Stronger & Leaner or Fatter & Less Muscular W/ 4,000IU Vitamin D3 - What if Abstract and Data Tell Different Stories?
SuppVersity Science Roundup on SHR, that hitherto trial after trial with supplemental vitamin D in the form of cholecalciferol (vitamin D3) failed to produce the desired results. And what do I have to tell you today? A group of researchers from the Purdue University and the College of Charleston have just published a study that appears to make it necessary for me, to at least rectify the previous assessment by stating: "With the exception of a recent trial from the Purdue University ..." Upon having a closer look at the actual data, it did yet turn out that the gap between what the abstract, on the one hand, and the real data, on the other hand, is about as wide as the still existent divide between the purported benefits from vitamin D supplementation and the real-world outcomes of respective trials.
It sounds as if Carillo et al. had finally done, what no one else has done before them, ...
Serious training + serious nutrition = serious gains... but what about vitamin D?
Moreover, with the additional protein shake (360 kcal; 8 g fat, 54 g carbohydrate, 20 g milk protein isolate, 100IU vitamin D and 300mg of calcium) every participant had to consume during the hour following the exercise sessions, the scientists rightfully call their experimental protocol "anabolic". It is thus no wonder that aside from ostensible weight loss and strength gain, both of which you would expect in formerly sedentary subjects, the subjects in both groups did also increase their lean mass (see figure 2, right) .
Vitamin D3 a "Fat Synthesizer"!? Rodent Study Shows +33% Increased Fat Deposition in Vitamin D3 Supplemented Mice.")
"Something is rotten is rotten, here, and I can tell you Horatio heaven did not direct it"*
"But it does make you stronger!" - Nope, that's another trick!
The latter is all the more true, because the participants in the vitamin D arm of the study may have increased their peak power faster (see figure 3), but the did not increase their overall strength on any of the exercises to a greater extend than the men and women in the placebo arm of the study.
The notion that this was the case, is simply a consequence of selective reporting (or in this case "highlighting") of study outcomes (cf. Chan. 2004); or, in other words, we are (mis-)lead by the overemphasis Carrillo et al. put on
the early (first 4-weeks) increase in peak power, and their
corresponding nonchalant surreptitious reference to the fact that "[n]o other improvements were observed with supplementation" (Carillo. 2012). In short, there is a ballyhooed increase in "peak strength" in the early weeks, but this does not change the fact that the participants in the vitamin D3 arm of the study ended up gained more fat and less muscle, and were - at the end of the trial - neither stronger nor leaner (neither in terms of their body fat %, nor in terms of their waist-to-hip ratio, which was not associated with supplementation!)
From a mere statistical perspective, you could even argue that nothing happened. And let's be honest does that vindicate vitamin D supplementation? I don't think so! If you want to make a change, get big and buffed or strong and sexy, get your lazy ass off the couch and out in the sun, work out regularly, prepare your own nutritious food and drop all useless supplements (see "Three Simple Rules of Smart Supplementation") ... but you know all that, already, right?
Some more general remarks: Now, I could hardly care less that this is yet another study showing that vitamin D3 is a supplemental non-starter., but there is one thing that really drives me up the walls and this is the fact that you as an intelligent and critical SuppVersity reader who is determined and willing to question what he reads on the Internet, but in 99% of the cases won't have access to full-texts of papers like this, are being mislead by abstracts, which are written for the sole purpose to tailor to the original research hypothesis
References
It sounds as if Carillo et al. had finally done, what no one else has done before them, ...
"Vitamin D supplementation in overweight and obese adults during resistance training induced an early improvement in peak power, and elevated vitamin D status was associated with reduced waist-to-hip ratio." (Carillo. 2012)So, according to the conclusion both strength and body composition improved n the course of the 12-week training intervention, which consisted of a 5min warm-up + light stretching (see also "Stretching Before Workouts Makes You Weak!"), followed by 8 machine-based (Kaiser Equipment) resistance exercises, namely
- leg extensions, leg flexions, leg presses,
- hip adductions & hip abductions,
- chest presses, seated rows & lat pull downs,
Serious training + serious nutrition = serious gains... but what about vitamin D?
Moreover, with the additional protein shake (360 kcal; 8 g fat, 54 g carbohydrate, 20 g milk protein isolate, 100IU vitamin D and 300mg of calcium) every participant had to consume during the hour following the exercise sessions, the scientists rightfully call their experimental protocol "anabolic". It is thus no wonder that aside from ostensible weight loss and strength gain, both of which you would expect in formerly sedentary subjects, the subjects in both groups did also increase their lean mass (see figure 2, right) .
Vitamin D3 a "Fat Synthesizer"!? Rodent Study Shows +33% Increased Fat Deposition in Vitamin D3 Supplemented Mice.")
"Something is rotten is rotten, here, and I can tell you Horatio heaven did not direct it"*
* I hope you like Shakespeare ;-)
- contrary to the actual vitamin D levels shown in figure 2 (small insert), the provision of 4,000IU/day of D3 did not (!) correlate with a reduction in waist-to-hip ratio,
- the vitamin D3 supplement did not increase serum calcium (see figure 3, top), and
- the participants who received the active supplement, exhibit an allegedly non significant, but still existent worsening of their glucose metabolism (cf figure 3, bottom)
"But it does make you stronger!" - Nope, that's another trick!
The latter is all the more true, because the participants in the vitamin D arm of the study may have increased their peak power faster (see figure 3), but the did not increase their overall strength on any of the exercises to a greater extend than the men and women in the placebo arm of the study.
Figure 4: Relative (left) and absolute strength gains (middle) as well as time course of peak power changes (calculations based on Carillo. 2012) |
From a mere statistical perspective, you could even argue that nothing happened. And let's be honest does that vindicate vitamin D supplementation? I don't think so! If you want to make a change, get big and buffed or strong and sexy, get your lazy ass off the couch and out in the sun, work out regularly, prepare your own nutritious food and drop all useless supplements (see "Three Simple Rules of Smart Supplementation") ... but you know all that, already, right?
Image 2: Does "doing science" come down to presenting only those facts that are in line with the orig. research hypothesis, these days? (img. geekology.com) |
"[...] that vitamin D supplementation during resistance training would result in greater gains in muscle mass and function as well as improved glucose tolerance compared to exercise training alone." (Carillo. 2012)and that irrespective of the fact that the actual data disproves this hypothesis!
References
- Carillo AE, Flynn MG, Pinkston, C, Markofki MM, Jian Y, Donkin SS, Teegarden D. Impact of vitamin D supplementation during a resistance training intervention on body composition, muscle function, and glucose tolerance in overweight and obese adults. Clinical nutrition (Edinburgh, Scotland) 3 September 2012.
- Chan AW, Hróbjartsson A, Haahr MT, Gøtzsche PC, Altman DG. Empirical evidence for selective reporting of outcomes in randomized trials: comparison of protocols to published articles. JAMA. 2004 May 26;291(20):2457-65
- Rantanen T, Masaki K, He Q, Ross GW, Willcox BJ, White L. Midlife muscle strength and human longevity up to age 100 years: a 44-year prospective study among a decedent cohort. Age (Dordr). 2012 Jun;34(3):563-70. Epub 2011 May 4.