NAD+ boosters are substances or interventions designed to increase levels of NAD+ (Nicotinamide Adenine Dinucleotide), a critical coenzyme found in every cell, essential for cellular energy production, metabolism, and repair processes. Boosting NAD+ levels is of significant interest in the fields of health and longevity, as declining levels of NAD+ are associated with aging and various age-related diseases.

NAD+ Precursors

NAD+ precursors are molecules that serve as substrates in the biosynthesis of NAD+. They can be converted into NAD+ within the body, thus serving as effective NAD+ boosters.

Nicotinamide Mononucleotide (NMN): A molecule that can directly stimulate NAD+ synthesis, playing a crucial role in energy metabolism and cell vitality.
Nicotinamide Riboside (NR): Another precursor that is converted into NMN in the body before participating in the synthesis of NAD+.
Nicotinamide (NAM): A form of vitamin B3, acts as an NAD+ precursor via the NAD+ salvage pathway.

Boosting NAD+ by Inhibiting NAD+ Consumers

NAD+ consumers are enzymes that use NAD+ as a substrate, reducing the available NAD+ in the cell. By inhibiting these consumers, more NAD+ remains available for other cellular processes.

Sirtuins: A family of proteins that deacetylate proteins and consume NAD+ in the process. Compounds like resveratrol can activate sirtuins and the subsequent cellular effects can create an environment where cells might maintain or produce NAD+ more efficiently, which could indirectly support NAD+ availability.
PARPs (Poly(ADP-ribose) polymerases): Enzymes involved in DNA repair that also consume NAD+. Inhibiting PARP activity can help maintain NAD+ levels.
CD38: A glycoprotein that uses NAD+; reducing CD38 levels or activity can potentially elevate NAD+ levels.

Other NAD+ Boosting Supplements

Beyond precursors and inhibitors of NAD+ consumers, several other supplements claim to boost NAD+ levels or improve NAD+ metabolism.

Resveratrol: While primarily known as a sirtuin activator, it might also have indirect effects on NAD+ levels and metabolism.
Quercetin: A flavonoid that can inhibit CD38 and may, therefore, increase NAD+ levels indirectly.
Pterostilbene: A polyphenol, similar to resveratrol, purported to have beneficial effects on NAD+ metabolism and sirtuin activation.

Interventions to Boost NAD+

Apart from supplements, certain lifestyle and dietary interventions may also support NAD+ levels.

Exercise: Regular physical activity has been shown to increase NAD+ levels, likely due to enhanced energy metabolism and increased demand for ATP.
Caloric Restriction: Reducing calorie intake without malnutrition can elevate NAD+ levels, potentially through the activation of sirtuins and improved metabolic efficiency.
Intermittent Fasting: This dietary approach can also elevate NAD+ levels, likely through mechanisms similar to caloric restriction, such as increased stress resistance and metabolic adaptations.

Comparison

Booster	Mechanism of Action	Relative Strength	Notes
Nicotinamide Mononucleotide (NMN)	NAD+ Precursor	High	Well-researched, direct precursor to NAD+
NR (Nicotinamide Riboside)	NAD+ Precursor	High	Converted to NMN in the body before participating in NAD+ synthesis
Nicotinamide (NAM)	NAD+ Precursor via the salvage pathway	Medium	More research needed on optimal dosing and long-term effects
Resveratrol	Sirtuin activator; may have indirect effects on NAD+ levels and metabolism	Low to Medium	Effectiveness may be influenced by individual metabolic differences and supplement formulation
Quercetin	Inhibits CD38; may increase NAD+ levels indirectly	Low to Medium	More research needed to quantify the impact on NAD+ levels
Pterostilbene	Similar to resveratrol; purported to have beneficial effects on NAD+ metabolism and sirtuin activation	Low to Medium	Requires more rigorous studies to confirm efficacy
Exercise	Increases NAD+ levels likely due to enhanced energy metabolism and increased demand for ATP	Medium to High	Effectiveness may depend on exercise type, intensity, and individual fitness level
Caloric Restriction	Elevates NAD+ levels potentially through the activation of sirtuins and improved metabolic efficiency	High	Sustained caloric restriction may have compliance challenges
Intermittent Fasting	Elevates NAD+ levels through mechanisms similar to caloric restriction	Medium to High	Impact may vary depending on the specific fasting protocol employed

Conclusion

NAD+ boosters, encompassing NAD+ precursors, inhibitors of NAD+ consuming enzymes, and various other supplements, along with non-supplemental measures like exercise and dietary modifications, offer promising avenues to enhance cellular vitality, metabolism, and potentially, longevity. While the science is evolving, understanding the diverse approaches to boost NAD+ highlights the multifaceted nature of cellular health and provides multiple pathways to explore for maintaining optimal health and combating age-related decline.