Vitamin K2 reduced frequency, intensity, duration of nocturnal leg cramps
Vitamin K2 reduced symptoms from nocturnal leg cramps in older patients starting with the first week of its administration in a placebo-controlled randomized trial in China.
Older patients taking vitamin K2 had decreased frequency, shortened duration, and weakened intensity of nocturnal leg cramps, a Chinese study found.
The multicenter, double-blind trial included 199 participants ages 65 years and older (54.3% female; mean age, 72.3 years) in China between September 2022 and December 2023 who had two or more documented episodes of nocturnal leg cramps during two weeks of screening. Eligible patients were randomized to receive vitamin K2 (menaquinone 7), 180 μg, or a similar-looking placebo every day for eight weeks. Results were published Oct. 28 by JAMA Internal Medicine.
Overall, 103 patients (51.8%) were randomly assigned to receive vitamin K2 and 96 (48.2%) were assigned to receive placebo. Both groups had comparable mean frequency of cramps at baseline (2.60 vs. 2.71, respectively). During the eight-week study, the vitamin K2 group's mean (SD) weekly frequency decreased to 0.96 (1.41) while the placebo group's was 3.63 (2.20), a statistically significant difference (−2.67 [95% CI, −2.86 to −2.49]; P<0.001).
Mean reduction in leg cramp severity was more significant in the vitamin K2 group than in the placebo group (−2.55 [SD, 2.12] points vs. −1.24 [SD, 1.16] points). The vitamin K2 group also had a more pronounced mean decrease in duration of cramps (−0.90 [SD, 0.88] min vs. −0.32 [0.78] min). There appeared to be no adverse events related to vitamin K2 use.
“[D]aily vitamin K2 supplementation alleviates muscle cramps in older individuals affected by [nocturnal leg cramps], manifested by decreased frequency, shortened duration, and weakened intensity,” the study authors concluded. “Notably, cramping frequency was significantly reduced compared with the placebo group, starting from the first week of intervention with vitamin K2.”