Safety of <7500 RE (<25000 IU) vitamin A daily in adults with retinitis pigmentosa

Abstract

Background: Vitamin A supplementation is being used successfully to treat some forms of cancer and the degenerative eye disease retinitis pigmentosa. The daily biological need for vitamin A is estimated to be 800 retinol equivalents ( Results: Patients in group A showed an 8% increase in mean serum retinol concentration at 5 y and an 18% increase at 12 y (P < 0.001); no retinol value exceeded the upper normal limit (3.49 mol/L, or 100 g/dL). Mean serum retinyl esters were elevated Ϸ1.7-fold at 5 y and remained relatively stable thereafter. No clinical symptoms or signs of liver toxicity attributable to vitamin A excess were detected. Conclusions: Prolonged daily consumption of < 7500 RE (< 25 000 IU) vitamin A/d can be considered safe in this age group.

Effectiveness and safety of nutritional supplements in the treatment of hereditary retinal dystrophies: a systematic review

“…Finally, 8 studies informed in 13 articles were included in the present review. [9][10][11][12][13][14][15][16][17][18][19][20][21] Characteristics of studies…”

“…12 Except Lee et al which studied Best disease, 18 all included studies are on RP. [9][10][11][12][13][14][15][16][17][19][20][21] They assessed supplements based on vitamin A and vitamin E, 12 docosahexaenoic acid (DHA), 9,10,14,16,18 and the carotenoids lutein, 11,13 and β-carotene. 19 We did not identify eligible studies about other HRDs.…”

“…This result at 5 years was also maintained in a 12 years follow-up subsample. 20 The trial by Berson et al on Vitamin A and DHA did not report any adverse effects in the 4 years follow-up period. 14 Similarly, Hoffman et al did not observe severe adverse events, 16 nevertheless an additional publication of this study focusing on biological safety and adverse events reported the occurrence of minor adverse events equally distributed between the DHA and control groups.…”

Vitamin A supplementation reduces the Th17-Treg – Related cytokines in obese and non-obese women

“…Therefore, therapeutic agents which reduce the ATRA as a potent derivate of vitamin A is considered as a therapeutic agent in prevention or treatment of autoimmune disease and several types of cancers (17,18) however its potential adverse effects and lifethreatening complications such as headache, nausea, vomiting, irregular heartbeat, bleeding, liver dysfunction and teratogenicity should not be forgotten (19). In the human body, vitamin A as retinyl palmitate is converted to ATRA by dendritic cells (DC) from mesenteric lymph nodes and Peyer's patches (16) and it capable to suppress carcinogenesis or other degenerative disease with less (20) or no side effects (21,22).…”

Tapetoretinal degenerations: Experiences, experiments and expectations

“…The situation improved when vitamin A (15 000 IU per day) in a rigorously conducted study on 600 patients was reported to have a beneficial effect (Berson 1993;Berson et al 1993Berson et al , 1998, retarding the progression of the disease somewhat (about 8%). Vitamin A is toxic at high doses, but 15 000 IU daily is not likely to have detrimental effects (Sibulesky et al 1999). The mechanism of action of the treatment is not well understood, although there is now support for it also in experimental animals.…”