Nicotinamide mononucleotide (NMN) as an anti-aging health product - Promises and safety concerns

Abstract

Background: Elderly population has been progressively rising in the world, thus the demand for anti-aging heath products to assure longevity as well as to ameliorate age-related complications is also on the rise. Among various anti-aging health products, nicotinamide mononucleotide (NMN) has been gaining attentions of the consumers and the scientific community.

Aim of review: This article intends to provide an overview on the current knowledge on promises and safety concerns of NMN as an anti-aging health product.

Key scientific concepts of review: Nicotinamide adenine dinucleotide (NAD⁺) levels in the body deplete with aging and it is associated with downregulation of energy production in mitochondria, oxidative stress, DNA damage, cognitive impairment and inflammatory conditions. However, NMN, as the precursor of NAD⁺, can slow down this process by elevating NAD⁺ levels in the body. A number of in vivo studies have indicated affirmative results of therapeutic effects for various age-induced complications with NMN supplementation. One preclinical and one clinical study have been conducted to investigate the safety concerns of NMN administration while a few more human clinical trials are being conducted. As there is a large influx of NMN based anti-aging products on the market, proper clinical investigations are urgently needed to find out the effectiveness and safety of NMN supplementation.

Keywords: Age-induced diseases; Anti-aging; Nicotinamide adenine dinucleotide; Nicotinamide mononucleotide; Supplement.

Graphical abstract

Fig. 1

Percentage of global population aged 65 years or over according to the medium-variant projection (UN, 2019).

Fig. 2

Chemical structure of nicotinamide mononucleotide (NMN).

Fig. 3

NAD+ biosynthesis pathways in which NMN involves. Biosynthetic pathways of NAD+ in mammalian cells in which NMN involves are Preiss–Handler and salvage pathways, and the salvage pathway is the major source of NAD+. NAMPT-nicotinamide phosphoribosyltransferase; ATP-adenosine triphosphate; ADP-adenosine diphosphate; NMNAT-nicotinamide mononucleotide adenylyltransferase; NRK-nicotinamide riboside kinases; NAPRT-nicotinate phosphoribosyltransferase; NADS-nicotinamide adenine dinucleotide synthetases.

Fig. 4

Causes for reducing NAD+ levels when aging and mechanism underlying anti-aging activity of NMN. DNA damage, chronic inflammation, oxidative stress and increasing NAD+ consuming enzymes (sirtuins, CD38/CD157, PARP, TNKS and BST) accelerate NAD degradation. The reduced levels of NAD+ cause downregulation of energy production in mitochondria, leading to aging and various age-associated diseases. NMN supplementation can reinstate NAD+ levels in the body through biosynthesis pathways, reversing the aging process and preventing age-associated diseases.