Table 4.

Most relevant studies (alphabetically sorted by nutritional supplementation type) in diabetic retinopathy, glaucoma and ocular surface disorders/dry eye disease.

Diabetic Retinopathy
Oral Supplementation	Year	Authors	N	Follow-Up	Results of Intervention
Complex formula [DiVFuSS formula]	2016	Chous et al. [167]	67	6 months	Improvement in visual function without macular thickness change.
Complex formula [Vitalux Forte®]	2011	Garcia-Medina et al. [165]	105	5 years	Visual acuity unchanged. Slower progression of treated group.
Lutein and zeaxanthin	2011	Hu et al. [166]	90	3 months	Better visual acuity, contrast sensitivity and decrease of foveal thickness.
Vitamin E	1999	Bursell et al. [164]	45	8 months	Improvement of retinal blood flow after supplementation.
Antioxidants, Carotenoids, Trace metals and Omega 3 Fatty Acids [Nutrof Omega ® formula]	2015	Roig-Revert et al., VSDR group [40]	360	18 months	Decreased plasmatic oxidative level and increased antioxidant activity was seen in T2DM patients.
Antioxidants, Carotenoids, Trace metals and Omega 3 Fatty Acids [Nutrof Omega ® formula]	2020	Sanz-González et al. VSDR group [154]	575	38 months	Reduced oxidative load and dietary prophylaxis/adjunctive intervention for patients at risk of diabetic retinopathy.
Glaucoma
Oral Supplementation	Year	Authors	N	Follow-Up	Results of Intervention
AREDS-based formulas	2015	Garcia-Medina et al. [171]	117	2 years	No differences in visual field indexes, RGCl complex, peripapillary retinal nerve fiber layer.
Black currant anthocyanins	2012	Ohguro et al. [168]	38	24 months	Better mean deviation change (visual field index) in supplemented group.
Black currant anthocyanins	2013	Ohguro et al. [169]	21	4 weeks	IOP decrease at 2 and 4 weeks in treated group but no change in placebo group.
Docosahexaenoic acid	2018	Romeo Villadoniga et al. [173]	47	6 months	IOP decrease at 3 and 6 months in treated eyes.
Formula containing forskolin, homotaurine, carnosine, and folic acid	2016	Mutolo et al. [172]	44	1 year	IOP lowering, ERG improvement and foveal sensitivity.
Antioxidants and Omega 3 fatty acids [Brudysec ® formula]	2013	Galbis-Estrada et al. [45]	97	3 months	Reduced inflammation biomarkers in glaucomatous tears.
Ginkgo biloba extract	2013	Lee et al. [170]	42	12 years	Slower progression of visual field damage in treated patients.
Ocular Surface Disorders/Dry Eyes
Omega 3 and Omega 6 polyunsaturated fatty acids	2019	Downie et al. [174]		4214	Cochrane systematic review of clinical trials evidence uncertain/inconsistent for DEDs.
Omega 3 and Omega 6 polyunsaturated fatty acids	2014	Liu and Ji, [175]		790	Meta-analyses of randomized, placebo-controlled studies. Improvement of clinical tests, individual-reported symptoms in DEDs.
Antioxidants and Omega 3 fatty acids [Brudysec ® formula]	2013	Pinazo-Duran et al. [44]		66	Benefit DED patients. Improvement of dry eye-related quality of life. Ameliorating clinical tests and tear expression of inflammatory mediators.
Antioxidants and Omega 3 fatty acids [Brudysec ® formula]	2015	Galbis-Estrada et al. [123]		90	Improvement of subjective dry-eye symptoms by changing the tear metabolomic profile
Omega 3 fatty acids [Brudy Derm Dry Eye Gel ®]	2021	Pinazo-Durán et al. [177]		72	Ameliorating ocular surface relief and decreasing cytokine expression in tears from contact lenses users.