Painful period cramps, also known as primary dysmenorrhea, can be more than just a monthly nuisance; they can seriously disrupt daily activities. Many of us rely on painkillers to manage the pain, but there is research showing that Vitamin D can offer an alternative way to ease cramps. In fact, several scientific studies indicate that Vitamin D supplementation significantly reduces the pain intensity of cramps, making it a powerful tool in managing menstrual pain.
What the Research Tells Us
In 2023, a meta-analysis reviewed data from 8 clinical trials involving 695 participants (aged 13 to 40) suffering with painful cramps. Vitamin D supplementation significantly decreased pain intensity compared to a placebo1. This wasn’t an isolated finding: one year later, another meta-analysis confirmed similar results2.
One of the studies looked at some other pain-related measures too. Participants who took Vitamin D for 8 weeks had significant reductions in the number of days with pain and the number of consumed pain-relief medications3. The placebo group didn’t experience improvements in these areas.
The Link Between Vitamin D Deficiency and Cramps
Several studies in this area also measured the participants’ Vitamin D levels, and a recurring theme has emerged: many women suffering from painful cramps have low levels of Vitamin D.
And did know that 74% of people in the UK have suboptimal levels of Vitamin D?4 This means many of us may be more susceptible to experiencing period pain.
A study of 372 participants found a direct link between low Vitamin D levels and the severity of painful periods, suggesting that low Vitamin D might make cramps worse5.
How Exactly Does Vitamin D Help Ease Cramps?
To understand how Vitamin D works its magic, we first need to know what causes cramps in the first place. Just before your period, progesterone levels drop, which triggers the release of prostaglandins - chemical messengers that cause the uterus to contract and shed its lining. These are also responsible for the cramping pain that many of us dread.
Here's how Vitamin D is suggested to reduce prostaglandins in the uterine tissue6-10:
- Reducing Prostaglandin Production: Vitamin D is known to suppress the enzyme COX-2, which is needed to make prostaglandins. Less COX-2 means less prostaglandin production, which in turn leads to less cramping.
- Reducing Sensitivity to Prostaglandins: Vitamin D may indirectly decrease the expression of prostaglandin receptors in the uterus, meaning the uterus becomes less sensitive to prostaglandins and their pain-causing effects.
- Breaking Down Prostaglandins Faster: Vitamin D also helps speed up the breakdown of prostaglandins by increasing the activity of an enzyme called 15-PGDH, which helps clear these chemicals from the body faster.
But that's not all! Vitamin D also plays a role in inflammation, a key factor in the intensity of cramps. Research shows that Vitamin D helps reduce the production of inflammatory cytokines - molecules that promote inflammation and pain11,12. By keeping inflammation in check, Vitamin D can help reduce the overall pain experience during your period.
We also know that Vitamin D receptors (VDRs) are found in the uterine cells and immune cells within the uterine lining (endometrium), which suggests that Vitamin D can act directly within the uterus to help manage pain and inflammation!7,12
How much Vitamin D is Enough?
DITTO's menstrual cycle supplement provides 15 micrograms (600 IU) of Vitamin D3 (the most effective form) per day to help ensure your levels stay optimal for managing period pain.
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Definitions and references for those who want to geek out!
1Chen YC, Chiang YF, Lin YJ, et al. Effect of Vitamin D Supplementation on Primary Dysmenorrhea: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. Nutrients. 2023;15(13):2830.
2Lin KC, Huang KJ, Lin MN, Wang CY, Tsai TY. Vitamin D Supplementation for Patients with Dysmenorrhoea: A Meta-Analysis with Trial Sequential Analysis of Randomised Controlled Trials. Nutrients. 2024;16(7):1089
3Rahnemaei FA, Gholamrezaei A, Afrakhteh M, et al. Vitamin D supplementation for primary dysmenorrhea: a double-blind, randomized, placebo-controlled trial. Obstet Gynecol Sci. 2021;64(4):353-363.
4Data collected by FORTH (www.forthwithlife.co.uk)
5Zeynali M, Haghighian HK. Is there a relationship between serum vitamin D with dysmenorrhea pain in young women?. J Gynecol Obstet Hum Reprod. 2019;48(9):711-714.
6Christakos S, Dhawan P, Verstuyf A, Verlinden L, Carmeliet G. Vitamin D: Metabolism, Molecular Mechanism of Action, and Pleiotropic Effects. Physiol Rev. 2016;96(1):365-408.
7Thota C, Laknaur A, Farmer T, Ladson G, Al-Hendy A, Ismail N. Vitamin D regulates contractile profile in human uterine myometrial cells via NF-κB pathway. Am J Obstet Gynecol. 2014;210(4):347.e1-347.e10.
8Shipton EA, Shipton EE. Vitamin D and Pain: Vitamin D and Its Role in the Aetiology and Maintenance of Chronic Pain States and Associated Comorbidities. Pain Res Treat. 2015;2015:904967
9Miyashita M, Koga K, Izumi G, et al. Effects of 1,25-Dihydroxy Vitamin D3 on Endometriosis. J Clin Endocrinol Metab. 2016;101(6):2371-2379.
10Wang Q, He Y, Shen Y, et al. Vitamin D inhibits COX-2 expression and inflammatory response by targeting thioesterase superfamily member 4. J Biol Chem. 2014;289(17):11681-11694.
11Heidari H, Amani R, Feizi A, Askari G, Kohan S, Tavasoli P. Vitamin D Supplementation for Premenstrual Syndrome-Related inflammation and antioxidant markers in students with vitamin D deficient: a randomized clinical trial. Sci Rep. 2019;9(1):14939.
12Viganò P, Lattuada D, Mangioni S, et al. Cycling and early pregnant endometrium as a site of regulated expression of the vitamin D system. J Mol Endocrinol. 2006;36(3):415-424