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Magnesium Ascorbyl Phosphate

Also known as: Magnesium Ascorbyl Phosphate, MAP, Magnesium L-ascorbyl-2-phosphate, Vitamin C phosphate

Overview

Magnesium ascorbyl phosphate (MAP) is a stable, water-soluble derivative of vitamin C (ascorbic acid). Synthesized to overcome the instability of pure ascorbic acid, MAP is not naturally found in foods. It is primarily used in topical skincare for its antioxidant and collagen-promoting properties. Emerging research explores its potential for oral supplementation in bone health. MAP is highly stable, water-soluble, and less irritating to the skin compared to ascorbic acid, while still providing antioxidant and collagen synthesis benefits. Research for topical use is more robust than for oral supplementation, with bone health research being an emerging but limited area. Evidence for topical use is supported by multiple RCTs and systematic reviews, while evidence for oral supplementation is limited to a few high-quality RCTs and preclinical studies.

Benefits

Topical application of magnesium ascorbyl phosphate increases skin antioxidant capacity, reduces oxidative stress, and promotes collagen synthesis. Clinical studies demonstrate improved skin hydration and reduced signs of aging, though effect sizes vary based on formulation and concentration. Orally, a recent systematic review and meta-analysis suggests that MAP promotes bone formation via CaMKII signaling, with preclinical data indicating increased bone mineral density and osteoblast activity. Benefits are most pronounced in individuals with photoaged or dry skin for topical applications. Potential benefits for bone health are indicated in populations at risk for osteoporosis, but human data are currently lacking. Noticeable effects from topical use can be seen within 4–12 weeks of daily use.

How it works

Topically, magnesium ascorbyl phosphate acts as a pro-drug, converting to ascorbic acid in the skin. Once converted, it scavenges free radicals, inhibits melanogenesis, and stimulates collagen synthesis. For bone health, MAP promotes osteoblast differentiation and bone formation via activation of CaMKII signaling pathways. It primarily affects the skin and bone, with systemic effects being less well-characterized. Molecular targets include CaMKII (bone), collagen synthesis enzymes (skin), and antioxidant enzymes. Topical absorption allows penetration into the skin, converting to active ascorbic acid, with tissue levels saturating after several days of application. Oral absorption data is limited but likely similar to other vitamin C derivatives.

Side effects

Magnesium ascorbyl phosphate is generally recognized as safe for topical and oral use at recommended doses. Common side effects are rare, though topical use may cause mild irritation in sensitive individuals. Uncommon side effects have not been reported in clinical studies. Allergic reactions are possible but very rare. No significant drug interactions have been reported, but caution is advised with high-dose vitamin C in individuals on certain medications, such as chemotherapy or anticoagulants. There are no established contraindications, but it should be avoided in individuals with known hypersensitivity to vitamin C or its derivatives. It is considered safe for most populations, but there is insufficient data for pregnant or breastfeeding women.

Dosage

For topical use, the minimum effective dose of magnesium ascorbyl phosphate is 0.1–1% in creams and serums, with an optimal dosage range of 1–3% in cosmetic formulations. Up to 3% is generally well-tolerated. Apply once or twice daily to clean skin. For oral use, there is no established minimum effective dose, optimal dosage range, or maximum safe dose; preclinical studies have used variable doses, and further research is needed. Topical absorption is enhanced by formulation with penetration enhancers. Oral absorption is likely similar to other vitamin C derivatives. No specific cofactors are required, but general antioxidant support may enhance effects.

FAQs

How should I use magnesium ascorbyl phosphate topically?

Apply to clean skin, preferably in the morning or evening. It's best used in stable formulations and is less irritating than pure ascorbic acid. Look for concentrations between 1-3% in creams or serums.

Is magnesium ascorbyl phosphate safe?

Yes, it is generally considered safe at recommended doses, with a very low risk of adverse effects. However, those with known hypersensitivity to vitamin C should avoid it.

What are the expected results from topical use?

Topical application can lead to improved skin hydration, reduced oxidative stress, and modest anti-aging effects. Results are typically noticeable within 4-12 weeks of consistent use.

Is magnesium ascorbyl phosphate a superior form of vitamin C?

Not necessarily. Its main advantage is its stability compared to pure ascorbic acid, making it easier to formulate in skincare products without rapid degradation.

What about oral use for bone health?

There is potential for bone health benefits, but human data are lacking. It is not a substitute for dietary vitamin C, and more research is needed to determine efficacy and optimal dosing.

Research Sources

https://onlinelibrary.wiley.com/doi/full/10.1002/jbmr.4820 – This systematic review and meta-analysis of preclinical studies found that magnesium ascorbyl phosphate promotes bone formation via CaMKII signaling. Preclinical evidence suggests increased bone mineral density and osteoblast activity. However, the review notes the limited availability of human RCT data, highlighting the need for further research to confirm these findings in clinical settings.
https://www.cir-safety.org/sites/default/files/Ascorbic%20Acid.pdf – This safety assessment, based on toxicological and clinical studies, indicates that magnesium ascorbyl phosphate is safe for topical use at concentrations up to 3%. The review also found no significant increase in skin ascorbic acid compared to pure ascorbic acid at equivalent doses. While robust for short-term safety, the assessment acknowledges the need for more long-term data to fully understand potential effects.
https://jhrlmc.com/index.php/home/article/view/1306 – This clinical formulation and stability study demonstrates that magnesium ascorbyl phosphate is stable in topical creams and can be combined with other active ingredients for enhanced skin benefits. The study focuses on formulation development and does not report direct clinical outcomes. It highlights the ingredient's compatibility and stability in cosmetic formulations.
https://journals.sagepub.com/doi/10.1080/10915810590953851 – This study investigates the topical use of magnesium ascorbyl phosphate for skin health. The research indicates that MAP improves skin hydration and provides antioxidant benefits. However, the study also notes limitations related to long-term data and the need for further research to fully understand the ingredient's effects on skin aging.
https://www.chemicalbook.com/article/properties-and-determination-of-magnesium-ascorbyl-phosphate.htm – This resource provides information on the properties and determination of magnesium ascorbyl phosphate. It details the chemical characteristics and methods for analyzing the compound. The resource is useful for understanding the basic science behind MAP and its formulation in various applications.