Last updated: September 26, 2026 · Originally published: September 12, 2026 · By Eternal Elixir Editorial
Quick answer: the TMG benefits with the best human evidence come from one job, donating a methyl group. In placebo-controlled trials, trimethylglycine (also sold as betaine anhydrous) lowered fasting homocysteine in healthy adults: by 12% at 1.5 g a day and 15% at 3 g a day after six weeks. Evidence for liver fat metabolism rests mostly on mechanism and animal work, the training data show a small strength effect, and body-composition results conflict. The main caution is cholesterol, which rose in pooled trials at 4 g a day or more.
For Australians comparing TMG benefits and products, our pick is Eternal Elixir TMG 2000mg. A three-capsule serve gives 2,000 mg, which sits inside the range that moved homocysteine and below the dose linked to higher cholesterol, and a 90-capsule bottle costs $44.99, or $1.50 a serve. Eternal Elixir makes this product, so weigh the pick with that in mind. Every study below is linked so you can check the numbers yourself.
Key points
- Homocysteine is the best-tested TMG benefit: 76 healthy adults saw fasting levels fall 12%, 15% and 20% below placebo at 1.5 g, 3 g and 6 g a day.
- A 2022 meta-analysis found doses under 4 g a day lowered homocysteine without the cholesterol rise seen at 4 g or more.
- Liver support is a sound mechanism with thin human outcome data. Pooled trials found no change in liver enzymes.
- Many Australians take TMG with NMN. The rationale is real, but no trial has tested the pair.
TMG Benefits in Australia: What Trimethylglycine Does
Trimethylglycine is glycine carrying three methyl groups. It was first isolated from sugar beet, which is where the name betaine comes from, and your body also makes it from choline. Beetroot, spinach, quinoa, wheat bran and shellfish all contain it. Typical diets supply roughly 0.5 to 2 g a day, according to the Dutch team behind the main dose trial (Olthof et al., 2003).
The supplement is the same molecule in a measured dose. Labels call it TMG, trimethylglycine or betaine anhydrous, and research papers call it betaine. Betaine HCl is a different product used for stomach acid, so check the label before you buy.
The table below sorts the claims you will see on Australian labels by the human evidence behind each one.
| Claimed benefit | Human evidence | What the trials found |
|---|---|---|
| Healthy homocysteine levels | Strong: several controlled trials and pooled analyses | Fasting homocysteine falls from 1.5 g a day, more at higher doses |
| Liver methylation and fat metabolism | Mechanism and animal work, limited human outcome data | No change in liver enzymes across pooled trials |
| Strength and training | Moderate: a 2024 pooled analysis of 17 studies | Small gain in maximal strength, mainly lower body |
| Body fat | Pooled analyses disagree | One pooled analysis found less fat mass, a larger one found no effect |
| Methyl support alongside NMN | Mechanism plus brief human data on nicotinamide | No trial has tested NMN with TMG |
How TMG Works: Methyl Groups and Homocysteine
Methylation is the transfer of a methyl group from one molecule to another. Cells use it to build neurotransmitters and creatine, to switch genes on and off and to process waste products. The main methyl carrier is S-adenosylmethionine (SAM), and each time SAM gives up its methyl group it leaves behind homocysteine.
Homocysteine has to be converted back into methionine to keep the cycle turning. The body has two routes. One depends on folate and vitamin B12. The other uses betaine and an enzyme called BHMT, which is most active in the liver. TMG feeds that second route directly, which is why it lowers homocysteine even in people whose folate intake is already adequate.
A 2021 review in Biology traced this pathway through the liver, muscle and other tissues, and tied most of betaine’s effects to keeping the cellular SAM to SAH ratio healthy (Arumugam et al., 2021). A review summarises other studies rather than testing anything itself, so it maps the mechanism without proving an outcome in people.
If you are new to the compound, our explainer on what trimethylglycine is and where it comes from covers the basics in more detail.
Benefit 1: Healthy Homocysteine Levels
This is the TMG benefit with the most human data. Homocysteine is measured with a routine blood test, and it works as a marker of how well the methylation cycle is keeping up.
