In the US, human trials give the best guide to NMN and TMG doses. Multi-week NMN studies used 250 to 1,250 mg per day. Betaine (TMG) studies used 1.5 to 6 g per day. A 500 mg NMN + 250 mg TMG label dose sits in the middle of the NMN range but far below tested TMG amounts.
The NMN Dose Ladder in Human Trials
Researchers have tested NMN at several daily amounts. No single trial compared every dose. The ladder below comes from separate studies with different people, lengths and goals.
The lowest multi-week dose is 250 mg. In a 10-week trial, postmenopausal women with prediabetes who were overweight or obese took 250 mg NMN daily. Their muscle insulin sensitivity and muscle insulin signaling increased after NMN, but not after placebo (Yoshino 2021). In healthy older men, 250 mg per day for 6 or 12 weeks was well tolerated and raised blood NAD+ and related metabolites. The gait speed and grip gains were only nominally significant, and the authors said they "should be validated in larger studies" (Igarashi 2022).
The largest dose-comparison trial randomized 80 healthy middle-aged adults to placebo, 300, 600 or 900 mg NMN daily for 60 days. Blood NAD rose in every NMN group and was highest at 600 and 900 mg. Six-minute walking distance improved compared with placebo. Insulin resistance (HOMA-IR) did not change compared with placebo. Industry co-sponsored the study (Yi 2023).
At the top of the ladder, 1,250 mg daily for up to 4 weeks caused no changes beyond normal physiological variation and no severe adverse events. The NMN supplier funded that trial and employed its authors (Fukamizu 2022).
| Study | NMN dose per day | Length | Main finding |
|---|---|---|---|
| Irie 2020 | 100, 250 or 500 mg (single dose) | 5 hours | No significant symptoms or changes in heart rate, blood pressure or oxygen saturation |
| Yoshino 2021 | 250 mg | 10 weeks | Muscle insulin sensitivity and signaling rose vs placebo |
| Igarashi 2022 | 250 mg | 6 or 12 weeks | Blood NAD+ rose; gait and grip gains only nominal |
| Yamaguchi 2024 | Two 125 mg capsules | 8 weeks | NAD+ in blood mononuclear cells rose; open-label, 11 men |
| Yi 2023 | 300, 600 or 900 mg | 60 days | Blood NAD rose, highest at 600-900 mg; HOMA-IR unchanged |
| Liao 2021 | 300, 600 or 1,200 mg | 6 weeks | Threshold measures rose at 600 and 1,200 mg; VO2max unchanged |
| Fukamizu 2022 | 1,250 mg | Up to 4 weeks | No severe adverse events; supplier-funded |
The runner trial included 48 trained runners. Oxygen uptake and power at ventilatory thresholds rose more at 600 and 1,200 mg than in the control group. VO2max and peak power did not change (Liao 2021). For more detail on NMN alone, read the Wellness Nest guide on how much NMN per day trials used.
Where a 500 mg NMN Label Dose Sits
Each 2-capsule serving of AgeAura Pure NMN + TMG NAD+ Complex lists 500 mg NMN. That amount falls between the 300 mg and 600 mg groups of the multi-week trials.
Researchers tested 500 mg only as a single dose. In 10 healthy men, single doses of 100, 250 and 500 mg caused no significant symptoms over 5 hours (Irie 2020). None of the multi-week trials above used exactly 500 mg daily.
Keep the limits in mind. These trials were small. Most lasted only weeks. Industry funded some of them. A higher NAD level in blood is a lab marker. It does not promise how you will feel.
Each serving also contains 100 mg trans-resveratrol, 150 mg quercetin, 50 mg apigenin, 1 mg spermidine and 400 mcg DFE folate as L-5-MTHF. The spermidine comes from wheat germ extract, so the label lists wheat as an allergen. The label also says the product is free from gluten, soy, dairy, fish and shellfish.
TMG Doses: Studies vs Diet vs a 250 mg Label
TMG is betaine. Its main roles are osmolyte and methyl donor. As a methyl donor, it works in the methionine cycle, mainly in the liver and kidneys (Craig 2004). Betaine gives methyl groups to homocysteine to form methionine (Zeisel 2003).
