Acceptability, Safety, And Efficacy Of Oral Administration Of Extracts Of Black Or Red Maca (Lepidium Meyenii) In Adult Human Subjects: A Randomized, Double-Blind, Placebo-Controlled Study

Effect Decrease
Values Figure 5
Trial Design Randomized trial
Trial Length 1-6 months
Number of Subjects 197
Sex Both Genders
Age Range 18-29, 30-44, 45-64, 65+
Notes for this study:
In a randomized, double-blind, placebo-controlled trial, 197 participants were allocated to take 3 g of red maca, black mac, or placebo daily for 12 weeks. The researchers took care to distinguish between those who lived at high altitudes and those who lived at low altitude, with 94 of the former and 99 of the latter.

Sexual desire was only increased more than placebo in the red maca group, not the black maca, after 12 weeks, both in those at high and low altitudes. Mood improved in both at low altitude, with a greater improvement in the red maca group, while there wasn't much of a difference between groups after 12 weeks at high altitude. However, red maca showed greater improvements after the first two weeks. The perception of increased energy increased in both maca groups, with a greater increase in the red maca group, while there wasn't a statistically significant difference at high altitude. Quality of life for the Heath-Related Quality of Life Score improved similarly in both maca groups and at both high and low altitudes.

There were possibly some reductions in blood sugar compared with placebo in the high-altitude group, but there were no statistically significant differences. There were no statistically significant differences between placebo and maca for blood pressure. Hemoglobin was unaffected at low altitude, and at high altitude, the maca groups saw a greater reduction than the placebo group, which was statistically significant for black maca. Mountain sickness was reduced more in the maca groups than the placebo group, but the difference was only statistically significant after 4 weeks in the black maca group and was statistically significant the whole time for the red maca group.