Image 1: You really get a hefty dose of the history of physical culture with volume 1 + 2 of Randy Roach's Muscle, Smoke & Mirrors; I must forewarn you, though: These books have addictive potential, so don't buy them, when you have other important things (beside training ;-) on your schedule. |
My personal favorite in the first two volumes of Muscle Smoke & Mirrors is yet clearly the last third of the second volume about the history of dietary supplements. Aside from the notorious liver tabs and all sorts of "pro-diarrheal" protein supplements, stories about Joe Weider being willing to sell elephant shit, if only someone convinced him that it would further protein anabolism, and a lot of other informative and entertaining stuff, there was one supplement that has been largely forgotten by now that caught my interest - choline!
Choline is present in every human cell!
Although it does not carry the term "vitamin" in its name, choline is an essential water-soluble nutrient that is abundant in some of the typical old-school bodybuilding foods, such as calf liver, beef, eggs, chicken, turkey, sardines, cod, milk and a lot of those green vegetables, many people today believe they must have been invented by the vegans and vegetarians.
Are vitamin supplements bad for me? I have addressed the question in some detail in two previous blogposts in response to the ever resurfacing horror stories about vitamin E, selenium and prostate cancer (Part I), and the media hype around the results of the Iowa Women's Health Study (Part II). So before you bombard me with further questions, go and check out these and a couple of posts on hormesis, here at the SuppVersity ;-)
At first sight it may thus seem that the supplemental choline some of the pros took with each and every meal was at best a waste of time and money, if not a potential health hazard; after all, we are seeing all those horror news about potential negative side-effects from the overconsumption of all sorts of allegedly harmless vitamins pop up in the media in ever shorter time intervals, as of late.Choline - essential, but already (over-)abundant?
To answer this question we will initially have to identify what choline does in our bodies. As the name that has been derived from the greek word for bile ("chole") implies, choline has been initially identified as a major component of the juices and cells of the pancreas and liver. Scientists realized only later that it is an absolutely essential constituent of each and every cell of our body, where choline with its fat-modifying properties increases the flexibility of the cell membranes and handles the in- and outflux of fat-based nutrients and waste products, respectively.
If we take into consideration that choline is also one of the rare trimethylated molecules in our diets and acts as an important methyl donor that is required for both, the proper activation and deactivation of genes, and as precursor to the neurotransmitter acetylcholine, it is hardly surprising that the list of mostly neurological and cardiological pathologies stemming from marginal or full-blown choline deficiency is endless:
Image 2: The purportedly dangerous cholesterol bombs, aka eggs, are among the #1 sources of dietary choline |
- high homocysteine levels, cardiovascular disease,
- high blood pressure, high triglyceride levels
- fatigue, insomnia,
- memory and nerve problems,
- liver dysfunction, kidney failure
(probably subsequent to a lack of phosphatidylcholine), - impaired growth and failure to thrive,
- abnormalities in bone and red blood cell formation,
- infertility
Figure 1: The daily choline intake of most Americans is below the respective RDA, of which some scientists already speculate that it may already be too low. (USDA. 2011) |
- 0-6 months: 125 mg
- 6-12 months: 150 mg
- 1-3 years: 200 mg
- 4-8 years: 250 mg
- males 9-13 years: 375 mg
- males 14 years and older: 550 mg
- females 9-13 years: 375 mg
- females 14-18 years: 400 mg
- females 19 years and older: 425 mg
- Pregnant females of any age: 450 mg
- Lactating females of any age: 550 mg
- 15 eggs
- 10-11 eggs and 1lbs of chicken
- 1 cup of almonds, three cups of rice, 5 eggs, 1lbs of chicken and five ounces of liver
Bigger, stronger, faster, leaner, ... what the pros said
For most, yet by probably not all competitive bodybuilders back in the day, improvements in heart and overall health were yet probably not the major incentive to ramp up their choline intake to levels, where the fishy smell your sweat, urine and other bodily fluids will develop when you ingest way too much choline eventually drowned out the foul protein farts, they got from the hardly digestible protein powders of the late 1970s. What they were looking for was the competitive edge:
- Performing more reps and training at an even higher volume - With dietary / supplemental choline being a necessary precursor to acetylcholine, which in turn facilitates skeletal muscle contraction, it was only reasonable to assume that the 2-3x per day 2-3h marathon workouts some of the guys were performing, would increase the risk to deplete your choline levels so that the acetylcholine production would come to a standstill and your muscles would simply refuse to contract.
- Greater protection and faster repair of muscle damage - Due to its established anti-oxidant effects and its status as an essential and functional constituent of the cell wall, it appears logical that adequate levels of choline would be necessary to both protect and repair skeletal muscle.
- Increased leanness and vascularity - In view of the fact that it has been known since the early 1950s that choline's role in the oxidation of fatty acid goes well beyond serving as a source for the phospholipids that would carry them out of the liver and to the mitochondria of skeletal muscle and other metabolically active tissue (Artom. 1953). Even the assumption that choline supplementation will propel the oxidation of fatty acids, promote lower body fat levels and lead either directly (fat loss) or indirectly (reduced inflammation = reduced subcutaneous water) to a more vascular look, was far from being a bro-scientific 'dumb-and-barbell story'.
... what exercise and nutrition science says
Despite the last-named restraints and the unlikeliness that we will find a study on choline supplementation on 200lbs+ bodybuilders on a 8,000kcal/day+ diet, I guess, you will not mind, if we take a brief look at whether or not those "logical" benefits (#1-3, above) have actually been observed in peer-reviewed studies.
