TABLE 3.
Correlation coefficients between niacin intake, tissue and serum retinol, and plasma PLP concentrations1
| Estimated niacin intake | Serum retinol (μmol/L) | Serum retinyl esters (μmol/L) | Liver retinol (μmol/g) | Small intestine retinol (nmol/g) | Plasma PLP (nmol/g) | |
|---|---|---|---|---|---|---|
| Estimated niacin intake | 1.00 | 0.770∗∗ | −0.060 | −0.315∗ | −0.068 | 0.800∗∗ |
| Serum retinol | — | 1.00 | 0.137 | −0.109 | 0.098 | 0.708∗∗ |
| Serum retinyl esters | — | — | 1.00 | 0.755∗∗ | 0.716∗∗ | −0.073 |
| Liver retinol | — | — | — | 1.00 | 0.896∗∗ | −0.279∗ |
| Small intestine retinol | — | — | — | — | 1.00 | −0.028 |
| Plasma PLP | — | — | — | — | — | 1.00 |
1
Values are Spearman correlation coefficients: ∗P < 0.05; ∗∗P < 0.0001.