Table 2.

Studies connecting Vitamin C, E, A, alpha and beta-carotene with spirometric values improvement.

Vitamin	FFQ studies	Plasma levels studies	Improvement in spirometric values	No association with spirometric values
Vit C	31,58,59,60,61, 62,63,65,66	32,52, 63,69,70	Serum:FEV1 improvement in ml from 17-94 ml and FVC improvement from 16.4-94 ml for an SD variation FFQ: FEV1 improvement in ml from 37-53 ml and FVC improvement from 23.3-79 ml for an SD variation	52
Vit E	31,58,59,61, 62,64,65	32,69,70	Serum: An SD increase in plasma levels of vitamin E had a median range of FEV1 increase in ml from 12-59.3 ml FFQ: An SD increase had a median range of FEV1 increase in ml from 20.1-93 ml and for FVC from 23.1 -54 ml, respectivelly	31,58,61
Vit A	61,68	32,70	32,70 Serum:Improvement in FEV1 ranges from 22-31.2 ml	61,68
b-carotene	31,57, 63,65,66,69	32,69, 70, 76	Serum: Improvement in FEV1 ranges from 11-107 ml, FVC 147 ml FFQ: Improvement in FEV1 = 60 ml, FVC= 75 ml	57
a-carotene		70,71	70,71 Serum: Improvement in FEV1 for one SD increase 23.7 ml70. Subjects in the fifth quintile of serum beta-carotene had a 195 ml (95% confidence interval [95% CI]: 40 to 351 ml) higher and those in the fifth quintile of alpha-carotene had a 257 ml (95% CI: 99 to 414 ml) higher FEV(1) compared with subjects in the first quintile of these carotenoids71.