Tru Niagen is a dietary supplement made by ChromaDex that contains nicotinamide riboside (NR), a specialized form of vitamin B3. Its purpose is to raise levels of a molecule called NAD+ in your cells, which plays a central role in energy production, DNA repair, and cellular maintenance. The standard dose is 300 mg per day, and at that amount, clinical trials have shown whole blood NAD+ increases of roughly 40 to 50 percent within two weeks.
How It Works in Your Body
NAD+ is a molecule every cell in your body needs to function. It helps your mitochondria convert food into usable energy, and it activates enzymes responsible for repairing damaged DNA. The problem is that NAD+ levels decline with age. By some estimates, levels drop significantly by middle age, which researchers believe contributes to the fatigue, slower recovery, and cellular wear associated with getting older.
Your body can’t absorb NAD+ directly from a pill. Instead, Tru Niagen supplies nicotinamide riboside, a precursor that your cells can take in and convert. Once NR enters a cell, specialized enzymes add a phosphate group to it, turning it into an intermediate called NMN. From there, another set of enzymes completes the conversion to NAD+. This two-step process happens in the main body of the cell, while the final NAD+ gets distributed to mitochondria and other compartments where it’s needed.
What the Clinical Evidence Shows
Multiple human trials have measured what happens when people take NR at various doses. In one well-cited study, daily doses of 100, 300, and 1,000 mg raised whole blood NAD+ by 10, 48, and 139 percent respectively, with changes appearing within two weeks. Another trial found that 300 mg of NR per day increased NAD+ in immune cells by about 60 percent.
These are consistent, reproducible increases, and they’re among the more robust findings in the NAD+ supplement space. That said, higher NAD+ in blood cells doesn’t automatically translate into specific health outcomes you can feel. The clinical data is strong on the “raises NAD+” question but still limited on longer-term endpoints like disease prevention, cognitive performance, or measurable anti-aging effects in humans. Most of the dramatic health benefits (protection against obesity, improved endurance, metabolic improvements) come from animal studies, not human trials.
Safety and Side Effects
NR has a clean safety profile across the studies conducted so far. Doses up to 1,000 mg per day taken for five months have shown no evidence of toxicity or serious adverse effects. A trial testing an unusually high dose of 3,000 mg per day (well above the recommended amount) in people with Parkinson’s disease found no moderate or severe adverse events. The most commonly reported mild side effects at that high dose were nausea, headache, fatigue, muscle cramps, and digestive discomfort, all of which resolved on their own.
One thing researchers watch for is homocysteine, an amino acid that can rise when you take large amounts of certain B vitamins and is associated with cardiovascular risk. Some NR studies have noted a slight initial rise in homocysteine, but the overall methylation system (which keeps homocysteine in check) remained intact. Unlike niacin, the most common form of vitamin B3, NR does not cause flushing, the uncomfortable skin reddening and warmth that leads many people to stop taking niacin.
ChromaDex’s NR formulation received a “no questions” letter from the FDA through the GRAS (Generally Recognized as Safe) process in 2016, meaning the agency did not challenge the company’s safety assessment for use in foods and beverages. This is not the same as FDA approval, which supplements don’t require, but it does indicate a formal safety review took place.
Dosage
The standard Tru Niagen capsule contains 300 mg of nicotinamide riboside, taken once daily. This is the dose used in many clinical trials and produces a meaningful NAD+ increase without approaching any safety thresholds. Clinical data supports safety at doses up to 1,000 mg per day, and the established upper limit for a related form of B3 (nicotinamide) is 900 mg per day. Some users take two capsules for a 600 mg daily dose, though the incremental benefit of doubling the dose is not well characterized in terms of real-world health outcomes.
How NR Compares to NMN
The main alternative NAD+ precursor on the market is NMN (nicotinamide mononucleotide). Both raise NAD+, but they take slightly different routes to get there, and the comparison is more nuanced than marketing from either side suggests.
NR enters cells directly and gets converted to NMN inside the cell before becoming NAD+. NMN, interestingly, appears to be converted back into NR outside the cell before it can enter, at least according to several studies. An enzyme on cell surfaces strips the extra phosphate from NMN, turning it into NR for absorption. This has led some researchers to argue that NR is the more direct precursor, since NMN may need to become NR first anyway. However, other research has identified a possible dedicated NMN transporter in certain tissues, though that finding remains debated.
One pharmacokinetic study found that NR had superior absorption characteristics compared to both niacin and nicotinamide. Human trials of NMN also show NAD+ increases, sometimes dramatic ones, though the measurement methods and study designs vary enough to make direct head-to-head comparisons difficult. No large, well-controlled trial has directly compared NR and NMN in the same group of people using the same measurement techniques.
What Makes Tru Niagen Proprietary
Tru Niagen isn’t just a brand name slapped on a generic ingredient. ChromaDex holds or exclusively licenses a portfolio of patents covering NR’s composition, crystalline forms, manufacturing methods, and uses as an NAD+ precursor. These patents originate from research at Cornell University, Dartmouth College, and Queen’s University Belfast, among others. ChromaDex also has an exclusive manufacturing agreement with W.R. Grace & Co. for the production of NR itself, making it the sole commercial supplier of this specific form of the compound. This patent protection is why you won’t find other supplements using the Niagen-branded NR, and it’s a key reason the product tends to cost more than generic NMN supplements.