What is Betaine? (also known as Trimethylglycine)
Betaine, also known as trimethylglycine is an important naturally occurring amino acid in the body that has a variety of functions. It is most well-known for its function as an osmolyte1 (i.e. protecting cells against dehydration). However, it also acts as an antioxidant2, a regulator of homocysteine levels3 (marker of cardiovascular disease) and a protector of vascular function4. However, in recent times, betaine has received additional attention in regards to it role in creatine synthesis and regulation of nitric oxide levels5.
Where Does Betaine Come From?
Betaine is typically produced from sugar beet, but occurs widely in a range animal and plant food. Major dietary sources include seafood, wheat germ and spinach6.
There have been a number of studies conducted to determine the effects of betaine supplementation on measures of strength and power, with some conflicting results. One of the issues with these series of studies is the lack of consistency in study design. Studies have differed in their experimental design and measures as well as the dose of betaine.
Of the studies conducted in resistance-trained subjects, one found that 2.5g for 14 days lead to a moderate increase in total repetitions and volume load in the bench press exercise7. Another similar study found 2.5g for 14 days resulted in an increase in power and force in the vertical jump and squat respectively8. Yet another study found two-weeks of betaine supplementation at 2.5g per day in active, college males appeared to improve muscle endurance of the squat exercise, and increase the quality of repetitions performed9. Lastly, a study in active, college-aged men found 15 days of betaine supplementation (at 2.5g/day) did not increase peak concentric or eccentric force outputs during an isokinetic chest press but did appear to reduce subjective measures of fatigue to the exercise protocol10.
Studies have also examined the effect of betaine supplementation on nitric oxide levels. Two similar studies performed by the same group of researchers found that aggressive supplementation (i.e. 6g/day) for 1-week led to significant increases in nitric oxide levels11, 12. However, another more recent study using a range of doses did not find any significant increase in nitric oxide levels13. In explaining the contradictory findings, the authors postulated that betaine may be more effective at increasing nitric oxide levels in older and/or deconditioned individuals13 as these were the subjects that featured in the early studies that showed betaine supplementation increased nitric oxide levels11, 12.
Negative Side Effects of Betaine
There are over 10 studies where betaine has been given orally to a range of human subjects, however; no study has reported any significant negative side-effects.
Betaine Recommended Dosages & Timing
A number of studies have used a daily dose of 2.5g of betaine, while others have used up to 6g. However, most supplements that feature betaine as one of the key ingredients usually include it at a dose of `1.25g or 2.5g per dose.
There are very few supplements that include betaine on its own; rather it is commonly included as part of a mix with other amino acids in pre-workout supplements. Betaine also features in a number of pre-workout supplements.
As stated above, betaine most commonly features in pre-workout supplements. For this reason, it is often unnecessary to stack betaine with another supplement, as it normally comes pre-mixed with other key pre-workout ingredients.
As a natural and widely available constituent in animal and plant food, betaine is considered a safe dietary supplement.
1. Lever M & Slow S. The clinical significance of betaine, an osmolyte with a key role in methyl group metabolism. Clin Bioche. 2010; 43(9):732-744.
2. Kanbak G, et al. Betaine (trimethylglycine) as a nutritional agent prevents oxidative stress after chronic ethanol consumption in pancreatic tissue of rats. Int J Vitam Nutr Res. 2009; 79(2):79-86.
3. Olthof MR, Verhoef P: Effects of betaine intake on plasma homocysteine concentrations and consequences for health. Curr Drug Metab. 2005; 6(1):15-22.
4. Detopoulou P, et al. Dietary choline and betaine intakes in relation to concentrations of inflammatory markers in healthy adults: the ATTICA study. Am J Clin Nutr. 2008; 87(2):424-430.
5. Bloomer RJ, et al. Effect of betaine supplementation on plasma nitrate/nitrite in exercise-trained men. Journal of the International Society of Sports Nutrition. 2011; 8:5.
6. Craig SA. Betaine in human nutrition. Am J Clin Nutr. 2004;80(3):539-549.
7. 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. Journal of Strength and Conditioning Research. 2011; 25(12):3461–3471.
8. Lee EC, et al. Ergogenic effects of betaine supplementation on strength and power performance. Journal of the International Society of Sports Nutrition. 2010;7:27.
9. Hoffman JR, et al. Effect of betaine supplementation on power performance and fatigue. Journal of the International Society of Sports Nutrition. 2009;6:7.
10. Hoffman JR, et al. Effect of 15 days of betaine ingestion on concentric and eccentric force outputs during isokinetic exercise. Journal of Strength and Conditioning Research. 2011;25(8):2235–2241.
11. Iqbal O, et al. Betaine induced release of tissue factor pathway inhibitor and nitric oxide: implications in the management of cardiovascular disease. Presented at the 2006 meeting of Experimental Biology 2006.
12. Iqbal O, et al. Betaine a novel anticoagulant with combined nitric oxide and tissue factor pathway release potential. Implications in the management of peripheral vascular diseases. Journal of Thrombosis and Haemostasis. 2005; 3(Supplement 1):P0520.
13. Bloomer RJ, et al. Effect of betaine supplementation on plasma nitrate/nitrite in exercise-trained men. Journal of the International Society of Sports Nutrition. 2011;8:5.