One of the most important molecules found inside every single living cell is NAD, (nicotinamide adenine dinucleotide). NAD has earned its reputation for the multiple essential roles it plays in maintaining healthy cellular functioning and life itself. As our understanding of why we age continues to grow, we’ve discovered that the aging process is also greatly influenced by NAD.1
Not only is NAD required to sustain life, but to sustain an energetic and healthy life. It is required for our bodies to carry out the business of living. This includes basic vital functions such as breathing, eating, drinking, walking and thinking. It is as critical to sustain life as food and water.2
NAD plays a critical role in cellular energy production and the regulation of many different aspects of cellular metabolism. As a coenzyme, NAD is a “helper” molecule necessary for enzymes to complete their activities, influencing natural processes throughout the body. NAD is also important for healthy mitochondrial function, skeletal muscle development, metabolic health, and plays a key role in cellular repair.3
Unfortunately, we experience a steady decline in NAD as we age because our bodies are typically unable to maintain the balance of NAD production and use. In fact, by the time we are middle-aged, our NAD levels can drop to half of what we had in our youth. This causes it to become increasingly difficult for our bodies to adequately supply us with enough NAD each day.1,2,4
The decline in NAD as we age can lead to a decreased capacity to naturally produce cellular fuel or ATP for energy.1 This progressive decline in healthy cellular functioning can ultimately lead to accelerated cellular aging, loss of energy, limited recovery after injury, fatigue, frailty, and other signs of Age-Associated Cellular Decline (AACD).3
NAD collectively refers to the two forms of NAD — NAD+ and its reduced form NADH. NAD exists in two forms because it works as an electron carrier involved in “redox” (reduction-oxidation) reactions. These redox reactions continuously occur inside our cells where NAD is necessary to transfer elections.1
One of the most important cellular processes involving redox reactions is the creation of the cellular fuel within our mitochondria through cellular respiration. For our mitochondria to produce the huge amounts of ATP our cells need for energy during the course of each day, they require a constant stream of electrons released from glucose and fatty acids in the foods we eat.
During the fascinating and complex three-step process of cellular respiration, NAD is crucial for collecting the electrons released at the end of each stage. Then, NAD transfers the electrons within the cell to their final destination inside the mitochondria.3 This flow of electrons is what allows the complex process of ATP production to occur.1 And, it’s ATP that naturally energizes our cells to do their daily work.
A decline in NAD is thought to be highly associated with some of the most common signs related to aging, like feeling tired faster and more frequent fatigue.5 Although our bodies can make NAD+ from precursor foods found in our diets, our body’s ability to produce enough becomes more of a challenge as we age.1,2
We’re still uncovering exactly why NAD+ declines as we age. However, we have pinpointed two likely contributors to the progressive decline of NAD+:3,6 One is simply the inability of cells to produce enough NAD+. Another is related to an enzyme on the surface of immune cells called CD38. CD38 plays an important role in the inflammatory response of our immune system. But, to carry out its functions, CD38 consumes large amounts of NAD+. It’s possible that age-related low-grade inflammation causes CD38 to increase, resulting in a decrease in NAD+.2,7
The decline of NAD+ is often gradual and frequently goes unnoticed at first. Over time, however, a lack of NAD+ can affect cellular repair mechanisms, resiliency, protection and healthy mitochondrial functioning.5 Once this loss becomes progressive, we may begin to notice more frequent fatigue, a loss of physical energy, a slowed metabolism and a reduction in mental sharpness.8
This progressive loss of cellular function as a result of declining NAD+ can continue to trickle down into other areas of our health. These include more serious conditions commonly associated with aging such as frailty, chronic inflammation, compromised immunity, heart disease and neurodegenerative diseases.6,9,10Given the critical role of NAD+ in healthy cellular functioning, energy production, muscle development and mitochondrial homeostasis, it’s clear this molecule is vital to maintaining good health and longevity. Current research on aging now shows that increasing the amount of NAD+ within our cells could be a very beneficial way to help increase healthy cellular functioning and address the key drivers of AACD.3.9