Why pair TMG with NMN? The enzyme NNMT uses SAM as a methyl donor to convert nicotinamide into methylnicotinamide. This step makes SAH, a precursor of homocysteine (Li 2024). The theory is that NMN breakdown uses methyl groups and TMG can replace some of them. This is a mechanistic rationale only. No published human trial has tested NMN + TMG against NMN alone. Our article on NMN and TMG together explains the reasoning in more detail.
Now the doses. Most people get roughly 0.5-2 g of betaine per day from food. In healthy adults, 1.5, 3 and 6 g per day for 6 weeks lowered fasting homocysteine by 12%, 15% and 20% compared with placebo (Olthof 2003). A meta-analysis of 5 trials that used at least 4 g per day found that homocysteine fell by 1.23 µmol/L (McRae 2013).
High doses also showed a trade-off. One meta-analysis found that total cholesterol rose by 0.34 mmol/L at 4 g/day or more (Zawieja 2021). A larger analysis found total cholesterol rose by 14.12 mg/dL and LDL by 10.26 mg/dL, while homocysteine fell by 1.30 µmol/L (Ashtary-Larky 2022).
The label's 250 mg TMG is far below the tested amounts. It is also below normal dietary intake. Treat it as a small methyl-donor amount, not a homocysteine dose. No trial tested 250 mg. Do not expect it to lower homocysteine. Do not assume the cholesterol finding applies at 250 mg either.
Food Sources of Betaine
Most of your betaine comes from food. These foods have the most betaine per 100 g: wheat bran 1,339 mg, wheat germ 1,241 mg, spinach 645 mg, pretzels 237 mg, shrimp 218 mg and wheat bread 201 mg (Zeisel 2003).
By those figures, 100 g of spinach contains more betaine than one 2-capsule serving. Your normal diet matters more for total betaine than the 250 mg on the label.
How US Adults Can Take the Label Dose
The label says to take 2 capsules daily. That one serving gives the full 500 mg NMN and 250 mg TMG. The capsules are vegan and non-GMO. A USA cGMP-certified partner facility makes them.
Timing is your choice. In the Yamaguchi 2024 trial, participants took NMN once daily before breakfast (Yamaguchi 2024). That is what one trial did. It is not a rule. Our guide on when to take NMN compares morning and night.
A pill organizer helps you take the dose at the same time each day. To see what else readers pick, browse Wellness Nest best sellers.
Dietary supplements are not FDA-approved to treat, cure or prevent disease. Talk to your doctor before use if you are pregnant, nursing, under 18, taking medication or managing a medical condition. The product is not a medicine and does not replace medical care.
Consistency Over Escalation
Take the same dose every day. Do not increase it. The trials tested fixed daily doses over weeks. They did not test people who added more capsules over time. Do not double up after a missed day. Do not stack this product with another NMN or betaine supplement.
AgeAura Pure NMN + TMG NAD+ Complex costs $69.95 one-time. Subscribe-and-save options are 15% off for 1 bottle every 4 weeks, or 14% off for 3 every 12 weeks or 6 every 24 weeks. A 90-day money-back guarantee applies. You can also browse the Wellness Nest best sellers before you decide.
Frequently Asked Questions
Is 500 mg of NMN a day too much?
Multi-week trials used 250 to 1,250 mg daily. The trials that reported safety described NMN as well tolerated, and the 1,250 mg trial reported no severe adverse events (Fukamizu 2022). Researchers tested 500 mg only as a single dose, so 500 mg daily over weeks has not been studied directly.
Does 250 mg of TMG lower homocysteine?
No trial has tested 250 mg. Studies that lowered homocysteine used 1.5 to 6 g per day (Olthof 2003). The label amount is a small methyl-donor amount, not a homocysteine dose.
Has the NMN + TMG combination been tested in people?
No. No published human trial has tested NMN + TMG against NMN alone. The pairing rests on a mechanistic rationale about methyl groups, not on a proven clinical benefit.
Can I take extra capsules for a stronger effect?
Follow the label: 2 capsules daily. The trials used steady daily doses, not increasing ones. Talk to your doctor before you change your intake.
Is NMN legal in US supplements?
Yes. On September 29, 2025, FDA confirmed that NMN is lawful in dietary supplements (NPA). FDA found that NMN was sold as a supplement in the US as early as 2017.
About the Author
Dr. Marcus Hale — Dr. Marcus Hale is the resident health researcher behind Wellness Nest's editorial team, translating peer-reviewed sports-nutrition and longevity research into practical daily guidance for US readers.
