The Role of Vitamin B6 in Premenstrual Syndrome (PMS): Evidence-Based Insights for Dietitians

Premenstrual Syndrome (PMS) can significantly affect the quality of life in women and people who menstruate. 

Nutrition interventions, particularly the use of Vitamin B6, have gained attention for their potential in managing the symptoms associated with these conditions. 

This article explores the definitions of PMS and PMDD, the role of Vitamin B6, and the latest research on its effectiveness, risks, and recommendations for dietitians.

What is PMS?

Premenstrual Syndrome (PMS) is a collection of physical, emotional, and behavioral symptoms that typically occur during the luteal phase of the menstrual cycle—the phase between ovulation and the onset of menstruation. PMS affects up to 75% of women of reproductive age, though symptoms can range from mild to severe. Symptoms generally resolve with the onset of menstruation.

Symptoms of PMS 

PMS symptoms occur exclusively during the luteal phase and resolve at the start of menstruation. The symptoms can be grouped into physical, emotional, and behavioral categories:

Physical Symptoms of PMS 

• Bloating and water retention 

• Breast tenderness

• Headaches or migraines

• Muscle or joint pain

• Fatigue

• Digestive symptoms like constipation or diarrhea 

• Food cravings and changes in appetite

  
  

Emotional and Behavioural Symptoms of PMS 

• Irritability and mood swings

• Depression

• Anxiety and tension

• Difficulty concentrating

• Sleep disturbances

• Social withdrawal

What is Vitamin B6?

Vitamin B6, also known as pyridoxine, is a water-soluble vitamin that plays a crucial role in numerous bodily functions including neurotransmitter synthesis, hormone modulation, and immune function. 

Dietary Sources of Vitamin B6

Vitamin B6 can be obtained from various food sources:

• Poultry: Chicken and turkey are excellent sources of Vitamin B6

• Fish: Tuna, salmon, and other fatty fish are rich in B6

• Fortified cereals: Many breakfast cereals are fortified with Vitamin B6

• Fruits and vegetables: Bananas, spinach, potatoes, and avocados are plant-based sources of Vitamin B6

Research on Vitamin B6 and PMS/PMDD

Mechanism of Action

Vitamin B6 is essential for the production of neurotransmitters, such as serotonin and dopamine, that play a role in mood regulation. During the luteal phase, the drop in estrogen and progesterone levels can affect serotonin levels, contributing to mood symptoms. Vitamin B6 supplementation may support serotonin production, potentially alleviating some emotional symptoms.

Key Studies on Vitamin B6 and PMS

Systematic Reviews and Meta-Analyses:

• A meta-analysis by Sayehmiri et al. (2016) found that Vitamin B6 significantly reduced both physical and psychological symptoms of PMS compared to placebo 

• Another systematic review conducted by the British Medical Journal (BMJ) concluded that Vitamin B6 doses of up to 100 mg/day are likely to benefit women with PMS, especially those suffering from mood-related symptoms. The authors of the study conclude: Conclusions are limited by the low quality of most of the trials included. Results suggest that doses of vitamin B-6 up to 100 mg/day are likely to be of benefit in treating premenstrual symptoms and premenstrual depression

Randomized Controlled Trials (RCTs) and Observational Studies:

• One double blinded randomized control trial with 160 participants who took 80 mg of vitamin B6 or placebo for 2 cycles showed that Vitamin B6 (80 mg/day) significantly reduced PMS symptoms such as irritability, anxiety, depression, and bloating in a group of university students

• In another double blinded crossover randomized control trial including 63 participants, researchers found that 50 mg/day of Vitamin B6 for 3 months significantly improved emotional symptoms like depression, irritability, and tiredness 

• A case control study within the Nurses’ Health Study II cohort examined the relationship between B vitamin intake and the development of PMS. While Vitamin B6 intake was not associated with the risk of PMS, other B vitamins like thiamine and riboflavin were associated with a lower risk

The quality of studies investigating Vitamin B6 for PMS and PMDD is mixed. Limitations include small sample sizes, inconsistent diagnostic criteria, and incomplete data reduce the strength of these findings. More high-quality, up-to-date research is needed to confirm its efficacy, explore long-term safety, and provide clearer guidance on optimal dosages.

Risks of High-Dose Vitamin B6

Although Vitamin B6 is generally safe at low doses, high doses can pose a risk of peripheral neuropathy at doses above 100 mg/day. 

This condition is usually reversible upon discontinuation of high-dose supplementation. It is recommended that adults should not exceed 100 mg of Vitamin B6 daily.

Practice Recommendations for Dietitians

Dietitians can play a crucial role in helping women manage PMS and PMDD through dietary and supplemental interventions. Here are some evidence-based recommendations:

Encourage a diet rich in Vitamin B6:

• Advise clients to consume Vitamin B6-rich foods such as poultry, fish, fortified cereals, and vegetables

Be transparent about the current research:

• Share the current state of research on Vitamin B6, highlighting that while evidence suggests it may alleviate mood-related symptoms of PMS, many studies are outdated or have methodological limitations

• For clients experiencing symptoms that significantly disrupt daily life, it’s important to consider other evidence-based solutions that may provide faster or more reliable improvements

Educate clients on the risks of over-supplementation:

• Discuss the potential risks of taking high-dose Vitamin B6 without professional guidance. Let clients know that doses up to 100 mg/day are safe, but higher doses should be taken with caution

Conclusion

Vitamin B6 may be a cost-effective and beneficial treatment for managing emotional symptoms of PMS, particularly at doses of up to 100 mg/day. However, the current research is lacking in quality. 

Further research is needed to fully understand the long-term efficacy and safety of Vitamin B6 supplementation in women with PMS.