In the key dose trial from Wageningen in the Netherlands, 76 healthy adults were split into four groups that took placebo or 1.5 g, 3 g or 6 g of betaine a day for six weeks. Fasting homocysteine finished 12%, 15% and 20% lower than placebo across the three doses. The researchers also ran a methionine loading test, which challenges the pathway with a protein-like load. On the first day of supplementation the rise after loading was already 23% smaller at 3 g and 35% smaller at 6 g than on placebo (Olthof et al., 2003).
A Finnish trial gave 42 adults with a high body weight 6 g of betaine or a placebo for 12 weeks while they followed a reduced-calorie diet. Plasma homocysteine fell in the betaine group. Weight and fat mass fell in both groups, with no difference between them, and total and LDL cholesterol were higher on betaine (Schwab et al., 2002).
A 2022 meta-analysis pooled the controlled trials on betaine and cardiovascular markers. Homocysteine fell by an average of 1.30 µmol/L. The authors’ subgroup analysis suggested doses under 4 g a day lowered homocysteine without the lipid rise reported at 4 g a day or more (Ashtary-Larky et al., 2022). That is the most useful single finding for choosing a dose.
What hasn’t been shown matters too. These trials measured a blood marker. None of them followed people long enough to show a change in health outcomes, so treat a lower homocysteine reading as the result, not a promise of anything beyond it.
Add TMG 2000mg to cart · $44.99
Benefit 2: Liver Methylation and Fat Metabolism
The liver holds most of the body’s BHMT, so it is where betaine does most of its work. Liver cells need methyl groups to make phosphatidylcholine, which they use to package fat and send it out into the blood. When methyl donors run short in animal models, that export slows and fat builds up inside liver cells. This is the thread behind TMG’s reputation for liver support, and it runs through the 2021 Biology review.
The human evidence is thinner than the mechanism. In the 2022 meta-analysis, betaine did not change the liver enzymes ALT, AST or GGT compared with placebo. Human trials that measured liver fat directly have mostly been run in people with a diagnosed liver condition, which puts them outside what a supplement guide should claim. A fair summary is that TMG contributes to normal methylation in the liver, and that human outcome data are still limited.
If liver support is your main reason for looking at TMG, compare it with the other options in our guide to liver support supplements sold in Australia and our TUDCA, NAC and milk thistle comparison.
Benefit 3: Strength, Training and Body Composition
Betaine also acts as an osmolyte, helping cells hold water under stress, and it supplies methyl groups for the body’s own creatine production. Both properties explain why it turns up in pre-workout formulas.
A 2024 meta-analysis pooled 17 studies with 317 participants taking betaine for at least a week. It found a small-to-moderate improvement in maximal strength (standardised mean difference 0.47), mainly in the lower body. Upper-body strength, cycling sprint power and muscular endurance showed no significant effect (Zawieja et al., 2024).
Body fat is where the evidence splits. In an eight-week trial of 23 young women new to resistance training, 2.5 g of betaine a day cut body fat by 3.3% against 1.7% on placebo, with no difference in strength gains (Cholewa et al., 2018). One author worked for DuPont, which supplies betaine. A 2019 meta-analysis of six trials with 195 participants found less fat mass on betaine (Gao et al., 2019). A larger 2022 meta-analysis found no significant effect on body weight, body fat or lean mass (Ashtary-Larky et al., 2022). Taken together, TMG is a modest training extra and should not be bought as a fat-loss tool.
Testosterone results are mixed as well. In 43 CrossFit athletes, three weeks of betaine at 2.5 g or 5 g a day raised testosterone by 7.0% and improved a workout score (Zawieja et al., 2023). In 29 teenage soccer players, testosterone rose across a 14-week season on 2 g a day of betaine and dipped late in the season on placebo (Nobari et al., 2021). In 36 premenopausal women, 3 g a day for eight weeks changed no sex hormone at all (Zawieja et al., 2026).
TMG With NMN: Why the Pairing Exists
This is the most common reason Australians add TMG to a stack. When cells use NAD+, they release nicotinamide, and the body clears surplus nicotinamide by methylating it. More NAD+ precursor in means more nicotinamide to clear and more methyl groups spent.
There is short-term human data on that cost. In a study of 30 adults, a single 300 mg dose of nicotinamide left plasma homocysteine 61% higher and plasma betaine 24.4% lower than in the water group three hours later (Sun et al., 2017). That was one dose of nicotinamide itself, not weeks of NMN.
