Twin clinical trials detected antidepressant effects and reduced diabetes risk: Evidence review affirms curcumin's mood promise
Given America’s alarming and rising rate of diabetes, we need all the allies we can get.
One possible partner is curcumin, the powerfully antioxidant pigment that gives turmeric its orange-yellow hue.
Clinical-trial results reported over the past several years reveal that curcumin holds real promise against the disease.
Depression is another serious and growing problem, and curcumin appears to alleviate this mood disorder.
Let’s look at the ways in which curcumin could serve as a valuable ally against both conditions.
First, we’ll examine curcumin’s salutary effects on chronic inflammation — a risk factor common to both diseases — which at least partially explain the turmeric pigment’s healthy promise.
Curcumin versus inflammation: A driver of diabetes and depression
Oxidative stress results from an excess of uncontrolled free radicals in the body.
Inflammation also produces oxidative stress, which further promotes the inflammation.
In turn, chronic inflammation promotes and worsens diabetes, heart disease, dementia, and autoimmune disorders, among other conditions.
Unfortunately, the excess of sugars and sugary carbohydrates in the standard American diet — and lack of omega-3 fats and colorful, antioxidant-rich plant foods — promotes oxidative stress and chronic inflammation.
As we reported in Curcumin: Miracle or Myth?, the turmeric extract rose to prominence more than 20 years ago, when University of Texas scientists discovered curcumin’s potent antioxidant/anti-inflammatory benefits, produced via its “nutrigenomic” effects on our genes.
Those effects suggest that curcumin might offer exceptionally broad health benefits, given the key role that inflammation plays in virtually every major disorder.
A joint American-Iranian team explored and affirmed that promise in a recent paper, titled “Therapeutic Effects of Curcumin in Inflammatory and Immune-Mediated Diseases: A Nature-Made Jack-of-All-Trades?” (Abdollahi E et al. 2017)
They noted that — in animal and human studies alike — curcumin beneficially affects a wide variety of immune-system cells, thanks in part to its effects on relevant genes.
As they wrote, curcumin’s broadly beneficial genetic and immune-system effects result in “decreasing severity of various diseases”.
And three years ago, scientists from the Virginia Commonwealth University School of Medicine reported that oral curcumin kept pro-inflammatory toxins from slipping through the animals’ gut walls and into their bloodstreams … see Curry Color Tightened Rodents' Gut Barrier to Bacterial Toxins.
So-called "leaky gut" syndrome is now blamed for triggering and/or worsening a wide variety of health problems — so this property adds another benefit to curcumin's unusually broad roster.
Curcumin versus depression: New trial and review add evidence
Evidence that curcumin might help prevent or alleviate depression emerged several years ago.
For example, see Curcumin Tied with Prozac in Depression Trial, Curcumin Enhanced Seniors' Brains, Mood, and Energy, Turmeric Targets Stubborn Depression, and Curcumin May Curb the Fearful Memories that Fuel PTSD.
Study #1 - Australian clinical trial sees antidepressant curcumin benefits
Recently, Australian researchers reported more clinical evidence of curcumin’s antidepressant potential (Lopresti AL et al. 2017).
Scientists at Murdoch University recruited 123 people with major depression for a randomized, double-blind, placebo-controlled clinical trial that lasted 12 weeks.
Importantly, they used a highly absorbed curcumin extract called BCM-95.
That’s a critical distinction, because standard curcumin extracts are very poorly absorbed, and don’t provide a good test of its real potential.
The trial participants were assigned to one of four groups for the 12-week study:
• Placebo capsules
• Curcumin extract (250mg)
• Curcumin extract (500mg)
• Curcumin extract (250mg) plus saffron (15mg)
All three active treatments produced considerable improvements, compared to the placebo group.
And as seen in a prior Australian trial, curcumin was especially effective against so-called “atypical” depression, which can resist treatment with standard therapies.
As they wrote, “Active drug treatments also had greater efficacy in people with atypical depression compared to the remainder of patients (response rates of 65% versus 35% respectively).”
Surprisingly, the lower dose of curcumin worked as well as the higher dose, and it worked as well as the combination of curcumin and saffron. (Saffron also holds considerable promise as an antidepressant "nutraceutical".)
The authors suggested two possible reasons for the apparent lack of difference among the two treatment groups:
• The antidepressant effects of curcumin and saffron don’t grow at higher doses.
• The trial was too small to detect efficacy differences among the active treatments.
The promise of curcumin against depression was also supported by the authors of a recent evidence review.
Study #2 - Evidence review affirms the promise of curcumin versus depression
Last month, scientists from universities in Singapore and Australia published their review of the clinical evidence regarding curcumin as a treatment for depression.
They searched the medical literature for reasonably well-designed, placebo-controlled clinical trials that tested curcumin against depression (Ng QX et al. 2017).
They found and analyzed six clinical trials involving a total of 377 participants, and as they wrote, their review supported the “significant clinical efficacy of curcumin in ameliorating depressive symptoms.”
Encouragingly, they also detected “significant anti-anxiety effects” in three of the trials, with no adverse side effects reported.
Because the studies they examined only lasted four to eight weeks, they couldn’t come to any conclusions concerning the long-term efficacy of curcumin in major depression.
Curcumin versus diabetes: The promise grows
Five years ago, scientists from Thailand reported the results of a clinical trial among people diagnosed with pre-diabetes, in which curcumin curbed progression to diabetes … see Curry Color May Deter Diabetes.
And Iranian researchers recently reported that supplemental curcumin reduced oxidative stress in people diagnosed with diabetes.
The placebo-controlled Iranian trial involved 118 diabetics, and lasted 3 months (Panahi Y et al. 2017).
The Iranian team found that supplemental curcumin reduced a key sign of oxidation — blood levels of MDA — by almost 22%.
In addition, curcumin boosted both the “total antioxidant capacity” of the participants’ blood by 11.6%, and raised their blood levels of an enzyme called SOD — one of the body’s most important internal antioxidants, by 21.1%.
In contrast, the people in the control group saw no reduction in MDA (oxidation) levels, while their blood antioxidant capacity and SOD levels dropped by 17% and 12.6%, respectively.
Absorption issues: Buyer beware
Curcumin in its "raw" state is very poorly absorbed.
As researchers put it a few years back, “The potential health benefits of curcumin are limited by its poor solubility, low absorption from the gut, rapid metabolism and rapid systemic elimination.”
Until the past several years, most clinical trials employed raw curcumin, so we're just beginning to realize the pigment's true health potential.
Fortunately, the absorption problem has been overcome using several different approaches, but most methods of enhancing absorption make curcumin very costly.
The simplest — and most cost-effective way by far — to enhance absorption is to combine curcumin with turmeric’s own “volatile” compounds, which appear to provide their own health benefits.
When you compare the cost-benefit ratios of various “enhanced” curcumin supplements, the one that combines curcumin with turmeric’s volatile oils — called BCM-95 — comes out on top.
In addition, curcumin is better-absorbed when it's consumed along with fats, either from foods, or from supplements such as fish oil, which delivers broadly beneficial omega-3s.
That’s why, for optimal absorption, it’s wise to take curcumin supplements with a meal that provides significant amounts of fat.
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