Due to the sudden heat-wave over here in good old Germany I thought, I'd use these early morning hours to get another installment of "
On Short Notice" on it's way before my brain dries out (or I drown in the public swimming pool ;-). I hope you enjoy the four items on the
recent interest in intranasal the hormone modulating effects of oxytocin, it's effect on cortisol and progesterone, estradiol and (I know you were waiting for that ;-) testosterone, my early morning / late evening (depending on whether you see this from my or Wyatt's perspective) 'intellectual' exchange on the
potential longevity effects of exercise and why it probably is not life-extending in the literal sense, the
different antioxidant potency of green, black and white tea and their ability to chelate metals (=help to remove all not just "bad" metals from the body) and the
best fat, DHA or MUFA to blunt appetite and help you stick to your diet.
Don't forget to come back later today (or maybe early tomorrow for some of you ;-), for a third installment of "
On Short Notice", which will hopefully suffice to "get rid" of the stock I have... ah, I did not forget about the
Circadian Rhythm Series, by the way, it's just that the
SuppVersity rhythm got slightly out of sync ;-)
 |
| Figure 1: Effects of 26IU of intranasal oxytocin at rest on progesterone, estradiol and testosterone in healthy men (large; based on Gossen. 2012); effects of 24IU or 48IU of intranasal oxytocin administered before a steady state cardio session on cortisol levels in healthy young men (small; from Cardoso. 2012) |
Intranasal oxytocin to block cortisol & boost testosterone A whole series of studies has been published recently; all of them have one thing in common, they investigate the various physiological and psychological effects of oxytocin. Of these, the two studies by Gossen et al. and Cardoso et al. are yet probably of greatest interest for the average physical culturist. After all, the researchers from the Centre for Research in Human Development at the Concordia University in Quebec (Canada) were able to show that the administration of 24IU (not the higher dose of 48IU, though;see figure 1) effectively reduced the increase in cortisol in a 70% HRmax steady-state cardio session in 17 healthy young men (aged 18–3; mean ± SD; 23.1 ± 3.5), in the experiment they describe in their Aug 2012 paper in Psychoneuroendocrinology (Cardoso. 2012).And even though the German scientists from the
University of Aachen report minimal, but statistically significant increases in testosterone in 8 young men (mean age 26.4 ± 2.6 years) at rest, 210min after the (likewise) intranasal administration of a minimally higher dose (26IU) of oxytocin (Gossen. 2012). Both of these observations are not just very similar to what your average natty test booster is supposed to do, their real-world effects are probably also as insignificant. Also, did you ever try to tear down the gym and rep out a couple of PRs a couple of minutes after having sexual intercourse? If so, you should actually be aware why oxytocin probably ain't the ideal pre-workout supplement - in this regard it is also somewhat unfortunate that Cardoso et al. did not do a real performance test (suggested read: "
Will Sex Before A Competition Hamper Your Performance"; note: this is not about sex minutes before the competition ;-).
And when it comes to building muscle, previous research from Phillips lab at McMasters University appears to suggest that blocking cortisol is a hilarious idea, anyway. After tall, cortisol was the only endocrine hormone the elevation of which in the vicinity of resistance training sessions showed a positive correlation (r=0.29, P=0.03 cf. West. 2011) with increases in lean muscle mass in the large-scale by West et a.
- Exercise gets rid of the junk in your body, but will it help increase your lifespan? Basically this could be the headline to an interesting exchange of thoughts, I just had with Wyatt Brown on the SuppVersity facebook wall - one I believe is well worth being "recorded" as a short news item. The discussion came about in response to me posting the link to a study by He et al. who found that the way exercise induces autophagy (=natural, healthy cell death) contributes to its beneficial effects in the prevention of all sort of ailments, above all cancer and neurological problems such as Alzeimer's & co, because it allows your body to get rid of the debris and junk that's accumulating from just living your life (no matter how healthy or unhealthy that may be). Since exercise is not the only thing that can ramp up autophagy, and caloric restriction (as in starving yourself to live longer) can do the same, Wyatt mused about whether or not you could achieve the same (more or less; for animals vs. humans) proven benefits of life-long caloric restriction by exercise.
