I'm now here to discuss the second in our two-part article on the potential spinach may offer in regards to performance. In the first part, I discussed how spinach was a superfood, a little powerhouse full of vitamins and minerals. I also talked about was how little iron spinach contained despite popular belief, and whether an active compound in spinach (ecdysterone) brought about an anabolic response and the potential for increased muscle mass. I'm sad to say unless you're a rat, a pig or a sheep you're unlikely to benefit from any significant anabolic response, sorry! If this is the case, then why did Popeye love his spinach leaf so much?
Well, what most people are unaware of is that spinach also contains a molecule called betaine. Yes, the same betaine that you would otherwise find in sugar beets, wheat bran, beetroot and spinach [1][2]. It can also be synthesised from choline in your body when dietary intake exceeds your current metabolic requirement (Ueland 2011). Interestingly enough though, if we look at figure 1 you'll see spinach ranks higher in its betaine content than beets do, almost 3x higher in fact! (Craig. 2004) You can see wheat bran and wheat gem are at the top, which makes me wonder if Popeye had a wheat allergy. Why else would he miss these out of his diet?

(Figure 1)

So, the question is...
What is betaine and does it have any affect on performance or muscle growth?
Betaine is otherwise known as Trimethylglycine (TMG) but for the purpose of this article I'm just going to be referring to it as betaine. Most of you will associate betaine with beetroots and its vasodilatory properties. After all, every health store across the country has been advertising how beetroot’s nitrates can increase vasodilation – it’s been this years’ must-have supplement! I'm afraid to say the marketing claims behind beetroot and its ability to increase vasodilation of the blood vessels levels are mostly false.Despite its reputation, betaine has no affect on serum nitrate or nitrite levels. At least this is what two independent studies have found [3][4]. One study did find that consuming 6g of betaine per day did in fact increase levels of nitric oxide [5], but that's 3x the dose of the previous studies, and would equate to the consumption of almost 1kg of spinach, or 3kgs worth of beetroot! This hardly seems worth the effort when other supplements will have the same affect. Instead, you could take 6g of the amino acid L’citrulline.

Another claims surrounding betaine is that it can help decrease fat mass, increase power output and increase muscle protein syntheses (Apicella 2012). According to a more recent study, betaine supplementation of only 1.25g twice per day saw increases in lean muscle tissue by as much as 4lbs, arm size by 10% and decreased fat mass by 7% in trained males [7]. Unfortunately, these claims and studies are locker room myths, misrepresented data or otherwise studies that failed to bring about noticeable results [8,9,10,11].
Although betaine doesn’t affect vasodilation or fat loss, it has been shown to increase growth hormone and IGF-1 by 7.8% following a morning fasted training session, and reduce cortisol levels raised by morning fasted training by 6.1% [12]. Both of these can only be a plus, but there are studies contradicting these results.

Where betaine really shines through is in its ability to reduce homocysteine levels in the body. Homocysteine is a marker of cardiovascular disease, and it is thought that higher circulating levels of homocysteine are indicative of a higher risk of strokes and heart attacks. Higher levels have also been linked to the risk of developing Alzheimer’s disease [13]. Betaine has shown promise across numerous human trails, being the number one supplement for reducing homocysteine. A single dose has previously lead to around a 10% reduction in persons with normal homocysteine levels [14] and a 20-40% reduction in those with high levels of homocysteine [15]. 

(Spinach - Popeye's pre-workout)

So this begs the question…
Was Popeye right? Does spinach increase strength and muscle mass?
Given the evidence I’ll have to say no, until the research is clearer. Research around betaine’s ability to increase muscle growth, sports performance and positively affect growth hormone is conflicting, but there’s one thing for certain: it’s a wonder drug at reducing homocysteine levels and keeping yourself at bay from any type cardiovascular diseases! I think Popeye must have realized the importance of keeping his homocysteine levels in check, as well as an intolerance to wheat that left spinach as the go-to food for his daily betaine fix!

 Sources:
[1] Craig SA. Betaine in human nutrition. Am J Clin Nutr. (2004)
[2] Zeisel SH, et al. Concentrations of choline-containing compounds and betaine in common foods. J Nutr. (2003)
[3] Bloomer RJ et al. Effect of betaine supplementation on plasma nitrate/nitrite in exercise-trained men. J ISSN (2011)
[4] Trepanowski JF, et al. The effects of chronic betaine supplementation on exercise performance, skeletal muscle oxygen saturation and associated biochemical parameters in resistance trained men. J Strength Cond Res. (2011)
[5] BETAINE INDUCED RELEASE OF TISSUE FACTOR PATHWAY INHIBITOR AND NITRIC OXIDE: IMPLICATIONS IN THE MANAGEMENT OF CARDIOVASCULAR DISEASE
[6]Ochiai M, Hayashi T, Morita M, et al. Short-term effects of L-citrulline supplementation on arterial stiffness in middle-aged men. Int J Cardiol. 2012;155(2):257-61. doi: 10.1016/j.ijcard.2010.10.004.
[7] Cholewa, J. M., et al. Effects of betaine on body composition, performance, and homocysteine thiolactone. J Int Soc Sports Nutr. 2013 Aug 22; 10(1): 39.
[8] Schwab U, et al. Betaine supplementation decreases plasma homocysteine concentrations but does not affect body weight, body composition, or resting energy expenditure in human subjects. Am J Clin Nutr. (2002)
[9] Apicella JM, et al. Betaine supplementation enhances anabolic endocrine and Akt signaling in response to acute bouts of exercise. Eur J Appl Physiol. (2013)
[10] Hoffman JR, et al. Effect of 15 days of betaine ingestion on concentric and eccentric force outputs during isokinetic exercise. J Strength Cond Res. (2011)
[11] Pryor JL, Craig SA, Swensen T. Effect of betaine supplementation on cycling sprint performance. J Int Soc Sports Nutr. (2012)
[12] Apicella JM, et al. Betaine supplementation enhances anabolic endocrine and Akt signaling in response to acute bouts of exercise. Eur J Appl Physiol. (2013)
[13] McCaddon A, et al. Total serum homocysteine in senile dementia of Alzheimer type. Int J Geriatr Psychiatry. (1998)
[14] Schwab U, Törrönen A, Toppinen L, et al. Betaine supplementation decreases plasma homocysteine concentrations but does not affect body weight, body composition, or resting energy expenditure in human subjects. Am J Clin Nutr. 2002;76(5):961-7.
[15] Effect of Folic Acid and Betaine Supplementation on Flow-Mediated Dilation: A Randomized, Controlled Study in Healthy Volunteers

About Chris Hall
As the founder of Hall Training Systems, it is my mission to provide you with the very best personal training experience. I set up Hall Training Systems as Oxford's leading personal training service in nutrition, performance and weight loss, ensuring I can deliver the very best in training techniques.
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