Although supplementation with appropriate doses of taurine, a natural amino acid, has been reported to alleviate visual fatigue, its application in functional foods is lacking.
As such, some Chinese researchers have conducted a systematic review to summarize taurine’s mechanisms of action and consumption safety to provide a basis for further development and application of this nutrient.
Normal retinal function is essential for maintaining vision and eye health. Studies show that visual fatigue is mainly caused by a decrease or damage to the function of the retina.
When the eye is overused, excessive metabolic waste accumulates in the eye and this leads to various stress injuries to the retina or macula and damage to nerve cells.
According to research results, taurine has an important protective effect on retinal function. It protects retinal photoreceptors, retinal ganglion cells (RGCs), and retinal pigment epithelium (RPE) cells from damage from oxidative stress, inflammation, apoptosis, and ocular neurotoxicity through various pathways, thereby reducing visual fatigue.
Taurine can be obtained from two sources – endogenous metabolic synthesis in the body and exogenous dietary route.
“Since the amount of taurine synthesized by the human body is not sufficient to meet health needs, it must be obtained through dietary supplements.”the authors wrote.
In addition, numerous studies have shown that taurine depletion can impair retinal function and even lead to serious eye diseases.
“Its depletion increases the susceptibility of the retina to damage from light exposure, as well as glial cell proliferation and oxidative stress in the retina. Taurine supplementation is effective in ameliorating retinal photoreceptor degeneration and retinal and optic nerve damage.
Formulation strategies
The main dietary sources of taurine come from animals, especially seafood, which contain high concentrations of taurine in their organs and tissues.
Algae such as kelp and spirulina and plants such as Ganoderma lucidumBerries, lupines and cordyceps also contain some taurine.
Toxicity studies done on taurine have confirmed that it is not carcinogenic, genotoxic (damages DNA), or teratogenic (something that can cause or increase the risk of a birth defect).
“Taurine The high safety profile allows its addition to functional foods and beverages in many countries. Further research on the synergistic effect of taurine in combination with other ingredients is needed in the future development of functional foods to alleviate visual fatigue. This would help clarify the optimal formulation ratio between taurine and other functional ingredients so as to maximize the benefits of the products,” the authors said.
Furthermore, this review found that chemical synthesis and biofermentation methods are suitable for the industrial production of high-purity taurine, but each has certain drawbacks.
Extraction methods, on the other hand, are not recommended for the industrial production of higher purity taurine, but are of “high importance” for the development of functional food ingredients.
“When taurine-rich food is consumed, digestion, absorption and metabolism must take place to replenish the body with the required amount of taurine. This suggests that not only the level of taurine content in food is important, but also the relationship between dose and efficacy.
“Appropriate selection of ingredients and extraction methods can effectively increase the taurine content of raw materials, improve the utilization of raw materials, improve the novelty of product formulations, and facilitate researchers to diversify the design of dosage forms.” the authors concluded.
Source: Nutrients
https://doi.org/10.3390/nu15081843
“Taurine: Source and Application to Alleviate Visual Fatigue”
Authors: Hao Duan et al.