Curcumin is a natural active ingredient found in turmeric.
It has long been used in Asian countries as a medicinal herb. It is widely studied for its anti-inflammatory, anti-mutagenic, anti-microbial, and anti-cancer properties.
FDA has approved curcumin as GRAS (generally recognized as safe).
Key Benefits of Curcumin / Turmeric Supplements
The key benefits of curcumin supplements include improving and management of inflammatory, chronic conditions including arthritis, diabetes, Alzheimer’s disease, depression, irritable bowel syndrome, and pathological pain. Most of its effects are due to its anti-inflammatory and anti-oxidant properties.
Several studies have found that curcumin inhibited different inflammatory mediators, including cyclooxygenase 2, lipooxygenase, nitric oxide, NF-kB, and interleukin-12. It can modulate several transcription factors and alter signaling pathways. It can also inhibit tumor proliferation and induce apoptosis of cancer cells. 
1. Curcumin supplements reduce the symptoms of osteoarthritis
Curcumin supplements reduce the symptoms of osteoarthritis. Osteoporosis is a degenerative disease characterized by knee pain and joint stiffness.
Curcumin has a potential role in decreasing the release of inflammatory mediators, reducing the over-production of reactive species, and thereby it can prevent the progression of osteoarthritis.
In a controlled clinical trial involving 100 patients with spinal cord injuries, the curcumin supplemented group had a significant increase in bone mineral density.
In a three months study with 50 osteoporosis patients, Meriva (curcumin-phosphatidylcholine complex) reduced the joint pain and decreased the WOMAC score by 58%. 
In an osteoporotic mouse model, oral curcumin(50mg) supplementation reduced the progression of osteoarthritis.
What it means: The clinical trials reported that curcumin supplementation reduces knee pain and increases bone mineral density suggesting its potential role in the treatment of osteoporosis. Future studies will determine the role of curcumin in the treatment of arthritis.
2. Curcumin supplements may suppress the proliferation and metastasis of cancer cells.
Extensive research suggests that curcumin has a role in suppressing tumor proliferation by downregulating several transcription factors and inhibiting proinflammatory cytokines.
It may reduce angiogenesis and induce apoptosis in cancer cells. 
In an in vivo study, curcumin(10-25uM) inhibited bladder cancer cell growth and induced the apoptosis of cancer cells.
A similar anti-cancer effect of curcumin was found in the prostate cancer animal model.
The microarray analysis revealed that curcumin inhibited inflammatory cytokines, which in turn prevented the metastasis of breast cancer cells.
In another study involving breast cancer patients, oral curcumin supplementation (6 g) during radiotherapy reduced the severity of radiation dermatitis.
Some pancreatic cancer patients who received 8 g of curcumin orally showed some biological activity.
What it means: Several in vitro and in vivo studies reported that curcumin inhibits inflammatory cytokines, down-regulates transcription factors, and induces apoptosis, thereby may suppress proliferation and metastasis of cancer. It reduced the severity of radiation dermatitis in breast cancer patients. However, extensive in-human studies are required to determine the beneficial effect of curcumin to treat or prevent cancer in humans.
3. Curcumin supplements may reduce insulin resistance and delay the development of type II diabetes
Some studies have shown that curcumin supplements may delay type II diabetes and decrease insulin resistance.
Obesity-induced inflammation leads to insulin resistance and type II diabetes.
Curcumin extract may reverse the obesity-induced inflammation.
In a randomized controlled study with 240 subjects who are prediabetic, nine months of curcumin supplementation reduced the chance of prediabetic individuals developing type II diabetes.
In an insulin-resistant mouse model, curcumin supplementation reversed the inflammatory reactions and improved insulin resistance. 
What it means: A study revealed that curcumin may reduce the likelihood of developing type II diabetes in a prediabetic population. It can, therefore, be used as a potential therapy for prediabetic individuals. Mouse models reported that it may reduce insulin resistance by suppressing the obesity-induced inflammatory responses. More research with human trials is required.
4. Curcumin supplements may treat psoriasis
Recent studies have proposed that curcumin may treat psoriasis. Psoriasis is a chronic inflammatory disease of the skin. Curcumin supplements may suppress inflammatory cytokines of skin.
