|Image 1: A tablespoon of olive oil is probably not enough to boost your testosterone levels, right? Probably not, at least not by 250%, I should say.|
Before we are eventually going to have a cup of gomchui tea, to evaluate if we can stand the taste so that we could ingest the 2-3 servings it would probably take to negate the negative effects of an occasional fatty slip on our diet, I will yet invite you to take yet a look at two studies from Saudi-Arabia, in which the researchers showed quite convincingly that vitamin D can actually have all those magical anti-obesity effects that it is hailed for, if... yeah, if you put the active calcitriol instead of its precursor cholicalciferol into the fatty chow of rodents. Sounds good? Well let's go, then!
- The increased secretion of noradrenaline and adrenaline (see figure 1 - top, right), as well as the downstream effect on the expression of uncoupling protein UCP-1 in BAT and the subsequent increase on thermogenesis should contribute to the "body recompositioning" effect of oleuropein, of which Oi-Kano et al. state that they will be particularly pronounced on a "high-fat diet, i.e., 30% fat diet" (Oi-Kano. 2012).The fact that humans have hardly any BAT is yet not the only problem, when it comes to the real-world significance of these results. With 10.3mg per rodent per day, i.e. 41mg/kg per day (human equivalent dose 6.68mg/kg), the "effective dose" of regular extra virgin olive oil would be unrealistically high, even if we base our estimate on the same (unpublished) data Oi-Kano et al. use in the discussion of their results and assume that there are 104 mg/kg oleuropein aglycone in extra virgin olive oil. The scientists do yet obviously believe that 5L of olive oil (80kg x 6.67mg/kg body weight divided by 104mg/L olive oil) would be a "normal dietary intake of extra virgin olive oil" - a statement that sounds even more laughable, when we use data from a study by Owen et al. which found that the oleuropein content of extra virgin olive oil ranges from 2.3 to 9.0mg/L (Owen. 2000), with higher levels of oleuropein in bitterer EVOOs (Gutiérrez-Rosales. 2003), or base our estimates on another study from Oi-Kano et al. in which they measured an oleuropein aglycone content of ~19mg/kg extra virgin olive oil (actually we would even hate to make up for the lower density of olive oil and divide that by 0.91 to convert it mg/L). And let's be honest in view of the sheer amount of studies investigating the beneficial effects of extra virgin olive oil in animals and humans, I doubt that a +250% testosterone boosting effect of "normal dietary intakes of extra virgin olive oil" could actually have remained unnoticed...It also remains to be seen if olive leaf extracts provide a better alternative. In 2008, Jemai et al. report that the Chemlali olive leaves they used in their rodent study, yielded 4.32 g oleuropein and 3.82g oleuropein aglycone per 100g dried leaves (Jemai. 2008). In view of the fact that the yield will necessarily depend on both the cultivar an the extraction method, you should thus make sure that any extract you buy has a standardized content of oleuropein / oleuropein aglycone. Moreover, if you are mainly interested in the better-established antioxidant, antiinflammatory, antiageing, anti-viral, anti-microbial, anti-cancer, anti-atherogenic and skin protectant effects of olive oil (cf. Omar. 2010), 5L /day are not necessary, anyway ;-)
Figure 2: Vicious cycle of childhood obesity (top); childhood obesity trends - state rates (data according to Childhood Obesity Action Network. 2009)After correlating these data with additional information about taste preferences, Lissner et al. found that all three aforementioned parameters, i.e. total TV consumption, watching TV during meals and having a TV in their room, were associated with profound (21-30%) increases in obesity risk.The actual novelty of these results is yet that all these TV watching behavior correlated (in most cases monotonously) with the propensity to eat sugary and/or fatty foods - and that despite the fact that the same kids who were eating nothing but chips and dingdongs, when they were sitting in front of the boob tube did not show similar preferences for fatty and sweet in the contextual different testing sessions all 1,696 kids had undergone. Figure 3: A few steps a day can go a long way (based on Ayabe. 2012)Tip: Take a WALK! The results of another recently conducted study, which found that 30 min of brisk walking at approximately 60% of maximum heart rate after a meal reduce post-prandial lipidemia in healthy normolipidemic men, only corroborates the importance of daily physical activity (standing for 45min did not make a difference, btw; cf. Miyashita. 2012). While we do have the stress right after launch, we don't have the "exercise" that would historically be associated with the latter - and as of late this is not just the case for white collar workers like me ;-)
- Active vitamin D does what vitamin D3 doesn't do, ameliorate the oxidative damage due to high fat diets. While the few vitamin D3 supplementation trials in rodents and humans were real non-starters, when it came to the purported effects of "everyone's darling vitamin" against diet induced obesity, diabetes, inflammation, etc. a group of Saudi Arabian researchers has just published the second of two papers within the past two months which deal with the effects of active vitamin D, aka calcitriol, on the diet induced damage in muscle and liver tissue (Alkharfy. 2012). The profound weight loss the animals in the HFD + calcitriol trials experienced in both trials (even the LFD control did gain some weight!), should yet remind you that there is a good reason that you can't buy calcitriol over-the-counter at your local GNC and better don't reach out to whatever other sources you may just have been thinking about!That said, it is still remarkable that in a mouse model of prostate and breast cancer, dietary vitamin D3 (cholecalciferol) and thrice weekly injections of calcitriol worked equally well (Swami. 2012), while the cholecalciferol from your average vitamin D supplement sucks, when it comes to the metabolic effects everyone is promising you, you would see if you just bumped your 25-OHD levels to whatever novel heights. At least in the case of the obese rodents, a possible reason could simply be that obesity prevents it's conversion. That this appears to be the case is something we have already discussed in the context of the defect in the enzymatic cascade in obese patients in a previous installment of "On Short Notice". And if it's not obesity that hinders vitamin D from doing its purported job, you still got my hypothetical rants about the exuberant phosphate intake from the average western diet and its negative impact on the conversion of cholecalciferol to calcitriol (see "Hypothesis: Does Vitamin D 'Deficiency' Protect Us From Phosphorus Overload?")
