Science

The science behind Element 5

NMN and NAD⁺: what the research says

NAD⁺ is a molecule every cell uses to turn food into energy, and levels of it fall as we age. NMN is one of the building blocks the body uses to make NAD⁺. This page explains what NMN is, what published human studies have found so far, where the evidence is still limited, and how Element 5 NMN is made and tested.

Key facts

  • NMN (β-nicotinamide mononucleotide) is a direct precursor of NAD⁺.
  • NAD⁺ levels decline with age in human tissue.[1]
  • Human trials of NMN have used 250–1,200 mg a day for 6–12 weeks, and several found that blood NAD⁺ levels rose.[4][7]
  • Element 5 NMN contains 500 mg of β-NMN per capsule, HPLC tested to ≥99% purity, made in a GMP-certified UK facility.
  • Every batch is independently lab tested, and all reports are published on our batch lab test directory.

What is NAD⁺?

NAD⁺ (nicotinamide adenine dinucleotide) is a coenzyme found in every living cell. It is essential to energy metabolism, helping convert the food you eat into the energy your cells run on. It is also used by enzymes involved in cellular maintenance, including the sirtuins, a family of proteins widely studied in the biology of ageing.[2]

Why do NAD⁺ levels fall with age?

Studies of human tissue have found that NAD⁺ levels are lower in older adults than in younger ones.[1] Researchers think this reflects both increased use of NAD⁺ by repair processes and changes in how efficiently the body makes it. Because NAD⁺ is so central to how cells work, how to support healthy NAD⁺ levels is an active area of research.[2]

What is NMN and how does it get into cells?

NMN (nicotinamide mononucleotide) sits one step before NAD⁺ in the pathway the body uses to make it. It occurs naturally in small amounts in foods such as edamame, broccoli, cabbage, avocado and cucumber, but at levels far too low to match a supplement dose.

NAD⁺ itself is a relatively large molecule that does not pass easily into cells, which is why research has focused on smaller precursors like NMN. In 2019, a study in mice identified a transporter protein, Slc12a8, that can carry NMN directly into cells.[3] How NMN is taken up in different human tissues is still being studied.

What have human studies of NMN found?

Most NMN research has been done in animals, but a growing number of human clinical trials have now been published. The table below summarises six of them. Each studied NMN as an ingredient, not Element 5's product specifically.

Area studied Who took part Daily dose Length What was found Study design
NAD⁺ levels 80 healthy middle-aged adults 300, 600 or 900 mg 60 days Blood NAD⁺ rose at every dose versus placebo, with the largest rises at 600–900 mg. [4] Randomised, double-blind, placebo-controlled
Aerobic capacity 48 amateur runners 300, 600 or 1,200 mg 6 weeks Ventilatory threshold and aerobic capacity improved in the 600 mg and 1,200 mg groups; the 300 mg group did not differ significantly. [5] Randomised, double-blind
Muscle function 42 healthy men aged 65+ (20 completed the full 12 weeks) 250 mg 12 weeks Blood NAD⁺ levels rose, with some improvements in measures of muscle function such as gait speed and grip. [7] Randomised, double-blind, placebo-controlled
Sleep & fatigue 108 older adults 250 mg 12 weeks Reported drowsiness and fatigue improved, particularly when NMN was taken in the afternoon. [8] Randomised, double-blind, placebo-controlled
Insulin sensitivity 25 postmenopausal women with prediabetes 250 mg 10 weeks Muscle insulin sensitivity improved versus placebo. [6] Randomised, double-blind, placebo-controlled
Hair quality 15 women aged 40–50 500 mg 12 weeks Average hair diameter increased by about 4.6%. [9] Single group, no placebo

Scroll the table sideways on mobile. Sources are listed in full at the bottom of the page.

What the research doesn't tell us yet

We think it matters to be clear about the limits of the evidence:

  • The studies are small and short. Most involved fewer than 110 people over 6 to 12 weeks. Longer and larger trials are needed.
  • Doses vary. Trials used between 250 mg and 1,200 mg a day. Some effects, such as the aerobic capacity changes in runners, were only seen at 600 mg or more.[5]
  • Not every study had a placebo group. The hair study, for example, had a single group of 15 women and no comparison group.
  • Results differ between people. Age, health, diet and activity all influence NAD⁺ levels and how someone responds.