No randomised trial has compared NMN alone with NMN plus TMG. The pairing is a reasonable way to cover the methyl cost, and it is not yet a tested protocol. Our guide to NMN benefits and the NAD+ pathway covers the precursor evidence, our comparison of NAD+ supplements in Australia sets out the options by cost, and the same methyl logic applies to nicotinamide riboside.
A simple routine is one Eternal Elixir NMN 500mg capsule in the morning with the TMG serve alongside it. The NMN is $59.99 for 90 capsules, or $0.67 a day. We looked at whether one 500 mg NMN capsule is enough in a separate guide, and at the best time of day to take NMN if you plan to pair the two.
TMG Doses in Trials vs TMG Products in Australia
Most TMG benefit claims skip the link between trial dose and bottle dose. The homocysteine trials used 1.5 to 6 g a day, and the strength studies mostly used 2 to 5 g. The table shows how much each product’s own label serve delivers. Prices are in AUD as of Sep 2026.
| Product | TMG per label serve | Form and pack | Price (as of Sep 2026) | Cost per label serve | Buy |
|---|---|---|---|---|---|
| Eternal Elixir TMG 2000mg (our pick) | 2,000 mg (3 capsules) | 90 capsules, 30 serves | $44.99 | $1.50 | View at Eternal Elixir |
| Bulk Nutrients TMG Capsules | 600 to 1,200 mg (1 to 2 capsules) | 120 capsules | $29.00 | $0.24 to $0.48 | Bulk Nutrients |
| Switch Nutrition TMG powder | 1,000 to 3,000 mg (1 to 3 scoops) | Powder, 150 scoops | $44.95 | $0.30 to $0.90 | Switch Nutrition |
| DoNotAge Pure TMG | 1,000 mg (2 capsules) | 60 capsules, 30 serves | $32.00 | $1.07 | DoNotAge |
| Simply Nootropics TMG B-Complex | 1,000 mg plus B vitamins (2 capsules) | 60 capsules, 30 serves | $49.00 | $1.63 | Simply Nootropics |
Eternal Elixir makes TMG 2000mg, and you can read more about who we are. It is our pick because it is the only capsule in this table whose label serve reaches the 1.5 g dose that lowered homocysteine, and it stays under 4 g a day. Bulk Nutrients has the lowest cost per capsule serve, and Switch Nutrition’s powder has the lowest cost per gram if you are happy to measure scoops.
Add TMG 2000mg to cart · $44.99
Who each product suits
- Eternal Elixir TMG 2000mg suits people who want a trial-range dose in capsules with no measuring. It costs more per gram than bulk powder, and three capsules a day is more to swallow than one.
- Bulk Nutrients TMG Capsules suit people who want a low daily dose at the lowest capsule price. The label’s top serve of 1,200 mg sits below the lowest trial dose.
- Switch Nutrition TMG powder suits people who don’t mind scooping a sweet powder and want the cheapest grams. Two or three scoops reach the trial range.
- DoNotAge Pure TMG suits people who already buy from that brand. Its recommended 1,000 mg a day is below the lowest trial dose.
- Simply Nootropics TMG B-Complex suits people who want TMG and activated B vitamins in one capsule. It carries 1,000 mg of TMG a day and has the highest cost per serve here.
For a wider line-up ranked on cost, see our best TMG supplements in Australia comparison.
How to Take TMG for the Best-Supported Benefits
- Dose: 1.5 to 3 g a day covers the homocysteine trials without reaching the 4 g level linked to higher cholesterol. Our 2,000 mg serve sits in that window.
- Timing: take it with a meal. Our product page suggests taking it with your morning NMN or splitting the three capsules across the day.
- How long: the homocysteine trials measured fasting levels at six and twelve weeks, so give it about two months before a repeat blood test.
- Measure it: if homocysteine is your reason for taking TMG, ask your GP for a test before you start and again after a couple of months. A marker you can measure is worth more than a feeling.
Our TMG dose and safety guide goes further on timing and splitting doses, and our guide to building a complete longevity stack shows where a methyl donor fits with the other pieces. For the category as a whole, see the best longevity supplements in Australia.
