TMG Supplement Explained: The Methyl Donor Paired With NMN

TMG (trimethylglycine, or betaine) donates methyl groups that the liver uses to turn homocysteine back into methionine. In healthy adults, 1.5 to 6 g a day for 6 weeks lowered fasting homocysteine by 12 to 20 percent compared with placebo. Smaller studies have looked at training performance, with mixed results. It also helps cells hold water and keep their volume steady.

When the body clears extra nicotinamide, part of NAD+ turnover, it attaches a methyl group to it. Some people pair NAD+ precursors such as NMN with a methyl donor like TMG to support that demand. This is a reasonable idea based on biochemistry, but the pairing has not been tested in a human trial.

Each 2-capsule serving of Enhanced NMN contains 200 mg of TMG, alongside NMN 750 mg, resveratrol 200 mg, pterostilbene 100 mg and vitamin B12 750 mcg. That is well below the 1.5 to 6 g a day used in homocysteine studies and within the range people get from food.

At high doses of 4 g a day or more, TMG raised total cholesterol slightly in trials, so people watching their cholesterol should check with a clinician before taking large amounts. Anyone who is pregnant or nursing, has a kidney or liver condition, or takes regular medication should also ask first.

No. TMG and creatine are different molecules. TMG supplies methyl groups to the methionine cycle, which the body also uses to make creatine, so the two are related biochemically, but TMG does not replace creatine.

Not quite. TMG is betaine in its plain form. Betaine hydrochloride (betaine HCl) is a salt form sold as a digestive acid supplement, which is a different use.

Rich dietary sources include wheat germ and wheat bran, spinach, beets and seafood, especially shellfish. Typical diets supply roughly 0.5 to 2 g a day.

TMG does two main jobs. It donates methyl groups that the liver and kidneys use to turn homocysteine back into methionine, which then becomes SAMe, the main methyl donor for many reactions. It also acts as an osmolyte, helping cells keep their water balance and volume steady.

There is no official recommended amount. Homocysteine studies used 1.5 to 6 g a day, and typical diets supply about 0.5 to 2 g. Enhanced NMN provides 200 mg per 2-capsule serving as a supporting amount alongside NMN. Follow your product label, and ask a clinician before taking gram doses.

TMG has no known timing effect of its own, so take it at a time you will remember each day. The Enhanced NMN label says two capsules in the morning, with or without food. If a separate gram-dose TMG product upsets your stomach, taking it with a meal may help.

TMG is a normal part of the diet and is generally well tolerated. At gram doses some people notice mild digestive upset. In trials, 4 g a day or more for six weeks or longer raised total cholesterol by about 0.34 mmol/L, far above the 200 mg in Enhanced NMN.

Yes. Betaine anhydrous is TMG (trimethylglycine) in a dry powder form with no water bound to it. Betaine HCl is a different salt form sold as a digestive acid supplement.

Many people pair NMN with a methyl donor such as TMG, because the body attaches a methyl group to extra nicotinamide as it uses and recycles NAD+. The idea is sound biochemistry but has not been tested in a human trial. Enhanced NMN already includes 200 mg of TMG with 750 mg of NMN, so there is no need to add a separate product for that supporting amount.

No. TMG is glycine with three methyl groups attached, which is what lets it donate methyl groups. Glycine on its own has none to give.