Vitamin A5
A New Vitamin for Physical and Mental Balance?
Vitamin research is constantly evolving, and from time to time, exciting new concepts emerge. One of these is the so-called Vitamin A5, which has attracted increasing scientific attention in recent years. But what exactly is behind it? Is it truly a new vitamin, and what potential effects could it have on our body and overall well-being?
What Is Vitamin A5?
Vitamin A5 is a newly proposed member of the vitamin A family, based on the compound
9-cis-13,14-dihydro-retinoic acid (9CDHRA).
This compound has been identified as a naturally occurring signaling molecule in the body that may play an important role in cellular communication. Of particular interest is its function as a ligand for the Retinoid X Receptor (RXR)—a key regulator involved in numerous biological processes, including gene expression, cellular differentiation, metabolism, and immune function.
The idea behind Vitamin A5:
In addition to the well-known forms of vitamin A (e.g., retinol), there may be another, previously underestimated active form of the vitamin.
Scientific Development—From Discovery to Hypothesis
1. The Postulation (2018)
Rühl and colleagues were the first to identify 9-cis-13,14-dihydroretinoic acid (9CDHRA) as an active RXR ligand and proposed that it could serve as the basis for a new vitamin category, which they termed Vitamin A5.
Key message: There may be a biologically relevant retinoid that has been overlooked until now.
2. The “Vitamin A5/X” Concept (2021)
In another study, the concept was expanded:
Vitamin A5 is described as part of a “food-to-lipid-hormone” system
This means: absorption through food → conversion into a hormone-like signaling molecule
Key message: Vitamin A5 may represent a bridge between nutrition and hormonal regulation, highlighting a potential link between dietary components and the body’s signaling pathways.
3. Initial Dietary Recommendations (2023)
Recent studies discuss:
Possible intake levels
Provitamin A5 precursors in foods
The question of whether current dietary recommendations are incomplete
Key message: Vitamin A5 could be integrated into dietary plans over the long term.
4. Expansion of the Vitamin A Classification System
Other studies suggest:
The proposal to classify Vitamin A5 aims to expand the traditional Vitamin A family (A1–A4) and establish Vitamin A5 as a new functional category.
👉 Key message: Our understanding of vitamins could expand.
5. Possible Deficiencies and Mental Health
The discussion surrounding a possible vitamin A5 deficiency is particularly intriguing:
Connection to Brain Function
‘s Potential Role in Mental Health and Mood
Key massage: Vitamin A5 may be a previously underestimated factor in mental well-being.
What Effects Could Vitamin A5 Have?
Although much of the research is still in its early stages, several potential areas of action have already been identified:
Brain & Mental Balance
- Impact on neural signaling pathways
- Possible role in mood and cognitive function
Cell Regulation
- Regulation of Gene Activity via RXR Receptors
- Effects on Cell Growth and Differentiation
metabolism
- Involvement in key metabolic processes
- Possible effects on energy balance and lipid metabolism
Immune System
indirect role through interaction with regulatory receptors
What is the current status?
As promising as the concept is, it’s important to clearly define it:
- Vitamin A5 has not yet been officially recognized as a vitamin
- There are no approved reference values or health claims
- To date, research has been based primarily on:
– biochemical data
– animal models
– initial theoretical concepts
In short: An exciting scientific approach—but not yet an established nutrient category
Conclusion
Vitamin A5 is a prime example of modern nutritional research:
It illustrates just how complex and dynamic our understanding of nutrients is.
Studies to date suggest that:
- new bioactive compounds can be discovered
- Diet and hormonal regulation are more closely linked than previously thought
- and, in particular, places greater emphasis on mental health