- Published in the July issue of the Journal of Agriculture and Food Chemistry a recent the study by Cha, Song, Kim and Pan shows quite conclusively that a tea that's brewed from Lingularia fischeri (gomchui) can decrease the activity of the fat-digesting enzymes in your gut and thus minimize the energy influx from free fatty acids.What's also intriguing about this research is that green tea, despite having the highest content of EGCG and thus theoretically the most potent lipase inhibitor of all the three beverages (green tea, coffee and gomchui tea) had - as soon as a certain dosage threshold of 2-3 servings was achieved, the least effect on on lipase activity in the digestion model the scientists used. If your goal is to ameliorate the potential weight gain right after a binge, gomchui or even a strong black coffee would probably be better choices than a cup of green tea.
Figure 6: The effect green tea extracts have on the synthesis (FAS), transport (CPT II) and oxidation (ACO) of fatty acids in the liver, depend on both EGCG and caffeine (Suigiura. 2012)
- Alkharfy KM, Al-Daghri NM, Ahmed M, Yakout SM. Effects of vitamin d treatment on skeletal muscle histology and ultrastructural changes in a rodent model. Molecules. 2012 Jul 31;17(8):9081-9.
- Alkharfy KM, Al-Daghri NM, Yakout SM, Ahmed M. Calcitriol Attenuates Weight-Related Systemic Inflammation and Ultrastructural Changes of the Liver in a Rodent Model. Basic Clin Pharmacol Toxicol. 2012 Aug 21.
- Ayabe M, Kumahara H, Morimura K, Sakane N, Ishii K, Tanaka H. Accumulation of Short Bouts of Non-Exercise Daily Physical Activity is Associated with Lower Visceral Fat in Japanese Female Adults. Int J Sports Med. 2012 Aug 17.
- Cha KH, Song DG, Kim SM, Pan CH. Inhibition of Gastrointestinal Lipolysis by Green Tea, Coffee, and Gomchui ( Ligularia fischeri ) Tea Polyphenols during Simulated Digestion. J Agric Food Chem. 2012 Jul 25;60(29):7152-7.
- Childhood Obesity Action Network. State Obesity Profiles, 2009. National Initiative for Children's Healthcare Quality, Child Policy Research Center, and Child and Adolescent Health Measurement Initiative. Retrieved 06/02/2010 from http://wwww.nschdata.org/content/07obesityreportcards.aspx.
- Gutiérrez-Rosales F, Ríos JJ, Gómez-Rey ML. Main polyphenols in the bitter taste of virgin olive oil. Structural confirmation by on-line high-performance liquid chromatography electrospray ionization mass spectrometry. J Agric Food Chem. 2003 Sep 24;51(20):6021-5.
- Jemai H, Bouaziz M, Fki I, El Feki A, Sayadi S. Hypolipidimic and antioxidant activities of oleuropein and its hydrolysis derivative-rich extracts from Chemlali olive leaves. Chem Biol Interact. 2008 Nov 25;176(2-3):88-98. Epub 2008 Sep 7.
- Lissner L, Lanfer A, Gwozdz W, Olafsdottir S, Eiben G, Moreno LA, Santaliestra-Pasías AM, Kovács E, Barba G, Loit HM, Kourides Y, Pala V, Pohlabeln H, De Henauw S, Buchecker K, Ahrens W, Reisch L. Television habits in relation to overweight, diet and taste preferences in European children: the IDEFICS study. Eur J Epidemiol. 2012 Aug 22.
- Oi-Kano Y, Kawada T,Watanabe T, Koyama F,Watanabe K, Senbongi R, et al. Extra virgin olive oil increases uncoupling protein 1 content in brown adipose tissue and enhances noradrenaline and adrenaline secretion in rats. J Nutr Biochem. 2007;18:685–92.
- Oi-Kano Y, Kawada T, Watanabe T, Koyama F, Watanabe K, Senbongi R, Iwai K. Oleuropein supplementation increases urinary noradrenaline and testicular testosterone levels and decreases plasma corticosterone level in rats fed high-protein diet. J Nutr Biochem. 2012 Aug 15.
- Omar SH. Oleuropein in olive and its pharmacological effects. Sci Pharm. 2010;78(2):133-54. Epub 2010 Apr 23.
- Owen RW, Giacosa A, Hull WE, Haubner R, Spiegelhalder B, Bartsh H. The antioxidant/anticancer potential of phenolic compounds isolated from olive oil, Europ. J. Cancer. 2000; 36:1235–1247.
- Sugiura C, Nishimatsu S, Moriyama T, Ozasa S, Kawada T, Sayama K. Catechins and Caffeine Inhibit Fat Accumulation in Mice through the Improvement of Hepatic Lipid Metabolism. J Obes. 2012;2012:520510.
- Zhu J, DeLuca HF. Vitamin D 25-hydroxylase - Four decades of searching, are we there yet? Arch Biochem Biophys. 2012 Jul 1;523(1):30-6