NMN is a food supplement, not a medicine. It is not intended to diagnose, treat, cure or prevent any disease.

How Element 5 NMN is made and tested

Each Element 5 NMN capsule contains 500 mg of β-nicotinamide mononucleotide in a vegan HPMC capsule, with no fillers or binders. It is manufactured in the UK in a GMP-certified facility.

Every batch is independently lab tested before it is sold. Published reports for each batch include a certificate of composition, an HPLC purity assay confirming ≥99% purity, a heavy metals screen (lead, arsenic, mercury and cadmium), and yeast and mould testing. You can look up your own batch, using the code on the base of your bottle, in our batch lab test directory.

Is NMN legal in the UK?

In the UK, NMN has not been deemed a novel food requiring authorisation. The EU has a separate regulatory system, so its decisions do not automatically apply to the UK. For more detail, read NMN in the UK: current regulatory status.

Further reading

References

  1. Massudi, H., Grant, R., Braidy, N., Guest, J., Farnsworth, B., & Guillemin, G. J. (2012). Age-associated changes in oxidative stress and NAD+ metabolism in human tissue. PLoS ONE, 7(7), e42357. doi.org/10.1371/journal.pone.0042357
  2. Imai, S., & Guarente, L. (2014). NAD+ and sirtuins in aging and disease. Trends in Cell Biology, 24(8), 464–471. doi.org/10.1016/j.tcb.2014.04.002
  3. Grozio, A., Mills, K. F., Yoshino, J., et al. (2019). Slc12a8 is a nicotinamide mononucleotide transporter. Nature Metabolism, 1(1), 47–57. doi.org/10.1038/s42255-018-0009-4
  4. Yi, L., Maier, A. B., Tao, R., et al. (2023). The efficacy and safety of β-nicotinamide mononucleotide (NMN) supplementation in healthy middle-aged adults: a randomized, multicenter, double-blind, placebo-controlled, parallel-group, dose-dependent clinical trial. GeroScience, 45(1), 29–43. doi.org/10.1007/s11357-022-00705-1
  5. Liao, B., Zhao, Y., Wang, D., Zhang, X., Hao, X., & Hu, M. (2021). Nicotinamide mononucleotide supplementation enhances aerobic capacity in amateur runners: a randomized, double-blind study. Journal of the International Society of Sports Nutrition, 18(1), 54. doi.org/10.1186/s12970-021-00442-4
  6. Yoshino, M., Yoshino, J., Kayser, B. D., et al. (2021). Nicotinamide mononucleotide increases muscle insulin sensitivity in prediabetic women. Science, 372(6547), 1224–1229. doi.org/10.1126/science.abe9985
  7. Igarashi, M., Nakagawa-Nagahama, Y., Miura, M., et al. (2022). Chronic nicotinamide mononucleotide supplementation elevates blood nicotinamide adenine dinucleotide levels and alters muscle function in healthy older men. npj Aging, 8, 5. doi.org/10.1038/s41514-022-00084-z
  8. Kim, M., Seol, J., Sato, T., Fukamizu, Y., Sakurai, T., & Okura, T. (2022). Effect of 12-week intake of nicotinamide mononucleotide on sleep quality, fatigue, and physical performance in older Japanese adults: a randomized, double-blind placebo-controlled study. Nutrients, 14(4), 755. doi.org/10.3390/nu14040755
  9. Study of NMN and hair quality in women aged 40–50 (2025). Cosmetics, 12(5), 204. www.mdpi.com/2079-9284/12/5/204

This page summarises published research on NMN as an ingredient. The studies above did not test Element 5 products, and their results may not apply to everyone. Food supplements should not be used as a substitute for a varied, balanced diet and a healthy lifestyle. If you are pregnant, breastfeeding, taking medication or have a medical condition, speak to a healthcare professional before taking any supplement.