Heppner KM, Kirigiti M, Secher A, Paulsen SJ, Buckingham R, Pyke C, et al
Adequate B12 levels can help preserve the health and integrity of the nervous system, promoting optimal nerve transmission and reducing the risk of neurological disorders
The effect was abolished in PepT1-knockout mice, confirming the transport pathway (PMC4957955)
When it was recognized that pellagra, a condition marked by diarrhea, dermatitis, dementia, and mortality, could be treated with foods containing NAD+ precursors, particularly vitamin B3, the clinical significance of maintaining NAD+ levels was established in the early 1900s (9). Notably, the skin does not flush with NAD+ injection, in contrast to vitamin B3 (niacin) intake, which also causes this negative effect (10). Low NAD+ levels have recently been associated with a variety of age-related ailments and diseases linked to increased oxidative/free radical damage, including diabetes, heart disease, vascular dysfunction, ischemic brain injury, Alzheimers disease, and vision loss (8, 11-17)
Another beneficial effect of glutathione is diuretic and helps in coping with heart problems (3)
Alternatively, if you experience mild gastric discomfort, you can take both after a light meal but avoid high-fat foods which can slow absorption
