TMG (Trimethylglycine) Powder, 50g by Life Extension is available now at Nature's Fix. Free from dairy and peanuts/tree nuts. Order today! Life Extension TMG Trimethylglycine (TMG) is also called glycine betaine, but the name trimethylglycine signifies that it has three methyl groups. Gluten Free, Non GMO, LE Certified. Promotes Healthy Homocysteine Levels. Dietary Supplement, Vegetarian. Our innovative formula helps support and maintain already-healthy homocysteine levels to support cardiovascular health. What Is TMG? Trimethylglycine (TMG) has been linked to heart health by supporting already-healthy homocysteine levels to promote healthy cardiovascular function. By having a positive impact on your homocysteine levels, TMG helps you stay healthy by supporting multiple systems throughout your body.