Here's what you need to know...
- Curcumin displays anti-catabolic effects.
- Curcumin can optimize the effects of insulin.
- Curcumin has been shown to reduce estrogen levels, which could lead to increased Testosterone levels.
Curcumin is widely known as an anti-inflammatory and pain reliever, but new scientific evidence shows that it may also be anti-catabolic, insulin sensitizing, and even androgenic.
Studies have shown that curcumin supplementation inhibits protein degradation after injury and in cases of cachexia (general wasting usually associated with chronic illnesses), suggesting that curcumin does indeed display anti-catabolic effects.
Additionally, curcumin supplementation following eccentric exercise led to reduced post-exercise inflammation and markers of muscle damage while also improving exercise recovery. It's even been shown to reduce muscle atrophy in the presence of deloading.
While no research has examined the effects of curcumin in muscle hypertrophy with weightlifting humans, research has indicated it's entirely plausible that the yellow-colored phenol may have an anti-catabolic effect. This means that curcumin supplementation may be beneficial in adding lean mass and recovering from exercise.
Conclusion: Curcumin supplementation appears to exert anti-catabolic effects, thus it may be an effective supplement in promoting muscle growth and recovery.
While some inflammation is necessary to heal, too much is bad news and can put you out of the training game for days, weeks, or even months. The literature is quite clear that curcumin has anti-inflammatory properties by inhibiting the major inflammatory pathway (Tnf-α and nF-κB). While the majority of the research is based upon medical applications, the research still applies to resistance training.
Curcumin is interesting in that it appears it can prevent the onset of inflammation and reduce current inflammation due to curcumin's ability to mimic aspirin as a COX2 inhibitor. Perhaps the biggest benefit of curcumin's anti-inflammatory properties lies in its ability to reduce joint inflammation and arthritis. Research has shown that supplements containing curcumin reduce the severity of joint pain in individuals with osteoarthritis and even in those with rheumatoid arthritis.
While the evidence doesn't uniformly show a reduction in measurable markers of joint inflammation, individuals with joint pain that supplement with curcumin notice a marked reduction in symptoms.
Conclusion: Curcumin supplementation appears to exert anti-inflammatory effects and is efficacious in reducing symptoms of joint pain, thus enhancing your training.
Perhaps the original use for curcumin was as a potent anti-oxidant. Of course, supplementing with anti-oxidants is a tricky business as there's still some debate as to whether supplemental anti-oxidants may actually reduce the training effect. While oxidation of muscle tissue can play a large part in muscle catabolism, exercise induced oxidation may serve as a hermetic stressor that signals muscle growth.
Still, preventing excess oxidation can help aid recovery and muscle growth, and there's ample evidence in both humans and animals that curcumin is an effective anti-oxidant that may help prevent an excessively oxidative environment.
Conclusion: Curcumin supplementation is an effective exogenous anti-oxidant.
Insulin signaling in the muscle cells results in muscle protein synthesis. Anecdotally and scientifically, optimizing insulin signaling post-workout with proper carbohydrate and protein ingestion results in greater muscle growth.
Of course, like any hormone, the signaling of insulin is regulated and the anabolic signal isn't infinite, but curcumin may actually help you squeeze a little more anabolic action out of insulin. It's believed that curcumin prevents the negative feedback mechanism that reduces insulin signaling, suggesting that curcumin may be beneficial in increasing the anabolic signaling effects of insulin by increasing insulin sensitization.
Conclusion: Curcumin supplementation may increase insulin sensitivity, suggesting it may help increase insulin's anabolic action in skeletal muscle.
Testosterone is the king in the world of anabolic hormones. It drives muscle protein synthesis, increases lean mass, and promotes overall health and well-being. While curcumin has been touted to increase Testosterone levels, the research is lacking.
Currently, we do know that curcumin has a protective effect on testicular function, especially in the case of excess alcohol consumption. Also, high intakes of curcumin have been reported to inhibit the conversion of Testosterone to the more active androgen, DHT, but the likelihood of this being true in humans is low given that the research involved extremely high doses. There is some plausible evidence, though, that low doses of curcumin may reduce estrogen levels, which would have the effect of raising Testosterone levels.
Regardless, the jury is still out on the exact effect of curcumin on Testosterone in humans.
Conclusion: Curcumin supplementation appears to protect testicular function.
A recent meta-analysis of six human trials found curcumin to be completely safe and even supraphysiological doses of curcumin showed no toxicity. The LD50 (lethal dose) has been found to be >2000mg/kg in mice, which if accurate and extrapolated to humans puts the LD50 for a 175-pound male at around 160,000 mg. Given that the standard dose for curcumin is between 80-750mg, it's safe to say that curcumin supplementation is safe in prescribed doses.
Conclusion: Curcumin supplementation is safe in the recommended doses and side effects appear to be negligible or non-existent.
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