Blood test explanation - Vitamins

Vitamins

Also including the vitamin B₁₂)-related enzyme homocysteine.

Test	Patient type	Standard range		Unit	Optimal range
		Lower limit	Upper limit		Lower limit	Upper limit
Vitamin A		30[15]	65[15]	µg/dL
Vitamin B9 (Folic acid/Folate) - Serum	Age > 1year	3.0[116]	16[116]	ng/mL or μg/L	5[117]
		6.8[118]	36[118]	nmol/l	11[118]
Vitamin B9 (Folic acid/Folate) - Red blood cells		200[116]	600[116]	ng/mL or μg/L
		450[118]	1400[118]	nmol/L
	Pregnant			ng/mL or μg/L	400[116]
				nmol/L	900[116]
Vitamin B12 (Cobalamin)		130,[119] 160[120]	700,[119] 950[120]	ng/L
		100,[121] 120[3]	520,[121] 700[3]	pmol/L
Homocysteine -more detailed ranges in Homocysteine article		3.3[122], 5.9[122]	7.2[122], 15.3[122]	μmol/L		6.3[56]
		45[123], 80[123]	100[123], 210[123]	μg/dL		85[56]
Vitamin C (Ascorbic acid)		0.4[15]	1.5[15]	mg/dL	0.9[56]
		23[124]	85[124]	μmol/L	50[56]
25-hydroxycholecalciferol (a vitamin D)		8,[15][105] 9[105]	40,[105] 80[15]	ng/mL	30,[108] 40[109]	65,[109] 100[108]
		20,[106] 23[107]	95,[107] 150[106]	nmol/L	85,[56] 100[109]	120,[56] 160[109]
Vitamin E				μmol/L	28[56]
				mg/dL	1.2[56]