Ingredient
Moderate evidenceBetaine Anhydrous
Also known as: betaine, trimethylglycine, TMG
An under-rated power and output ingredient with a small but real evidence base.
What it is
Betaine anhydrous, also called trimethylglycine or TMG, is a compound derived from beetroot. It plays a role in cellular hydration and in methylation processes in the body. In sports supplements it is included for a modest boost to strength and power output.
How it works
The leading theories are that betaine acts as an osmolyte (helping cells hold water and resist stress) and supports creatine synthesis. Several studies show small improvements in power and training volume. The effect is real but modest, and it depends on a proper dose rather than the trace amounts some labels carry.
Effective dose
The studied dose is around 2.5g per day, taken consistently. As with beta-alanine, the benefit appears to build with regular use rather than from a single serving. Check that a pre-workout actually lists 2.5g rather than burying a token amount in a blend.
Safety and upper limit
Betaine is well tolerated at the typical 2.5g dose. Higher doses can cause stomach upset or a fishy body odour in some people. It has a long history of food and supplement use.
Where you find it
Pre-workouts and strength/power formulas.
Top Pre-Workout picks
The highest-scoring products in the category where Betaine Anhydrous matters most.
Frequently asked
How much betaine anhydrous should I take?
Around 2.5g per day, taken consistently. Many pre-workouts under-dose it below this level.
What does betaine do for lifting?
It offers a small but real boost to power output and training volume, likely via cellular hydration and supporting creatine synthesis.
Is betaine the same as TMG?
Yes. Betaine anhydrous and trimethylglycine (TMG) are the same compound.
Related guides
This page is educational and not medical advice. Doses are general guidance from the published research, not a personal prescription. Before starting any supplement that could affect a medical condition or interact with medication, speak to a qualified clinician.