In a mouse model, curcumin inhibited potassium channels expressed on T cells, which plays a key role in the onset of psoriasis.
In an in vitro model for psoriasis, curcumin at 25uM and 50uM inhibited the proliferation of psoriatic cells by down-regulating the proinflammatory cytokines.
What it means: Some studies suggest that curcumin may inhibit potassium channels and down-regulate the proinflammatory cytokines associated with psoriasis. The studies suggest that curcumin may be a potential candidate to treat psoriasis. Large placebo-controlled trials are required to determine the therapeutic effect of curcumin for psoriasis.
5. Curcumin supplements may reduce depressive symptoms
Several studies have suggested that curcumin may treat depressive symptoms.
Curcumin exerts its anti-depressive effect by lowering neuroinflammation, protecting against oxidative damage, and modulating neurotransmission.
In a randomized, placebo-controlled study with 123 individuals with major depressive disorder, curcumin supplements were more significant in reducing depression symptoms.  
In another placebo-controlled study involving 56 individuals, curcumin supplementation (500 mg twice a day) significantly improved mood-related symptoms 4-8 weeks after treatment.
In another study, 117 subjects with major depressive disorders were assigned to receive curcuminoids and piperine alongside anti-depressive therapy for six weeks. The curcuminoids group had a reduction in anxiety and depression.
What it means: The studies show that curcumin supplements alone or in combination with piperine may reduce the depressive symptoms in patients with major depressive disorder. However, further studies with larger sample sizes are necessary to elucidate the efficacy of different doses of curcumin in treating depression.
6. Curcumin supplements may help in the management of pathological pain
Preclinical and clinical studies suggest that curcumin supplements may help in the management of pathological pain due to nerve injury, diabetic neuropathy, chemotherapy-induced neuroinflammation, and alcoholic neuropathy.
In a study, repeated curcumin administration downregulated the production of IL-1β and reduced neuropathic pain in mice model.
In a placebo-controlled study, 50 patients who had laparoscopic cholecystectomy were supplemented with curcumin following the operation. The patients had significantly lower pain scores.
2g of Mireva ® (curcumin formulation) had acute pain-relieving properties comparable to acetaminophen.
What it means: Apart from arthritic pain, several studies show that curcumin supplementation may help in managing post-operative pain, neuropathic pain, and nerve injury pain. The mechanisms of the pain-reducing effects of curcumin are not very clear. Therefore more clinical trials are required to elucidate the effectiveness of curcumin in treating patients suffering from pain.
7. Curcumin supplements may break amyloid beta-plaques of Alzheimer’s disease
Several studies are investigating the potential role of curcumin in breaking amyloid plaques. Alzheimer’s disease is a neurodegenerative disease characterized by amyloid plaques.
Curcumin may help the immune system to clear the amyloid plaques and prevents the neural inflammation.
In vivo mouse studies showed that curcumin injected binds beta-amyloid plaques and prevents amyloid aggregation.
In a transgenic mouse model, low-dose curcumin treatment reduced amyloid burden by 43-50%, thereby showing a promise of curcumin in the prevention of Alzheimer’s disease.
What it means: The studies suggest that curcumin may break amyloid plaques, a characteristic of Alzheimer’s disease. It is yet to demonstrate such effects in humans. Therefore, clinical trials are required to determine the therapeutic effect of curcumin and its role in treating Alzheimer’s disease.
8. Curcumin supplements may reduce anxiety symptoms
Epidemiological studies have found that curcumin may reduce anxiety symptoms via its anti-inflammatory properties.
In a rodent model, in vivo supplementation of curcumin increased DHA, which is essential for brain development. Increased DHA improved anxiety-like behavior.
In a study, rats received curcumin (20,50 or 100 mg/kg) for 14 days and then exposed to single prolonged stress.
Curcumin improved neurochemical abnormalities and reversed serotonin dysfunction.
In a double-blind, randomized study, 30 obese subjects received 1g of curcumin for 30 days. Curcumin supplemented group had significantly reduced the Beck Anxiety Inventory (BAI) scores.
What it means: The animal studies showed that curcumin may improve symptoms of anxiety by reducing inflammatory mediators. In a clinical trial, it reduced anxiety symptoms in obese individuals. Human clinical trials are required to determine the anxiolytic-like effects of curcumin in treating psychiatric disorders.
