Serum and Dietary Folate and Vitamin B₁₂ Levels Account for Differences in Cellular Aging: Evidence Based on Telomere Findings in 5581 U.S. Adults

Table 3

Relationship between serum and dietary levels of folate and vitamin B12 (per 10% increase) and telomere length (base pairs) in U.S. women and men.

	Telomere length (base pairs)
Exposure variable	Regression coefficient
Women
Serum folate (ng/mL)
Model 1	9.57	2.75	10.5	0.0030
Model 2	8.75	2.94	8.7	0.0062
Dietary folate (mcg)
Model 1	5.41	2.41	5.0	0.0325
Model 2	5.98	2.89	4.3	0.0479
Serum vitamin B12 (pg/mL)
Model 1	3.48	2.01	2.8	0.1056
Model 2	5.59	3.15	3.1	0.0867
Dietary vitamin B12 (mcg)
Model 1	2.12	1.02	4.3	0.0468
Model 2	1.94	1.17	2.8	0.1080
Men
Serum folate (ng/mL)
Model 1	5.81	3.39	2.9	0.0972
Model 2	4.56	3.35	1.9	0.1838
Dietary folate (mcg)
Model 1	2.27	2.86	0.6	0.4341
Model 2	0.71	2.99	0.1	0.8149
Serum vitamin B12 (pg/mL)
Model 1	-1.92	3.58	0.3	0.5948
Model 2	-2.32	3.59	0.4	0.5227
Dietary vitamin B12 (mcg)
Model 1	0.72	1.66	0.2	0.6665
Model 2	0.16	1.66	0.0	0.9239

SE: standard error. For Model 1, the covariates were age and race. For Model 2, in additional to age and race, the model was adjusted for differences in pack-years of smoking, alcohol use, BMI, total physical activity, hours fasted, diabetes status, and pregnancy status (for women). Interpretation of the regression coefficients is as follows for the first row (Model 1) regarding serum folate (ng/mL) in women: after adjusting for differences in age and race, for each 10% increase in serum folate, telomeres were 9.57 base pairs longer, on average.