 |
| Image 2: Twin studies are one of the ways to identify whether genes or lifestyle are the fundamental determinants of how old we get. One of the consistent findings of the numerous pertinent studies is that lifestyle factors (diet, exercise, but also our outlook on life, friends and family!) determine how well we are able to use the time that our genes (or whoever you want) has granted us on earth. Not more, but not less, either: If 100 years are what we got, all exercise and healthy eating will allow us to make it to that age with great ease, not more... and let's be honest, if that was the biblical age of 100y, wouldn't it be ungrateful to ask for more? |
A very good question, indeed and one I do not have a definite answer to. In view of recent reviews of the role of exercise in the longevity of centenarians (the oldest of the old; cf. Venturelli. 2012), it does however seem more likely that exercise does
not have direct effects on the life-span, but, as Huffman states, "[e]pidemiologic evidence in humans supports exercise as a strategy to reduce the risk of morbidity and mortality" (Hufmann. 2010). Unfortunately, a low mortality won't help you to make it past the 100 ± X years your genes have in stock for you. The insights into the genetic determinants from pertinent studies into single-nucleotide polymorphisms (SNPs ~ single gene variations) does support this notion (Sorensen. 2012): The oldest of the old don't stick out, because their genes protect them from premature death, but simply because their genes allow for more cell cycles to occur before the 'natural reserve'. We already know that telomere length is a fundamental determinant of this 'reserve', so that it is not really surprising that
telomere length at birth is one of the most reliable predictors of longevity (Heidinger. 2012)!
Now, if we just use a totally random number to use basic math to make us understand, what this means, we could say that your telemore length at birth may be sufficient to make it to age 100, assuming that it is not prematurely shortened or you are dying from whatever other "natural" (not accidents etc.) cause, such as cancer, metabolic syndrome, CVD etc., exercise will of course help you to make it to those 100 years, but when the say 100,000 total turn overs that your telomeres allow for are done, you are done as well - no matter how "healthy" you eat and how much you exercise in the 99.99 years before. If you complement this "preventive" (=mortality reducing) effect by literally living on the slow lane, i.e. downregulating all your metabolic processes by starving yourself, you will obviously slow down the turn-over rate, as well. For simplicity of the calculation we assume that all these processes are linear (which I can guarantee they are not) and you are eating so little that you achieve a 50% slow down. That would mean that your turn-over rate would be reduced from 1,000 / year to 500 / year. Your reserves would last 2x longer and, assuming you eat and exercise and thus decrease your mortality risk, will allow you to make it to the ueber-biblical age of 200years! Great? Well you decide...
 |
| Image 3: If you want to get rid of metals, white tea should be your tea of choice, if you are already low on iron, copper, zinc & co. you should at least drink it away from your meals, though. |
Different tea preparations different effects antioxidant activity and metal chelation ability It is nothing new that green and black tea will have differential effects on your physiology. What is yet a novelty is a comparison of the antioxidant and metal chelating activity the exact same hand plucked leaves of a specific cultivar (in this case PC108, bred in Malawi, typically used for black CTC tea production) will have when it is used for the production of either white, two black (Orthodox and CTC; both methods produce leaves of fannings or dust grades that are commonly used in tea bags, CTC = crush + tear + curl is processed by machines, while orthodox usually involves a mixture of mashine and manual processing) or two green (w/ and w/out caffeine) teas - a comparison like the one Patricia Carloni and her colleagues present in their latest paper in Food Research International (Carloni. 2012).As you will probably have expected the least processed green tea exhibited the greatest, while the most processed CTC black tea the least antioxidant activity (green ≥ low-caffeine green > white ≥ black Orthodox > black CTC), what may come as a surprise though is the superiority of white tea in the metal chelation essay the scientists performed. Closely followed by the orthodox black tea, the CTC tea (<50% of the white tea metal chelating activity) and the two green teas (<25% of the white tea metal chelating activity).