9. Curcumin supplements may reduce lipid profile components
Some studies have suggested that curcumin supplementation may lower triglycerides and LDL cholesterol levels.
High triglycerides and LDL cholesterol levels increase the risk of cardiovascular disease.
In a randomized study with 33 patients with coronary artery disease, lipid profile components were reduced significantly in curcumin supplemented (500 mg four times a day) group compared to placebo.
In a placebo-controlled trial, 33 metabolic syndrome patients taking curcumin extract (630 mg thrice daily) had significantly lower LDL levels.
However, in a meta-analysis involving randomized clinical trials, curcumin supplementation did not have any effect on lipid profile components within a heterogeneous population.
What it means: Some studies reported that curcumin supplementation may reduce serum LDL, triglycerides, and VLDL cholesterol levels in patients with coronary artery disease and metabolic syndrome. Some research did not support the lipid modulating properties of curcumin, and therefore more detailed work with different curcumin supplementation duration is required.
10. Curcumin supplements may improve the symptoms of irritable bowel syndrome (IBS)
Some studies have shown that curcumin may modulate gut microbiota and improve symptoms of IBS through its anti-inflammatory and anti-oxidant properties.
IBS is the digestive system disorder causing stomach cramps, diarrhea, and constipation. 
In a study, curcumin administration decreased the length of the small intestine and intestinal motility in the rat model.
In an IBS rat model, curcumin regulated neurotransmitters, BDNF and CREB signaling pathways in the intestinal system associated with IBS.
In a pilot study, about two-thirds of subjects reported less abdominal pain and discomfort when supplemented with turmeric extract for eight weeks. 
What it means: Some studies reported that curcumin supplements reduced symptoms of IBS including, abdominal pain and discomfort. More human studies are required to determine the benefit of curcumin.
11. Curcumin supplements may reduce exercise-induced oxidative stress and inflammation
Curcumin may reduce exercise-induced inflammation and offset exercise-induced muscle damage.
High-intensity exercise increases the release of inflammatory mediators and produces delay onset muscle soreness and causes muscle damage.
In a randomized controlled trial involving 19 male, curcumin supplementation reduced the muscle damage and soreness following the exercise.
In a study, 63 physically active men and women were supplemented with CurcuWIN® and followed a downhill running protocol. 200 mg supplemented group showed an improvement in soreness.
What it means: Some studies showed that curcumin may reduce exercise-induced inflammation and muscle soreness in physically active individuals. It could facilitate a faster recovery time. However, more studies are required to determine the potential benefits and mechanisms of curcumin in the exercise-induced inflammation process.
Possible Side effects of Curcumin
Curcumin is generally safe when taken orally or applied to the skin. Sometimes, it can cause mild side effects including, stomach upset, acid reflux, dizziness, and diarrhea at higher doses
Safety Tips while taking Curcumin
Curcumin is likely to be unsafe during pregnancy when in medicinal doses as they suppress iron absorption.
Avoid curcumin when the individual has gallbladder problems, diabetes, gastroesophageal reflux disease, and hormone-sensitive conditions like breast cancer, endometriosis.
Consult a practitioner before using curcumin.
Possible Drug Interactions Interactions
Curcumin may interact with blood thinners and diabetes medications. It can increase the blood-thinning effects of blood thinners. It may interact with aspirin, ibuprofen, enoxaparin, heparin, and warfarin.
There is no recommended dietary intake for the curcumin. According to examine.com, 500mg of curcumin is used with 20mg of piperine thrice a day for research studies.
BCM-95® (Biocurcumax), a patented bio-enhanced preparation of the curcumin, is supplemented 500 mg twice a day. 200-500 mg of Meriva® (a patented lecithin formulation of curcumin) is taken twice a day.
Curcumin is gaining worldwide attention for its several health benefits.
Research suggests that it may help in the management of chronic conditions including, arthritis, hyperlipidemia, IBS, depression, anxiety, and psoriasis. It may have a role in preventing the proliferation and metastasis of cancer.
Curcumin, when combined with piperine, had improved bioavailability.
Future in-human trials with large sample size and better curcumin complex will help to determine the effectiveness of its claimed benefits.