Why Eternal Elixir TMG 2000mg Is Our Pick
We set the serve to match the evidence. Three capsules give 2,000 mg of trimethylglycine as betaine anhydrous, above the 1.5 g that lowered homocysteine and well under the 4 g threshold for the cholesterol effect. The only other ingredients are rice flour and a vegetable capsule, so it suits vegans.
- 90 capsules, 30 serves: a month at the full 2,000 mg, or longer if you take fewer capsules.
- $44.99 a bottle: $1.50 per 2,000 mg serve.
- Multi-bottle savings: 2 bottles save 10%, 3 save 15% and 5 save 20%.
- Delivery: free shipping on orders over $100, and orders ship from Sydney within 24 hours.
Capsules also solve the taste problem. TMG powder is noticeably sweet, and capsules give the same dose every time without scoops. Browse the full Eternal Elixir range if you are building a wider routine.
Side Effects, Cholesterol and Who Should Avoid TMG
TMG is generally well tolerated. The side effects reported most often are digestive, including diarrhoea, bloating, cramps and nausea, and they are more common at higher doses (Healthline). Taking it with food and splitting the serve both help.
Cholesterol is the finding to take seriously. A 2021 meta-analysis of six randomised trials using at least 4 g a day for six to 24 weeks found total cholesterol rose by 0.34 mmol/L on average compared with placebo (Zawieja et al., 2021). The 2022 meta-analysis found the same pattern at 4 g a day or more, and no lipid change below that. More is not better with TMG.
Talk to your doctor or pharmacist before taking TMG if any of these apply:
- You are pregnant or breastfeeding. There is limited research on safety, and our product page says not to use it during pregnancy or breastfeeding.
- You have been told your cholesterol is high or you take a cholesterol-lowering medicine. Stay well under 4 g a day and ask your GP to recheck your lipids.
- You have a medical condition or take prescription medication. In rare cases TMG can push blood methionine up sharply, according to Healthline’s review.
- You already take other methyl donors such as a methylated B complex. Add one product at a time so you can tell what each is doing.
Children should not take TMG supplements unless a doctor advises it.
TMG Benefits: Frequently Asked Questions
What are the benefits of TMG?
The benefit with the strongest human evidence is lower fasting homocysteine, shown in placebo-controlled trials from 1.5 g a day. TMG also contributes to normal methylation in the liver, although human outcome data are limited. A 2024 meta-analysis found a small gain in leg strength, and the pooled studies on body fat disagree.
Add TMG 2000mg to cart · $44.99
Who should avoid taking TMG?
People who are pregnant or breastfeeding and children should not take it without medical advice. Anyone with high cholesterol, a medical condition or prescription medication should check with their doctor or pharmacist first, because doses of 4 g a day or more raised total cholesterol in pooled trials.
Can TMG raise blood pressure?
The trials don’t show that. The 2022 meta-analysis found betaine did not change blood pressure. In the 12-week Finnish trial at 6 g a day, diastolic blood pressure fell in both the betaine and placebo groups, with no difference between them. The marker to watch at high doses is cholesterol, not blood pressure.
Is TMG better than creatine?
No, they do different jobs. In a Brazilian trial, 20 g a day of creatine for 10 days raised muscle phosphocreatine, power and strength, while 2 g a day of betaine did none of these, and adding betaine to creatine added nothing (del Favero et al., 2012). Creatine has far more strength evidence. TMG is a methyl donor you might take for homocysteine, with a smaller training effect on top.
Does TMG raise testosterone?
Sometimes, in trained men and athletes. Testosterone rose 7.0% in 43 CrossFit athletes after three weeks, and stayed higher than placebo in teenage soccer players across a season. In 36 premenopausal women, 3 g a day for eight weeks changed no sex hormone. The effect is small, and the trials were short.
How long does TMG take to work?
Some effect on homocysteine shows from the first day: the rise after a methionine load was already smaller on day one of the Dutch trial. Fasting homocysteine was measured at six weeks, and the training studies here ran from three to 14 weeks. Plan on about two months before judging it with a blood test.
Is TMG the same as betaine anhydrous?
