Nikotinamid-Ribosid
Also known as: NR, niagen, nicotinamide riboside chloride, vitamin B3, Nicotinamide Riboside
Overview
Nicotinamide Riboside (NR) is a naturally occurring form of vitamin B3 found in trace amounts in milk and other foods. It functions as a crucial precursor to nicotinamide adenine dinucleotide (NAD+), a coenzyme vital for cellular metabolism. Supplementation with NR aims to elevate NAD+ levels, thereby supporting cellular energy production, mitochondrial function, and potentially mitigating age-related declines such as sarcopenia and cognitive impairment. NR is orally bioavailable, leading to dose-dependent increases in blood NAD+ levels, and is generally recognized as safe (GRAS) for human consumption. While research on NR is ongoing, several randomized controlled trials (RCTs) and systematic reviews exist, indicating its effectiveness in raising NAD+ levels, though clinical efficacy on functional outcomes remains somewhat inconclusive.
Benefits
The primary benefit of Nicotinamide Riboside (NR) is its ability to dose-dependently increase whole blood NAD+ levels. Studies show increases ranging from 22% to 142% with daily doses of 100 mg to 1000 mg over 2 weeks, with these elevated levels sustained over longer periods (8-12 weeks). This effect is robust and statistically significant across multiple high-quality RCTs. While some studies suggest potential improvements in physical performance parameters in older adults, the evidence for significant improvements in muscle strength and function is inconsistent and often shows no benefit compared to placebo. For instance, in patients with mild cognitive impairment, NR did not improve or possibly declined Short Physical Performance Battery (SPPB) scores. Secondary effects, such as anti-inflammatory properties and metabolic improvements, have been suggested but require further confirmation. The most targeted populations are older adults and individuals with mild cognitive impairment or sarcopenia, but functional improvements in these groups are mixed. While NAD+ increases are clinically significant, the translation to functional outcomes remains limited, indicating that more research is needed to establish clear functional benefits.
How it works
Nicotinamide Riboside (NR) functions as a precursor to nicotinamide adenine dinucleotide (NAD+). Once ingested, NR is converted intracellularly into NAD+, a coenzyme essential for numerous biological processes. NAD+ plays a critical role in redox reactions, mitochondrial function, DNA repair mechanisms, and the activation of sirtuins (SIRT1-7), which are proteins involved in cellular health and aging. By increasing NAD+ levels, NR enhances cellular energy metabolism, potentially improves mitochondrial biogenesis and function, and modulates inflammatory pathways. NR is orally bioavailable, allowing for its efficient absorption and subsequent conversion to NAD+ within the body's cells, leading to dose-dependent increases in blood NAD+ metabolites.
Side effects
Nicotinamide Riboside (NR) is generally well tolerated, with no serious adverse events reported in randomized controlled trials (RCTs) at doses up to 1000 mg/day. Unlike niacin, NR does not cause flushing. Common side effects (occurring in more than 5% of users) have not been reported. Uncommon side effects (1-5%) occasionally include minor gastrointestinal symptoms, though these are not statistically different from placebo groups. Rare side effects (less than 1%) have not been observed in high-quality RCTs. Currently, no significant drug interactions have been reported, but caution is advised when co-administering with medications that affect NAD+ metabolism. There are no formally established contraindications, but its safety during pregnancy, lactation, or in individuals with severe illnesses has not been thoroughly studied. Studies have primarily focused on otherwise healthy overweight adults and older adults, and safety appears consistent across these groups.
Dosage
Evidence suggests that Nicotinamide Riboside (NR) can increase NAD+ levels starting at a minimum effective dose of 100 mg/day, with larger doses yielding greater effects. Optimal dosage ranges commonly used in clinical trials are between 300 mg/day and 1000 mg/day. A dose of 1000 mg/day has been shown to be safe and effective in significantly raising NAD+ levels. The maximum safe dose demonstrated in trials is up to 1000 mg/day for durations of 8-12 weeks; long-term safety beyond this dose or duration is not yet well established. NR is typically taken once daily, which is sufficient to maintain elevated NAD+ levels. The common supplement form, NR chloride, has confirmed oral bioavailability, and no special cofactors are required for its absorption.
FAQs
Is NR safe?
Yes, Nicotinamide Riboside (NR) is generally well tolerated and considered safe at doses up to 1000 mg/day, with no serious adverse effects reported in clinical trials.
How quickly does it work?
NR begins to increase NAD+ levels in the blood within approximately two weeks of consistent supplementation. However, any potential functional benefits may require longer-term use or may be limited.
Does NR improve muscle strength?
Evidence regarding NR's effect on muscle strength is mixed. While it increases NAD+ levels, many studies, especially in older adults, have shown no significant improvement in muscle strength or physical function.
Is NR better than other NAD+ precursors?
NR generally has better bioavailability and fewer side effects (like flushing) compared to niacin. Its comparison with NMN (Nicotinamide Mononucleotide) is ongoing, but both are known to effectively increase NAD+ levels.
Research Sources
- https://www.nature.com/articles/s41598-019-46120-z – This randomized, double-blind, placebo-controlled trial involving 140 overweight adults demonstrated that Nicotinamide Riboside (NR) supplementation dose-dependently increased blood NAD+ levels (22%-142%) over 8 weeks without significant adverse effects. The study highlights NR's efficacy in boosting NAD+ but did not assess functional outcomes.
- https://www.science.org/doi/10.1126/sciadv.adi4862 – This randomized, placebo-controlled trial with 30 heart failure patients showed that NR increased NAD+ levels. However, it found no significant improvement in muscle function or metabolic markers, suggesting that while NR boosts NAD+, its functional benefits in this specific population may be limited or require longer intervention.
- https://pubmed.ncbi.nlm.nih.gov/40275690/ – This systematic review and meta-analysis of randomized controlled trials concluded that while Nicotinamide Riboside (NR) effectively increases NAD+ levels, its effects on sarcopenia measures, including muscle strength and gait speed, were inconsistent or showed no significant improvement. The review highlights heterogeneity in study populations and outcomes, indicating a need for more targeted research on functional benefits.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC12022230/ – This article discusses the effects of NR, noting that in patients with mild cognitive impairment, NR (1 g/day) did not show a benefit or possibly indicated a decline in some measures, such as the Short Physical Performance Battery (SPPB) score, compared to placebo. This suggests that functional improvements are not universally observed despite NAD+ increases.