 |
| Figure 2: Reduction in calorie intake on standardized breakfast 20min after the ingestion of 6ml of a lemon flavored oil emulsion and in the course of the day compared to no oil control (based on Harden. 2012) |
Fat satiety effects: DHA > Olive Oil (MUFA) > regular diet That would be the ranking according to the satiety effects of the different fatty acids, as elucidated in a recently published study in the British Journal of Nutrition (Harden. 2012). For their study, the researchers had recruited 18 healthy normal-weight men. In a single-blind, three-way crossover study design the subjects received a single 6ml dose of either DHA or oleic acid (olive oil is 60-80% oleic acid, alternatives would macadamia ~60% and high-oleic acid sunflower oil >82%) with lemon flavor. The day before, the subjects had consumed standardized diets. 20min after the ingestion of the emulsion, they had a standardized breakfast, went home and went about their regular daily business for the rest of the day. The telephone interviews the researchers conducted on the next day showed that the ingestion of the DHA emulsion had exerted an, as the researchers argue cholecystokinin (CCK) dependent, decrease in energy intake of -20% and -29% for the breakfast and the total daily energy intake, respectively. That would make DHA a pretty effective tool to stick to my often-suggested -20% caloric deficit when you're dieting - at least for healthy individuals. Whether this will work for the obese, let alone morbidly obese with their deranged satiety signaling remains to be seen, though.
As I mentioned in the introduction, already. This was not the last "
On Short Notice" item for this weekend. So, digest this, have some sex to calm down (unless you are about to work out, obviously), and drink a cup of tea to increase your chance to make sure that your end is not arriving before it's time and you can come back for more ;-)
References- Cardoso C, Ellenbogen MA, Orlando MA, Bacon SL, Joober R. Intranasal oxytocin attenuates the cortisol response to physical stress: A dose-response study. Psychoneuroendocrinology. 2012 Aug 10.
- Carloni P, Tianob L, Padellab L, Bacchettic T, Customud C, Kayd A, Damian E. Antioxidant activity of white, green and black tea obtained from the same tea cultivar. Food Research International. 2012.
- Gossen A, Hahn A, Westphal L, Prinz S, Schultz RT, Gründer G, Spreckelmeyer KN. Oxytocin plasma concentrations after single intranasal oxytocin administration - A study in healthy men. Neuropeptides. 2012 Aug 9.
- Harden CJ, Jones AN, MayaJimenez T, Barker ME, Hepburn NJ, Garaiova I, Plummer SF, Corfe BM. Effect of different longchain fatty acids on cholecystokinin release in vitro and energy intake in freeliving healthy males. British Journal of Nutrition. 2012; 108:755-758
- He C, Sumpter R Jr, Levine B. Exercise induces autophagy in peripheral tissues and in the brain. Autophagy. 2012 Oct 1;8(10).
- Heidinger BJ, Blount JD, Boner W, Griffiths K, Metcalfe NB, Monaghan P. Telomere length in early life predicts lifespan. Proc Natl Acad Sci U S A. 2012 Jan 31;109(5):1743-8. Epub 2012 Jan 9.
- Huffman DM. Exercise as a calorie restriction mimetic: implications for improving healthy aging and longevity. Interdiscip Top Gerontol. 2010;37:157-74. Epub 2010 Aug 10.
- Soerensen M. Genetic variation and human longevity. Dan Med J. 2012 May;59(5):B4454.
- Venturelli M, Schena F, Richardson RS. The role of exercise capacity in the health and longevity of centenarians. Maturitas. 2012 Aug 7.
- West DW, Phillips SM. Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training. Eur J Appl Physiol. 2012 Jul;112(7):2693-702. Epub 2011 Nov 22.
