Here's what you need to know about curcumin...

1. Curcumin shows anti-catabolic effects.
2. Curcumin can optimize the effects of insulin.
3. Curcumin has been shown to reduce estrogen levels, which could lead to increased testosterone levels.

The anti-catabolic potential of curcumin

Curcumin is known as an anti-inflammatory and pain-relieving supplement, but new scientific research suggests that it may also have anti-catabolic effects, improve insulin sensitivity and may even have androgenic properties.

Studies have shown that curcumin supplementation inhibits protein breakdown after injury and in cachexia (a general physical decline usually associated with chronic disease), suggesting that curcumin does indeed have anti-catabolic properties.

In addition to this, curcumin supplementation after eccentric exercise resulted in a reduced inflammatory response and reduced markers of muscle damage after exercise, while also improving recovery. It has even been shown that curcumin supplementation can reduce muscle atrophy.

Although no study has yet investigated the effects of curcumin on muscle hypertrophy in weight-trained individuals, scientific research suggests that it is entirely plausible that this yellow-colored phenol could have anti-catabolic effects. This means that curcumin supplementation could be useful when it comes to building muscle and post-workout recovery.

Conclusion: Curcumin supplementation appears to have anti-catabolic effects and curcumin could therefore be an effective supplement for promoting muscle growth and recovery.

The anti-inflammatory properties of curcumin

Although a certain amount of inflammatory response is necessary for the healing process, too much inflammation is not desirable and can keep you from training for days, weeks or even months. The scientific literature shows quite clearly that curcumin has anti-inflammatory properties as it inhibits the primary inflammatory pathway (Tnf-α and nF-kB). Even though most of the research on this topic is based on medical applications, these results are also transferable to resistance training.

Curcumin is interesting because it appears to prevent the onset of inflammation and reduce existing inflammation, based on its ability to mimic aspirin as a COX-2 inhibitor. Perhaps the greatest benefit of curcumin's anti-inflammatory properties is its ability to reduce joint inflammation and arthritis. Scientific research has shown that curcumin supplementation can reduce the severity of joint pain in subjects with osteoarthritis and rheumatoid arthritis.

Although not all scientific studies have shown a reduction in markers of joint inflammation, people who suffer from joint pain and supplement with curcumin experience a significant reduction in symptoms.

Conclusion: Curcumin supplementation appears to have anti-inflammatory effects and is effective in reducing symptoms of joint pain, allowing you to improve your exercise performance.

Antioxidant properties of curcumin

The original use of curcumin was as a powerful antioxidant. Supplementing with antioxidants is of course a tricky business, as there is still debate as to whether antioxidant supplementation could reduce exercise effectiveness. Although oxidation of muscle tissue may play a major role in muscle catabolism, exercise-induced oxidation could serve as a hermetic stressor that signals muscles to grow.

However, preventing excessive oxidation may aid recovery and muscle growth, and there is ample evidence from human and animal studies to suggest that curcumin is an effective antioxidant that may help prevent an excessive oxidative environment.

Conclusion: Curcumin is an effective exogenous antioxidant.

Insulin sensitivity enhancing properties of curcumin

Insulin signaling in muscle cells results in muscle protein synthesis. Anecdotal and scientific evidence shows that optimizing insulin signaling after exercise in combination with appropriate carbohydrate and protein consumption results in increased muscle growth.

Of course, like any hormone, insulin signaling is regulated and the anabolic signal is not infinitely strong, but curcumin can help you get a little more anabolic action out of insulin. Curcumin is believed to prevent the negative feedback mechanism that reduces the signaling effects of insulin, suggesting that curcumin may help enhance the anabolic signaling effects of insulin by improving insulin sensitivity.

Conclusion: Supplementation with curcumin may increase insulin sensitivity, suggesting that curcumin may help to enhance the anabolic effects of insulin in skeletal muscle.

Possible properties of curcumin to increase testosterone levels

Testosterone is the king of the world of anabolic hormones. It increases the rate of protein synthesis, it increases lean muscle mass and it promotes overall health and well-being. Although curcumin is touted as a supplement that increases testosterone levels, there is a lack of scientific research to back this up.

At the moment, we know that curcumin has a protective effect on testicular function, particularly in the case of excessive alcohol consumption. In addition to this, scientific studies have shown that curcumin inhibits the conversion of testosterone into the more active androgen DHT (dihydrotestosterone), but due to the extremely high doses used in these studies, it is not particularly likely that this is the case in humans. However, there is some plausible evidence that curcumin may reduce estrogen levels, which would result in an increase in testosterone levels.

Ultimately, the last word on the exact effects of curcumin on testosterone levels in humans has not yet been spoken.

Conclusion: Curcumin supplementation appears to protect testicular function.

Dosage and safety

A recently published meta-analysis that looked at six human studies concluded that curcumin is completely safe and harmless, even at supraphysiologic doses, and that there is no evidence of toxicity. The LD50 dosage (the dosage that is lethal in 50% of the test animals) in mice is above 2000 mg per kilogram of body weight, which, converted to humans, corresponds to an LD50 dosage of 160,000 mg for a man weighing 80 kilograms. Considering that the standard dose of curcumin is between 80 and 750 mg, it is safe to say that curcumin supplementation in this dosage range is safe and harmless.

Conclusion: Curcumin supplementation is safe and harmless at the recommended dosages and side effects appear to be negligible to non-existent.

References

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By Brad Dieter, PhD | 09/19/13