Yes. Trimethylglycine, TMG and betaine anhydrous are three names for the same compound, and the research uses the word betaine. Betaine HCl is a different product used for stomach acid, so check the label.
What is the best TMG supplement in Australia?
Our pick is Eternal Elixir TMG 2000mg, because its label serve of 2,000 mg reaches the trial range for homocysteine and stays under the 4 g level linked to higher cholesterol, in capsules with nothing to measure. Eternal Elixir makes it. Bulk Nutrients has the lowest capsule price and Switch Nutrition’s powder the lowest cost per gram. Our TMG supplements comparison covers more options.
Add TMG 2000mg to cart · $44.99
The Bottom Line
The TMG benefit you can count on is lower homocysteine, from 1.5 g a day upward, with the best balance below 4 g a day where cholesterol stays put. Liver support is a sound mechanism with limited human outcome data. Training effects are small. If you take NMN, adding TMG is a sensible way to cover the methyl cost, even though no trial has tested the pair.
Sources
- Olthof MR, van Vliet T, Boelsma E, Verhoef P. Low dose betaine supplementation leads to immediate and long term lowering of plasma homocysteine in healthy men and women. J Nutr. 2003;133(12):4135-8. PubMed 14652361
- 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. PubMed 12399266
- Ashtary-Larky D, Bagheri R, Ghanavati M, et al. Effects of betaine supplementation on cardiovascular markers: a systematic review and meta-analysis. Crit Rev Food Sci Nutr. 2022;62(23):6516-6533. PubMed 33764214
- Zawieja EE, Zawieja B, Chmurzynska A. Betaine supplementation moderately increases total cholesterol levels: a systematic review and meta-analysis. J Diet Suppl. 2021;18(1):105-117. PubMed 31809615
- Arumugam MK, Paal MC, Donohue TM, et al. Beneficial effects of betaine: a comprehensive review. Biology (Basel). 2021;10(6):456. PMC8224793
- Zawieja E, Machek S, Zanchi NE, et al. Effects of chronic betaine supplementation on exercise performance: systematic review and meta-analysis. J Sports Sci. 2024;42(22):2131-2144. PubMed 39514262
- Cholewa JM, Hudson A, Cicholski T, et al. The effects of chronic betaine supplementation on body composition and performance in collegiate females. J Int Soc Sports Nutr. 2018;15(1):37. PubMed 30064450
- Gao X, Zhang H, Guo XF, et al. Effect of betaine on reducing body fat: a systematic review and meta-analysis of randomized controlled trials. Nutrients. 2019;11(10):2480. PubMed 31623137
- Ashtary-Larky D, Bagheri R, Tinsley GM, et al. Betaine supplementation fails to improve body composition: a systematic review and meta-analysis. Br J Nutr. 2022;128(5):975-988. PubMed 34743773
- Zawieja E, Durkalec-Michalski K, Sadowski M, et al. Betaine supplementation improves CrossFit performance and increases testosterone levels, but has no influence on Wingate power. J Int Soc Sports Nutr. 2023;20(1):2231411. PubMed 37409757
- Nobari H, Kargarfard M, Minasian V, et al. The effects of 14-week betaine supplementation on endocrine markers, body composition and anthropometrics in professional youth soccer players. J Int Soc Sports Nutr. 2021;18(1):20. PubMed 33663545
- Zawieja E, Młodzik-Czyzewska M, Chmurzynska A. Betaine supplementation has no effect on sex hormones in premenopausal women with overweight or obesity: a randomized controlled trial. Clin Nutr ESPEN. 2026;75:103610. PubMed 42498161
- del Favero S, Roschel H, Artioli G, et al. Creatine but not betaine supplementation increases muscle phosphorylcreatine content and strength performance. Amino Acids. 2012;42(6):2299-305. PubMed 21744011
- Sun WP, Zhai MZ, Li D, et al. Comparison of the effects of nicotinic acid and nicotinamide degradation on plasma betaine and choline levels. Clin Nutr. 2017;36(4):1136-1142. PubMed 27567458
- Healthline. TMG supplements: benefits, side effects, dosage, and more. healthline.com
- Product pages and prices checked September 2026: Eternal Elixir TMG 2000mg, Bulk Nutrients, Switch Nutrition, DoNotAge, Simply Nootropics.
