8 Best Reasons to Love NAD+, An Anti-Aging Powerhouse
Our cells use NAD+ to make sirtuin proteins work, to regulate biological pathways, and protect cells from age-related decline. Sirtuins play a crucial role in maintaining the length of telomeres, which are DNA strand end caps that keep our chromosomes from unraveling. Scientists have linked long telomeres with longevity.
As we age, our NAD+ levels drop. One reason is that a compound called CD-38 destroys NAD+. This is a good thing if done modestly, because CD-38 keeps our NAD+ from getting too high and impinging on important biochemical processes, such as sleep-wake and hunger cycles. But as we get older, CD-38 gets too ambitious and destroys too much NAD+. The balance is upended, resulting in too much CD-38 and not enough NAD+.
Let's take a closer look at NAD+ and its powerhouse anti-aging benefits.
#1 NAD+ and Telomere Length
Inside the nucleus of a cell, our genes are arranged along twisted, double-stranded molecules of DNA called chromosomes. At the ends of the chromosomes are stretches of DNA called telomeres, which protect our genetic data, make it possible for cells to divide, and hold some secrets to how we age.
Each time a cell divides, the telomeres get shorter. When they get too short, the cell can no longer divide; it becomes inactive (senescent) or it dies (apoptosis). This telomere shortening process is associated with aging and a higher risk of death.
NAD+ is required for functioning of the sirtuin proteins that help maintain the length of telomeres.
Foods and supplements rich in polyphenols, such as resveratrol and pterostilbene, may activate sirtuins and contribute to extending lifespan, but emerging evidence suggests sirtuins function best when NAD+ is activated.
#2 NAD+ and DNA Repair
DNA is highly vulnerable to damage, which can include broken DNA strands and gene mutations. As DNA damage accumulates, it contributes to the aging process and can result in specific lifespan-shortening diseases and weakened immunity.
Our DNA can fight back. When damaged, DNA activates an enzyme known as PARP-1 that carries out DNA repair within cells. To do this, however, PARP-1 relies on NAD+. To carry out its function, PARP-1 consumes enormous amounts of NAD+. As we get older and our NAD+ becomes gradually depleted, the ability of PARP-1 to repair DNA is significantly compromised.
Replenishing NAD+ supports a healthy DNA repair process.
#3 NAD+ and Immune Cell Signaling
As we age, our immune cells become inconsistent––some become overactive (which can contribute to autoimmune disease) and others slow down (which increases the risk of infection). This process, called immunosenescence, is intimately related to mitochondrial function and energy balance, both of which depend on NAD+ activity.
Thus, adequate intracellular NAD+ is vital for youthful cellular energy, a critically important factor in fending off immunosenescence and maintaining a healthy immune system.
#4 NAD+ and the Energy Enzymes that Fuel Us
A universal feature of aging is the loss of cellular energy, which results in diminished ATP levels and inadequate cellular fuel necessary to power your body. ATP (adenosine triphosphate) is the main source of energy for most cellular processes. All living things, plants and animals, require a continual supply of energy in order to function. Above all, the energy is used for all the processes required to keep us alive.
One cause of this energy loss is a breakdown in the efficiency of the electron transport chain, the main pathway through which we extract energy from food. NAD+ is an essential component in this process.
Studies show that restoring electron transport chain function by raising levels of NAD+ is a rapid and efficient means of promoting the essential enzymes involved in energy extraction and sustaining youthful cell function. Maintaining good NAD+ levels supports ongoing physiological health and wellness.
#5 NAD+ and Chromosome Stability
Our chromosomes are complex structures housing our DNA. Think of it this way: DNA is in genes; genes are on chromosomes.
Access to DNA strands for “reading out” genetic instructions requires biochemical control of those proteins to make sure each gene functions properly, but like any complex molecular structure, chromosomes can become unstable. Eventually, instability triggers errors in how genes are interpreted, which ultimately contribute to harmful changes in cell function and structure. Aging is accelerated in the presence of increased chromosome instability.
The enzymes involved in sustaining stable chromosomal structures require NAD+ in order to function properly. When sufficiently present, NAD+ contributes to longevity in animal models. Whereas, when enzymes that require NAD+ to function are inactive, chromosome structure suffers and cells replicate abnormally.
#6 NAD+ and Brain Health
NAD+ appears essential for sustaining brain health due to its effect on neurotransmitters. In fact, a study in the Journal of Biomedical Science suggests it meets the criteria for a neurotransmitter itself.
Neurotransmitters are brain chemicals that relay signals between nerve cells and thereby help regulate body-wide functions such as mood, appetite, and stress.
#7 NAD+ and Cellular Energy Production
NAD+ was first discovered as an important part of the process that channels chemical energy from foods to the ATP fuel our cells require. NAD+ is itself a form of “energy currency” similar to ATP, the complex organic chemical that provides energy to drive many processes in living cells.
NAD+ is also a functional signaling molecule in processes related to energy production, including PARP-1 and sirtuins. When DNA damage occurs, PARP-1 consumes large quantities of NAD+, leading to reduced energy production. In addition, high levels of NAD+ can activate sirtuins, permitting them to carry out their metabolic and stress-protective responses, thus contributing to longevity.
Supporting efficient energy production and adequate ATP levels requires consistent and abundant NAD+. This is critical because as our cellular energy diminishes, so does our life force.
#8 NAD+ and Sirtuins, the Regulators of Cellular Aging
Sirtuins are major regulators of cellular aging because they influence fundamental functions such as DNA repair and inflammatory responses. They also influence whether cells enter a replicative cycle, or instead, die a programmed death.
Compounds that activate sirtuins are eagerly sought as chemical “fountains of youth.” Familiar supplements like resveratrol, pterbolene and quercetin have been evaluated as promising sirtuin activators.
Sirtuin activation has shown great promise in supporting a healthy cardiovascular system and healthy brain function, but these longevity-promoters cannot function without sufficient NAD+.
The bottom line: A sufficient supply of NAD+ is needed for sirtuins to function properly, supporting normal DNA repair and a healthy inflammatory response.
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