/19/2/242> (full text)

It should be noticed that there might be confounding factors affecting this
outcome. One such is the widespread vitamin B12 deficiency in vegetarian
subjects. The study neglected to measure this confounding factor. The
possible role of vitamin B12 has not even been discussed in the study which
is a clear omission.

The vitamin B12 factor seems unlikely in this context, IMHO. The
tested population was not known to be vegetarian, and the potential
effect of B12 of lack of it would probably have caused an inverse
association between at least some vitamin B12 rich food items and
cognitive impairment. However, the only food item for which
association with cognitive impairment was found, was tofu.

If the effect was real, one culprit could be soy isoflavones,
especially genistein. Genistein is an inhibitor of tyrosine kinase,
which is required for the induction of long-term potentiation (LTP) in
the brain's hippocampus, and genistein has indeed been found to block
LTP. LTP is change in brain cause by learning, and blocking it may
therefore have negative effects on cognition.

Brain-derived neurotrophic factor (BDNF) facilitates the survival and
genesis of brain cells. Soy appears to reduce BDNF in male rats, and
reduced BDNF can cause neural atrophy, these findings also appear to
provide evidence for a causal mechanism that might explain the
positive association between tofu consumption and brain atrophy
reported by White et al. But soy has also been shown to increase BDNF
in female rats, so in this light BDNF fails to explain the fact the
White et al. found among the wifes of the men in their cohort similar
association between tofu and brain aging. White et al. proposed that
in women long-term consumption of weaker soy estrogens may displace
the body?s own stronger estrogen along with its benefits.

Links:

Tofu and Brain Aging
<http://www.newswise.com/articles/view/?id=TOFU.NUT>

New Findings May Support
Soy-Dementia in Men
<http://users.erols.com/igoddard/soy.htm>

Too much tofu induces ?brain aging,' study shows
By Helen Altonn
Honolulu Star-Bulletin
<http://www.vegsource.com/harris/brain_aging.htm>


--
Matti Narkia
.

Relevant Pages
Quantcast