Table 1.

Characteristics of Included Studies

Study ID	Characteristics of populationa	Study designb	Treatment/controlc	Biomarkers of oxidative stress; other clinical outcomes
Collins et al.27	Spain; 40 healthy subjects (age 25–45, BMI n.a.)	Randomized placebo-controlled four-group parallel trial; 84 days	T1 (n=10): 15 mg α- and β-carotene T2 (n=10): 15 mg lutein T3 (n=10): 15 mg lycopene (containing 10% β-carotene) C (n=10): placebo (0 mg lycopene in corn oil)	DNA damage; n.a.
Carroll et al.28	Ireland; 58 elderly volunteers [age 70±5 (63–83), BMI 26.5]	Randomized placebo-controlled double blind three-group parallel study; 84 days	T1 (n=16): 13.3 mg lycopene (with 3.5 mg α-tocopherol and 2.5 mg γ-tocopherol) T2 (n=15): 11.9 mg carotene C (n=16): placebo 0 mg (0.5 g corn oil, 0.06 mg a-tocopherol, and 0.23 mg γ-tocopherol)	Lipid oxidation; n.a.
Hininger et al.29	Spain; 175 healthy nonsmoking males [age 32.8 (25–45), BMI 28.5]	Randomized single-blind placebo-controlled four-group parallel trial; 84 days	T1 (n=35): 15 mg β-carotene T2 (n=45): 15 mg lutein T3 (n=52): 15 mg lycopene (containing 10% β-carotene) C (n=52): placebo 0 mg	Lipid and protein oxidation, antioxidative enzymes; n.a.
Kucuk et al.30	United States; 26 men with newly diagnosed prostate cancer [age 61 (51–71), BMI n.a.]	Randomized two-arm parallel trial; 21 days	T (n=15): 30 mg lycopene (Lyc-o-Mato® capsule) C (n=11): no placebo capsule while increasing daily fruit and vegetable intake	DNA damage; prostatic pathologic evaluation, PSA
Briviba et al.31	Germany; 30 nonsmoking and 25 smoking males (age 34.2, BMI n.a.)	Randomized double-blind placebo-controlled two-group parallel trial; 14 days	T (n=27): 14.6 mg (each capsule contained 4.88 mg lycopene, 0.48 mg phytoene, 0.44 mg phytofluene, and 1.181 mg α-tocopherol.) C (n=28): placebo 0 mg	DNA damage; immune response (lymphocyte proliferation, NK cells activity, IL-2, IL-4, and TNF-α production)
Riso et al.32	Italy; 26 healthy men and women (age 25.8, BMI 21.0)	Random placebo-controlled, double-blind two-group crossover study; 26 days for each period	T (n=13): Lyc-o-Mato drink (5.7 mg of lycopene, 3.7 mg of phytoene, 2.7 mg of phytofluene, 1 mg of β-carotene, and 1.8 mg α-tocopherol) C (n=13): placebo drink devoid of carotenoids	DNA damage; immune/inflammatory factors (TNF-α and interferon-γ production)
Zhao et al.33	United States; 37 healthy, nonsmoking postmenopausal women [age 59.6 (50–70), BMI 25.5]	Randomized double-blind placebo-controlled five-group parallel trial; 56 days	T1 (n=8): 4 mg of lutein, β-carotene, lycopene T2 (n=8): 12 mg lycopene (pure lycopene beadlets) T3 (n=8): 12 mg lutein T4 (n=7): 12 mg β-carotene C (n=6): placebo 0 mg	DNA damage; n.a.
Neyestani et al.34	Iran; 35 patients with T2DM of both sexes (age 54±9, BMI 28.0)	Randomized placebo controlled double blind two-group parallel study, age- and sex-matched; 60 days	T (n=16): 10 mg lycopene C (n=19): placebo 0 mg	Plasma antioxidative capability; IgG
Devaraj et al.35	United States; 82 healthy subjects with mildly elevated cholesterol levels [age 50.6 (≥40), BMI 25.78]	Randomized placebo-controlled four group parallel trial; 56 days	T1 (n=21): 6.5 mg lycopene (purified lycopene with 5% ascorbyl palmitate and 1.5% dl-α-tocopherol) T2 (n=17): 15 mg (as T1) T3 (n=21): 30 mg (as T1) C (n=18): placebo 0 mg (with 5% ascorbyl palmitate and 1.5% dl-α-tocopherol)	DNA damage, lipid oxidation; lipid profile
Talvas et al.36	France; 30 healthy, nonsmoking men [age 60.8 (50–70), BMI 25.8 (24–28)]	Randomized placebo-controlled two-group parallel trial; 7 days	T (n=15): 16 mg (purified lycopene) C (n=15): placebo 0 mg	Plasma antioxidative capability, DNA damage; PSA level
Mackinnon et al.26	Canada; 60 postmenopausal women [age 55.16 (50–60), BMI 25.85]	Randomized placebo-controlled four-group parallel trial; 120 days	T1 (n=15): regular tomato juice T2 (n=15): lycopene-rich tomato juice T3 (n=15): 30 mg lycopene capsule (Lyc-OMato® capsules) C (n=15): placebo 0 mg	DNA damage, lipid and protein oxidation, plasma antioxidative capability; bone resorption marker NTx
Kim et al.37	Korea; 126 healthy men [age 34.15 (22–57), BMI 24.76]	Randomized double-blind placebo-controlled three-group parallel trial; 56 days	T1 (n=41): 6 mg lycopene (Lyc-OMato® capsules,<0.2% β-carotene,>1.5% tocopherols,>1.0% phytoene and phytofluene) T2 (n=37): 15 mg lycopene (as T1) C (n=38): placebo 0 mg capsule of soybean oil	DNA damage, antioxidative enzymes; endothelial cell function (RH-PAT, hs-CRP, systolic blood pressure, sICAM-1, and sVCAM-1)
van Breemen et al.38	United States; 105 African American male veterans [age 66.9±7.5 (50–83), BMI 28.5±5.3]	Randomized, double-blind, placebo-controlled two-group parallel study; 21 days	T (n=54): 30 mg lycopene (LycoRed capsule: 2% plant sterols, 1.5% tocopherols, 1.0% phytoene and phytofluene, and 0.2% β-carotene) C (n=51): placebo 0 mg (capsule of soybean oil)	DNA damage, lipid oxidation; n.a.

^aCountry where study was conducted; number and composition of subjects; age (years); BMI (kg/m²). Values are reported as mean±SD and/or range.

^bType of study; study duration (days).

^cSample sizes; intervention measures (daily dosages).

n.a., not available; T, treatment groups; C, control group; PSA, prostate specific antigen; NK, natural killer; IL, interleukin; TNF-α, tumor necrosis factor alpha; Ig, immunoglobulin; NTx, N-telopeptide; RH-PAT, reactive hyperemia peripheral arterial tonometry; hs-CRP, high sensitive C-reactive protein.