What are the benefits of NAD+ for the skin?

Sirtuins are enzymes activated by NAD+, playing a key role in protecting cells from damage associated with ageing. They actively participate in DNA repair, particularly that which is damaged by UV rays or other environmental factors. For instance, a study in vivo and in vitro, conducted on mammalian cells and mice, revealed that the activation of sirtuins, especially SIRT6, enhances the repair of DNA breaks under oxidative stress, a crucial process for maintaining the integrity of skin cells. Therefore, by activating sirtuins, NAD+ would aid in repairing skin cells and slowing down ageing.

Sirtuins also play a role in preserving telomeres, structures that protect chromosomes, the length of which decreases with age. The activation of these enzymes could maintain the length of the telomeres, which would promote better cellular health and help limit cell senescence. These results suggest that sirtuins could be useful in delaying cellular ageing. However, further studies on the topical application of NAD+ are needed to confirm these effects.

Inflammation is a natural and essential response of the immune system to protect the body against external aggressions, such as infections, injuries or toxins. It manifests itself through typical signs such as redness, heat, swelling and pain in the affected area. Studies have confirmed that by blocking the enzyme Nampt, involved in the synthesis of NAD+, it is possible to reduce oxidative stress, inflammation and DNA damage, in zebrafish models and human 3D organotypic skin models of systemic and persistent skin inflammations of psoriasis. This reduction in oxidative stress and inflammation is linked to the decrease in NAD+ levels, which, when excessively high, can promote the production of reactive oxygen species (ROS) and thus exacerbate inflammation.

However, these negative effects can be reversed through an additional supply of NAD+, which restores balance and supports cellular repair and antioxidant mechanisms. Indeed, optimal levels of NAD+ help to regulate inflammation and mitigate the harmful effects of UV exposure and pollution, by supporting antioxidant and reparative responses.

Furthermore, a study conducted on 10 women aged between 21 and 61 years, suffering from rosacea, demonstrated the effectiveness of the topical application of 1% NADH in vaseline. After just three days of treatment, six of these patients reported a reduction in irritation and burning sensation. After two weeks, a significant improvement was observed in three patients, with over 75% of their papules having flattened and the level of erythema significantly reduced. Five other patients noted an average improvement of about 50% in papule reduction, with a decrease in erythema. These results confirm that NADH, as a topical agent, can not only effectively target inflammatory conditions, such as rosacea and contact dermatitis, but also potentially contribute to preventing premature skin ageing associated with chronic inflammation.

NAD+ is a key component of cellular renewal, essential for maintaining healthy skin. As we age, this process becomes less efficient, leading to an accumulation of dead cells and a loss of radiance. This is where NAD+ steps in to support the regeneration of skin cells. A study conducted on individuals with damaged skin (three distinct cohorts, with respectively 16 participants in study 1, 60 in study 2, and 20 in study 3) revealed that after four weeks, the twice-daily application of a formula containing 5% myristyl nicotinate (MA) increased NAD+ levels in the skin and promoted the regeneration of the epidermis.

MA, a derivative of nicotinic acid, releases nicotinic acid into the skin without causing vasodilation. Through a yet undefined mechanism, this promotes the production of NAD+ by activating enzymes, such as nicotinamide phosphoribosyltransferase, involved in the biosynthesis of NAD+. According to this study, the skin's renewal rate increased by 1 to 6%, while the thickness of the epidermis increased by 20%. As a result, the skin appears to become smoother, less prone to fine lines and blemishes. Furthermore, the study revealed a decrease in transepidermal water loss, suggesting a better water retention.

NAD+ is crucial for maintaining skin health, by supporting cellular functions and mitigating signs of ageing. It promotes cell regeneration and the repair of skin damage, thus helping to maintain radiant and healthy skin. Its use could be a valuable asset in skincare.