What is Turmeric?
Turmeric (Curcuma longa) is not ginger. While ginger belongs to the ginger family, turmeric is a member of the ginger family, and its rhizome is ground into a deep yellow powder, which is a primary ingredient in curry. Turmeric is widely used as a spice in many Middle Eastern and Asian countries, especially in India. Although ginger and turmeric may look similar, they are entirely different.
Turmeric, also known as Curcuma longa, is an underground rhizomatous plant. It has a slightly bitter and earthy taste. Its main component is curcumin, which has been known for its medicinal properties since ancient times, and it is used as an ingredient in traditional Chinese medicine. Generally, turmeric contains about 5% curcumin per 100 grams of turmeric powder.
Health Benefits of Turmeric, Especially for Joint Inflammation and Pain
In traditional medicine, turmeric is considered an herb due to its medicinal properties. It has been proven to have anti-inflammatory, antioxidant, antimicrobial, hepatoprotective, immunostimulatory, and anti-aging effects. Turmeric is increasingly accepted as a nutritional supplement and is used for its various health benefits. Curcumin, the main component of turmeric, has been found to have significant anti-inflammatory and antioxidant properties, which can significantly inhibit the growth and size of colon tumors in animal studies, making it a potential candidate for clinical research in cancer prevention. There are numerous studies that highlight the positive effects of turmeric on joint inflammation and pain in arthritis patients.
How Does Turmeric/Curcumin Help Improve Joint Pain?
The studies on the potential benefits of turmeric for the two common types of arthritis, osteoarthritis and rheumatoid arthritis, are extensive:
Research on Osteoarthritis (Degenerative Joint Disease)
Many studies indicate that daily intake of curcumin by osteoarthritis patients can effectively improve their related symptoms. A 12-week study showed that continuous curcumin intake significantly alleviated symptoms and improved walking speed in osteoarthritis patients. Similar studies have reported that daily curcumin intake increased the walking distance of osteoarthritis patients. Furthermore, animal studies found that curcumin regulates the inflammatory cytokines in chondrocytes, which can significantly slow down the development of osteoarthritis in mice.
Recent studies have also compared curcumin to nonsteroidal anti-inflammatory drugs (NSAIDs) in terms of efficacy. In a three-month prospective double-blind study, one group of arthritis patients was given diclofenac sodium (75 mg/day) plus a placebo, and the other group was given diclofenac sodium (75 mg/day) plus curcumin (1000 mg/day). Both groups showed significant improvements in arthritis symptoms. Although there was no statistically significant difference between the two groups, there was a trend towards better improvement in the group receiving curcumin. The group that received additional curcumin experienced greater improvements in pain levels and daily joint activity.
Other studies have found that direct use of curcumin for osteoarthritis treatment yields similar results to diclofenac sodium, but curcumin is better tolerated by knee osteoarthritis patients. Therefore, for patients who cannot use NSAIDs, curcumin can be a good alternative treatment option.
Research on Rheumatoid Arthritis
Another clinical study evaluated rheumatoid arthritis patients and divided them into three groups:
- Pure curcumin (500 mg/day)
- Pure diclofenac sodium (50 mg/day)
- Combined curcumin (500 mg/day) and diclofenac sodium (50 mg/day)
The study aimed to compare their:
- Disease Activity Score (DAS 28), a measure of disease activity in rheumatoid arthritis patients
- American College of Rheumatology (ACR) scores, a rating standard used to assess joint tenderness and swelling
The results showed that all three groups significantly improved their DAS 28 and ACR scores, with no statistical differences between the groups. However, the group taking pure curcumin showed the highest percentage of improvement. Furthermore, curcumin treatment was considered safe, with no adverse events. The group taking only curcumin showed a significant decrease in CRP (C-reactive protein), a marker for inflammation in rheumatoid arthritis patients, which suggests a reduction in inflammation. Additionally, curcumin has been found to suppress the production of pro-inflammatory Th17 cells and regulate T cells in rheumatoid arthritis patients, thereby inhibiting the autoimmune response.
Recommended Daily Intake and Precautions for Turmeric/Curcumin
There is currently no research indicating that turmeric poses any toxicity to the human body. The U.S. Food and Drug Administration (FDA) has listed turmeric in its GRAS (Generally Recognized As Safe) list, and there are no specific precautions associated with its use .
According to the World Health Organization (WHO), if curcumin, a compound found in turmeric, is used as a dietary supplement for daily nutritional purposes, it is recommended to intake 0 to 3 milligrams per kilogram of body weight, which is considered safe . The European Food Safety Authority (EFSA) also recommends an adequate daily intake (ADI) of 0 to 3 milligrams per kilogram of body weight for curcumin .
Research has explored daily curcumin intake in healthy adults at doses ranging from 500 to 12,000 milligrams to determine the maximum tolerable dose and safety. The results showed that even at a dose of 12 grams per day, curcumin did not exhibit significant harmful effects on the human body. However, very high doses may lead to side effects such as nausea and stomach discomfort  . Therefore, it is advisable to follow the WHO’s recommended intake.
How to Improve the Absorption of Turmeric/Curcumin?
Furthermore, the clinical efficacy of orally administered curcumin is not optimal due to its extremely low bioavailability and poor water solubility. These factors may limit its clinical effectiveness and applications. To address these limitations, various techniques have been developed to enhance the bioavailability of curcumin. These techniques include microemulsion technology (utilizing surfactants, co-surfactants, oils, and/or organic solvents to form microemulsions) and self-emulsifying drug delivery systems (SEDDS). Nano-particle water-soluble carrier systems have also been developed to improve water solubility and bioavailability, thus enhancing the efficacy of orally administered curcumin .
The use of nanosized water-soluble carrier systems has improved the water solubility of curcumin, thereby increasing its bioavailability, better absorption, and intra-body transport, leading to enhanced clinical efficacy  . The nanosized formulation of curcumin can be administered orally to increase its bioavailability, making it particularly useful in the production of dietary supplements .
A study lasting eight weeks, focusing on osteoarthritis, involved performing surgery on the meniscus of mice to simulate joint inflammation. One group received curcumin orally, while the other group applied nano-formulated curcumin directly to the wound. The study found that both groups had a significant impact on the regulation of inflammatory hormones in cartilage cells. While the orally administered curcumin group had a notable reduction in the progression of osteoarthritis, there was no significant effect on pain relief. Through behavioral observations, it was discovered that direct application of nano-formulated curcumin effectively alleviated pain associated with osteoarthritis. This was evident as the group showed reduced tactile sensitivity responses during daily activities, and changes in their mobility behavior .
Liquid self-emulsifying systems (SEDDS) can emulsify compounds by using a mixture of oil, surfactants, and co-surfactants. When it comes into contact with an aqueous medium (such as the fluids in the gastrointestinal tract), it spontaneously self-emulsifies, significantly enhancing absorption efficiency. This technology allows poorly water-soluble compounds to quickly self-emulsify in the gastrointestinal tract, thereby promoting compound dissolution and absorption, ultimately improving bioavailability  .
Many studies have now utilized SEDDS-designed formulations to improve the dissolution, release, and oral absorption rates of curcumin, thereby increasing its low bioavailability when taken orally . There are also numerous new self-nano emulsifying systems (SNEDDS) that have been designed through SEDDS modifications. These formulations have nanoparticle sizes and significantly enhance the bioavailability of curcumin, making them highly effective in improving its bioavailability  .