DIM is present in cruciferous vegetables and further produced after ingestion of crucifers. DIM has been studied for numerous potential health benefits.
PURPOSE: The present investigation sought to evaluate the effects of DIM on resting and exercise metabolism, fasted glucose, blood lipids and estrogen metabolites after 7 days of supplementation.
METHODS: The present investigation was a double-blind, cross-over design. Eight overweight college aged males volunteered to participate (Age: 22±2.9yrs; height: 180.9±7.4; BF%: 34.6±5.8). Participants were given DIM (150mg) or placebo twice daily for seven days before returning to the lab, providing blood and urine samples for analysis, undergoing a resting metabolic rate (RMR) assessment and exercising for 20 minutes at a moderate intensity (50% VO2 peak). Prior to crossing over to the other treatment, subjects had a 7 day washout period.
RESULTS: Paired samples T-test did not reveal differences for total cholesterol (t=0.49, p=032 DIM 149mg/ dL±19.2, placebo 161mg/dL±16.7), triglycerides (t=0.29, p=0.38 DIM 137.6mg/dL±31.2, placebo 149mg/dL±19.5), Fasted Glucose (t=0.03, p=0.55 DIM 101.8mg/dL±6.9, placebo 101.6mg/dL±2.9), RMR (t=0.37, p=0.35 DIM 2756.4 kcal/24hr±226.6, placebo 2796.6 kcal/24hr±161.4). Additionally, there were no significant differences found for exercise respiratory exchange ratio (RER), glucose or lactate between treatments (t<0.86, p>0.36). Urine sample were analyzed for 2-hyrdoxyestrone (2OHE1) and 16 α -hydroxyestrone (16α-OH-E1) levels using a commercially available immunoassay. Analysis of results did not reveal differences for 2OHE1 (F=0.23, p=0.63 DIM 4.58 ng/ml±4.28 vs placebo 3.80 ng/ml±3.18) or 16α-OH-E1 (F=0.001, p=0.93 DIM 13.34 ng/ml±14.24 placebo 13.87 ng/ml±12.83). When examined as a ratio 2OHE1/16α-OH-E1 Anova did reveal a significant increase associated with DIM ingestion (F=2.28, p=0.04, ES=0.67).
CONCLUSION: Based upon the data from the present study supplemental DIM does not appear to alter metabolism at rest or exercise in overweight young men. The higher 2OHE1 to 16-OH-E1 warrants further investigation as this ratio has been associated with positive health outcomes.
