Re: Rapeseed and soybean oils raise testosteroneOn May 12, 8:50 am, Taka <taka0...@gmail . com > wrote:
> I guess the common factor here is the Omega-6 linoleic acid. Taka
>
> Food Chem Toxicol. 2008 Jan;46(1):259-69. Epub 2007 Sep 11.
>
> Effects of dietary fats and proteins on rat testicular steroidogenic
> enzymes and serum testosterone levels.
>
> McVey MJ, Cooke GM, Curran IH, Chan HM, Kubow S, Lok E, Mehta R.
> Toxicology Research Division, Health Products and Foods Branch, Food
> Directorate, Health Canada, Sir Fredrick G. Banting Research Centre,
> 2202D1 Tunney's Pasture, Ottawa, ON, Canada K1A 0L2.
>
> It is known that certain dietary fats can modulate rat testosterone
> metabolism. In the current study we have investigated testicular
> steroidogenic enzyme activities and serum testosterone levels in rats
> fed diets containing either different protein sources (casein,
> fishmeal, whey) or different lipid sources (soybean oil,
> docosahexaenoic acid (DHA), seal oil, fish oil, lard). The diets
> examined reflect different marine oils and proteins which are
> significant components of Northern Canadian diets. Male rats (42-45
> days old, 6 per group), were assigned to specific diets for 42 days.
> On the 43rd day of the study, rats were sacrificed and blood plasma
> and testes frozen (-80 degrees C) until analysis. Microsomal
> steroidogenic enzyme activities (3beta-HSD, 17-OHase, C-17,20-lyase,
> 17beta-HSD) were measured radiometrically. There were no differences
> in enzyme activities between the three dietary protein sources. In
> contrast, compared with the standard casein diet, all lipid sources
> caused reductions in C-17,20-lyase activity (>50%); seal oil and fish
> oil reduced 17-OHase activity (approximately 30%) and soybean oil, DHA
> fish oil and lard reduced 17beta-HSD activity (approximately 30%). No
> effect on 3beta-HSD activity was evident. Serum testosterone levels
> were determined using ELISA kits and were not affected by any diet
> with the exception of the soybean oil diet which was significantly
> elevated compared with the casein protein diet. Body and testis
> weights were not affected by diet. In conclusion, these data
> demonstrate that some dietary lipid sources caused reductions in
> testicular 17-OHase and C-17,20-lyase activities but not to the extent
> that serum T levels were affected, while soybean oil caused elevated
> serum testosterone in the absence of elevated steroidogenic enzyme
> activities.
> PMID: 17936465
>
> Reprod Biol. 2002 Nov;2(3):277-93.
>
> Influence of dietary fatty acids composition, level of dietary fat and
> feeding period on some parameters of androgen metabolism in male rats.
>
> Gromadzka-Ostrowska J, Przepiórka M, Romanowicz K.
> Department of Dietetics and Functional Foods, Faculty of Human
> Nutrition and Consumer Sciences, Warsaw Agricultural University,
> Warsaw, Poland.
>
> The aim of the present study was to determine the effect of the
> composition of dietary fatty acids, the duration of feeding period and
> dietary fat level on androgen metabolism in male rats. One hundred and
> twelve Wistar rats were divided into 18 groups which were fed three
> diets containing different types of fat (rapeseed [R], palm [P] and
> fish [F] oil) at either normal fat level (w/w; 5%) or high fat level
> (20%) during one, three or six weeks. Blood plasma level of androgen
> (testosterone+dihydrotestosterone) and testicular activity of 17beta-
> hydroxysteroid dehydrogenase (17beta-HSD) were investigated. In
> addition, androgen content in cytosol of the heart, the target organ,
> was measured. Androgen concentration in both blood plasma and heart
> cytosol extracts was measured by radioimmunoassay. The activity of
> 17Beta-HSD was expressed as a conversion of [3H]androstendione to
> [3H]testosterone in soluble fraction of gonadal homogenates. Plasma
> androgen concentration was influenced by a type of dietary fat
> (p<0.05). The highest plasma level of androgen was observed in animals
> fed R diets rich in unsaturated fatty acids. Significantly lower
> androgen concentration was demonstrated in rats fed P diets rich in
> saturated fatty acids. Only the feeding period factor significantly
> influenced androgen content in cytosol fraction of heart muscle cells
> (p<0.01). A positive correlation was found between plasma androgen
> concentration in plasma and cytosol fraction of the heart muscle cells
> (r=0.63, p<0.001). The feeding period (p<0.001) and dietary fat type
> (p<0.05) significantly affected the activity of 17beta-HSD. The least
> 17beta-HSD activity was observed in animals consuming the P-20% diet
> for six weeks. In summary, dietary fat type and feeding period, but
> not fat level, significantly affected both testosterone production and
> testosterone uptake by the target organ in male rats. It was found
> that a rapeseed diet rich in unsaturated fatty acids stimulated the
> testicular function in rats.
> PMID: 14666150
I agree but soy is not healthy. New finds suggest that it is a poison.
Become a Fruitarian instead.
* what-is-a-fruitarian.blogspot . com /