Turmeric, a vibrant yellow spice commonly used in Indian cuisine, has gained popularity worldwide for its potential health benefits. The key compound responsible for these benefits is curcumin in general as well as for joint pain, which has been the subject of numerous studies.
Curcumin itself has been shown to have anti-inflammatory properties. Inflammation is a natural response by the body to protect against injury or infection. However, chronic inflammation can contribute to the development of various diseases, including arthritis. Studies have indicated that curcumin may help reduce inflammation and alleviate symptoms of osteoarthritis and rheumatoid arthritis as well as joint pain and swelling in general.
Short Answer: There is a lot of evidence to suggest that curcumin is a good additional option for people looking to reduce arthritis pain. It is one of the most well studied and well backed natural remedies. It has been shown to have notable anti inflamatory and pain relieving effects. What's more is that it's mechanisms for action are quite well understood. The only real issue with curcumin is that it can be rough on the stomach for some individuals and the optimal dose is not well established although a minimum of 500mg daily seems to be required. Curcumin should not be mixed up with plain turmeric as it only makes up around 3-8% of turmeric  depending on where the plant was grown, soil conditions etc.
How Does Turmeric Work For Arthrtitis and Joint Pain?
The active components of turmeric are mainly curcumin and its derivatives, including demethoxycurcumin and bis-demethoxycurcumin These compounds have been shown to modulate various inflammatory pathways and transcription factors involved in energy metabolism.
Unlike ginger, another member of the Zingiberaceae family, turmeric and curcumin do not modulate COX-1 activity but instead modify NF-κB signaling  and proinflammatory cytokine production. To put this simply, the ingredients in turmeric reduce inflammation by blocking the bodies communication chanels that tell it to "inflame" itself. This makes it a particularly useful option to have along side other pain reducing options.
And ultimately why a lot of natural remedies add curcumin alongside ginger which effect COX-1 . As both have shown beneficial effects for joint health in slightly different ways and ginger acts more similarly to traditional pain relief. For example pharmacutical options for treating arthritis selectively target COX-2  which is more specific to inflamed tissue than COX-1. However, their long-term use is limited due to inadequate pain relief, immune disturbances, and serious adverse events. As a result, individuals are seeking alternative treatments with anti-inflammatory properties and minimal side effects. And COX-1 targetting as you'd find in ginger has been shown to relieve pain combined with curcumin there's a good amount of evidence to support their use as an alternative remedy.
The Evidence: Comparing Curcumin to Placebo
Several randomized controlled trials (RCTs) have examined the effects of curcumin on pain and physical function in individuals with osteoarthtis. A meta-analysis by Daily et al. (2018)  evaluated eight RCTs and found that curcumin supplementation resulted in a significant improvement in pain compared to placebo. The studies used various outcome measures, including the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and pain visual analogue scores (PVAS), to assess pain severity. Overall, curcumin consistently demonstrated a greater reduction in pain scores compared to placebo.
One study included in the meta-analysis, conducted by Nakagawa et al. (2014),  examined the effects of curcumin supplementation on pain in 50 KOA patients. The curcumin group experienced a greater reduction in pain scores compared to the placebo group, and fewer curcumin-treated patients required additional analgesic medication. These findings suggest that curcumin has the potential to effectively alleviate pain in individuals with KOA.
Curcumin vs. Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)
In addition to comparing curcumin to placebo, some studies have also investigated the therapeutic response of curcumin compared to NSAIDs, which are commonly used to manage pain and inflammation in knee osteoarthritis. A detailed meta-analysis directly compared curcumin to NSAIDs and found no significant differences in outcome scores between the two treatments. ] This suggests that curcumin may be as effective as NSAIDs in relieving pain and improving physical function in individuals with osteoarthritis.
An example of one of the studies published in BMC investigated the effects of curcumin on knee osteoarthritis symptoms. The researchers enrolled 139 individuals with moderately severe knee osteoarthritis who required treatment with an NSAID. The participants were randomly assigned to receive either diclofenac, a commonly prescribed NSAID, or curcumin for one month. 
The results of the study showed that both diclofenac and curcumin significantly relieved arthritis symptoms and improved knee function. Approximately 94% of those taking curcumin and 97% of those taking diclofenac reported at least a 50% improvement in their symptoms. Interestingly, individuals taking curcumin reported fewer side effects compared to those taking diclofenac. None of the curcumin users required treatment for stomach-related issues, whereas 28% of the diclofenac group needed stomach-related interventions.
Another noteworthy finding from the study was that individuals taking curcumin experienced an average weight loss of nearly 2% within four weeks. This observation suggests a potential additional benefit of curcumin for individuals who are looking to manage their weight alongside osteoarthritis symptoms.
Meta Analysis of Curcumin for Arthritis
Several meta-analysis have shown several key findings regarding the efficacy of curcumin for arthritis symptoms. Mutiple randomly controlled trails reported a significant reduction in PVAS with turmeric/curcumin compared to placebo. The meta-analysis of four studies also showed a decrease in WOMAC scores (the five items of pain used for subjective measurements) with turmeric/curcumin treatment. Furthermore, there was no significant difference in PVAS between turmeric/curcumin and pain medication in the meta-analysis of five studies. 
Safety and Side Effects of Curcumin
One important aspect of any therapeutic intervention is its safety profile. The studies included in the meta-analysis reported no significant adverse events associated with curcumin supplementation. This suggests that curcumin is well-tolerated and has a low risk of side effects. However, it is worth noting that high doses of curcumin have been associated with mild gastrointestinal symptoms such as nausea or diarrhea. Nonetheless, the overall safety profile of curcumin appears to be favorable.
Based on the available evidence, curcumin and turmeric preparations appear to be safe at doses not exceeding 1200 mg/day for up to 4 months. However, it is essential to note that high doses of curcumin may alter iron metabolism, potentially causing iron deficiency in susceptible individuals.
Optimal Dosing, Frequency, and Formulation of Curcumin for Arthritis
While the evidence suggests that curcumin may be beneficial for joint health, there are still uncertainties regarding optimal dosing, frequency, and formulation. It seems a minimum of 500mg a day is required, but due to the varying doses used in curcumin for arthritis studies there is currently no "optimal" dose.
Curcumin as an Additional Treatment
Curcumin should be considered as an adjunctive therapy for osteoarthritis, in addition to traditional treatments. The evidence suggests that it can improve pain without significant adverse effects. However, it is important to note that curcumin is not a replacement for more established therapies, and further research is needed to definitively recommend its use in osteoarthritis management. While the study on curcumin for osteoarthritis has given very promising results, it is not sufficient to make curcumin a standard treatment for osteoarthritis at this time. More research is needed to fully understand the potential benefits, optimal dosages, long-term efficacy, and safety profile of curcumin. Individuals with osteoarthritis should consult with their healthcare providers before incorporating curcumin or any other dietary supplement into their treatment regimen.
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