Vitamin B6, also known as pyridoxine (notably, pyridoxamine HCl is a less common form), has been investigated for its potential role in alleviating symptoms of premenstrual syndrome (PMS), including PMS Type C, which is primarily characterized by cravings, increased appetite, and weight gain. The rationale for its use lies in B6’s function as a coenzyme in neurotransmitter synthesis, particularly serotonin and dopamine, which may affect mood and appetite regulation. Several randomized controlled trials and systematic reviews have assessed the efficacy of vitamin B6 in reducing PMS symptoms overall, with some reporting modest benefits over placebo, particularly for mood-related symptoms. However, the evidence is inconsistent and often limited by small sample sizes, methodological weaknesses, and variations in dosing and forms of B6 used. A 1999 meta-analysis suggested a slight improvement in overall PMS symptoms with B6 supplementation, but the quality of evidence was low to moderate. Specific evidence for vitamin B6’s effect on PMS Type C symptoms (cravings and weight gain) is limited and largely extrapolated from studies on general PMS populations rather than targeted research.

In summary, while there is some scientific rationale and low-to-moderate quality evidence supporting the use of vitamin B6 for general PMS symptoms, strong evidence specifically for PMS Type C is lacking. The benefit appears to be modest at best, and further high-quality, targeted research is needed.