- Potential effects of supplemental choline on training load / volume Van Allwörden et al. weer among the first scientists who tried to establish a connection between the long-established exercise induced decreases choline, exercise performance and fatigue (Van Allwörden. 1993). Just like Buchman et al. who report similar results in marathon runners (Buchman. 2000), Allwörden et al. had yet to acknowledge that the 0.2g/kg lecithin (a choline source) induced compensation of the 17% decrease in serum choline levels compared to the control group did not lead to increase the performance of the adolescent triathletes in their study. And though these results stand in contrast to a 1992 study by Sandage et al. which found a minimal increase in 10k running times in response to the ingestion of 2.8g of choline 1h prior to the run, most authors of pertinent reviews do acknowledge the theoretical merit of the hypothesis, but speculate that the decline in choline is rarely ever pronounced enough to for choline supplements to illicit immediate ergogenic benefits (e.g. Jäger. 2007; Penry. 2008). Long-term studies on potential downstream effects of decreased oxidative stress, improved cellular regeneration and utilization of fat soluble nutrients, on the other hand, are missing so that the preliminary answer to the question whether choline supplementation would allow you to train longer, or at an overall higher volume must be: Very unlikely!
- Potential effects of supplemental choline on muscle damage, repair and growth While Michel et al. observed in isolated muscle cells that choline deficiency induced a cascade of changes in both the oxidative metabolism (downregulated), as well as the fatty acid composition of the cell membranes (Michel. 2011), which was characterized by a shift towards mono- and away from saturated fatty acids, it is somewhat far-fetched to use this as "evidence" for a potential beneficial effect of choline supplementation; after all, we are dealing with isolated, choline depleted muscle cells in a petri dish and cannot even say for sure whether a potentially hightened susceptibility of the monounsaturated fats in the cell wall will lead to an increase in skeletal muscle damage in response to strenuous exercise. Against the background that there is no other convincing scientific evidence that would suggest that supplemental choline - in the absence of dietary choline deficiency (or pathologies related to the latter, such as liver cirrhosis) - would make your muscle bullet proof, this is the 2nd purported benefit the real-world significance of which turns out to be more than questionable.
- Potential effects of supplemental choline on fat loss and vascularity Interestingly enough, the "fat loss" hypothesis, appears to be the one with the most convincing scientific evidence to support it. In 2002, for example, Hongu and Sachan observed a shift towards increased fatty acid oxidation in 19 healthy women who participated in a combined carnitine + choline + exercise trial. Moreover, these substrate repartitioning effects were "sustained until wk 2 after cessation of choline plus carnitine supplementation and exercise" (Hongu. 2002). In a previous rodent trial a similar stack that included caffeine, carnitine and choline had lead to body fat reductions "similar to those due to mild exercise" (Hongu. 2000), an observation that would support a previous hypothesis of the authors stating that the combination of carnitine and choline favors an "incomplete oxidation of fatty acids and disposal of their carbons in urine as acylcarnitines in humans" and could thusly help to increase the absolute and relative amount fat loss on a diet. In view of the well-established lipolytic effects of caffeine a "CCC stack", i.e. caffeine + carnitine + choline, could thus in fact make a valuable addition to a sound exercise and diet regimen. Whether it would really make a visible difference, remains yet questionable.
References:
- von Allwörden HN, Horn S, Kahl J, Feldheim W. The influence of lecithin on plasma choline concentrations in triathletes and adolescent runners during exercise. Eur J Appl Physiol Occup Physiol. 1993;67(1):87-91.
- Artom, Camillo. Role of Choline in the Oxidation of Fatty Acids by the Liver. J. Biol. Chem. 1953 205: 101-111.
- Buchman AL, Awal M, Jenden D, Roch M, Kang SH. The effect of lecithin supplementation on plasma choline concentrations during a marathon. J Am Coll Nutr. 2000 Nov-Dec;19(6):768-70.
- Detopoulou P, Panagiotakos DB, Antonopoulou S, Pitsavos C, Stefanadis C. Dietary choline and betaine intakes in relation to concentrations of inflammatory markers in healthy adults: the ATTICA study. Am J Clin Nutr. 2008 Feb;87(2):424-30.
- Hongu N, Sachan DS. Caffeine, carnitine and choline supplementation of rats decreases body fat and serum leptin concentration as does exercise. J Nutr. 2000 Feb;130(2):152-7.
- Hongu N, Sachan DS. Carnitine and choline supplementation with exercise alter carnitine profiles, biochemical markers of fat metabolism and serum leptin concentration in healthy women. J Nutr. 2003 Jan;133(1):84-9.
- Jäger R, Purpura M, Kingsley M. Phospholipids and sports performance. J Int Soc Sports Nutr. 2007 Jul 25;4:5.
- Penry JT, Manore MM. International Journal of Sport Nutrition and Exercise Metabolism 2008, 18(2):191-203
- Rajaie S, Esmaillzadeh A. Dietary choline and betaine intakes and risk of cardiovascular diseases: review of epidemiological evidence. ARYA Atheroscler. 2011 Summer;7(2):78-86.
- Roach, Randy. Muscle Smoke & Mirrors. Volume 1-2. AuthorHouse. 2008-2011.
- Sachan DS, Hongu N. Increases in VO2max and metabolic markers of fat oxidation by caffeine, carnitine, and choline supplementation in rats. J Nutr Biochem. 2000 Oct;11(10):521-6.
- Sandage BW, Sabounjian RN, White R, Wurtman RJ: Choline citrate may enhance athletic performance. Physiologist 1992, 35(4):236.
- USDA. FSRG Dietary Data Brief -- No. 9 –Dietary Intakes of Choline. 2011
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