Chondroitin, also known as chondroitin sulfate, is an over-the-counter nutritional supplement consisting of sulfated glycosaminoglycans, a fundamental building block of the human cartilage molecule, and other compounds, such as glucosamine, that have been used in medicine for more than 40 years.
What are the benefits of using chondroitin in empirical medicine? Are there any side effects of chondroitin? See text analysis for details
What is Chondroitin?
Chondroitin (Chondroitin Sulfate) is the main component of the extracellular matrix of mammalian connective tissues, including cartilage, blood vessels, bone, skin, ligaments and tendons.
Chondroitin plays an important role in the high content of bone collagen, making cartilage stress-resistant and elastic under various loading conditions, and resistant to external stresses.
At the molecular, cellular, and organ levels, chondroitin provides specific biological functions such as cell adhesion, cell division and differentiation, morphogenesis, organogenesis, and neural network formation.
In addition, chondroitin has also been shown to have anti-inflammatory, anti-metabolic, anti-apoptotic, antioxidant, cell signaling pathway regulation and other effects.
What are the proven benefits of chondroitin?
1. Chondroitin is beneficial for osteoarthritis
Osteoarthrosis, the most common type of arthritis (especially large weight-bearing joints such as the knee and hip), is characterized by progressive degeneration of the cartilage matrix, subchondral osteosclerosis and osteophyte formation
Clinical symptoms include pain, stiffness, joint effusion, and joint deformity, while risk factors such as age, sex, previous joint injury, obesity, genetic predisposition, joint alignment and joint morphology have important implications for the etiology of osteoarthropathy.
A meta-analysis (18 randomized, placebo-controlled trials involving 3791 patients with osteoarthritis) found that overall, chondroitin significantly reduced pain and improved joint function (although results remain inconsistent). Note 1
In addition, limiting the analysis to studies at lower risk of bias found that pharmaceutical-grade chondroitin (IBSA source) had greater analgesia and functional improvement
Another meta-analysis (18 randomized, double-blind, placebo-controlled trials) showed that chondroitin had a small to moderate effect on reducing osteoarthritis-related pain, but had little effect on joint space stenosis and no effect on cartilage volume. Note 2
*Conclusion: Oral chondroitin may be a positive help for osteoarthritis, but more large trials are needed to support this
2. Chondroitin reduces the risk of colorectal cancer
Colorectal cancer is defined as cancer caused by the epithelium of the colon or rectum, where the intestine begins to bleed and become blocked as a result of the growth of the tumor.
Symptoms such as changes in bowel habits such as diarrhea, constipation lasting more than several days, rectal bleeding, weakness and fatigue, weight loss, cramps, or abdominal pain may occur.
As with other types of cancer, mutations in specific genes can lead to colorectal cancer, which can be divided into sporadic, hereditary, and familial depending on the origin of the mutation.
Two large prospective cohort studies showed that glucosamine in the absence of chondroitin was not associated with colorectal cancer risk, whereas glucosamine + chondroitin was significantly associated with risk (RR: 0.77). Note 3
This protective relationship did not change significantly depending on follow-up period, sex, aspirin use, body mass index, or physical activity.
*Conclusion: The use of glucosamine + chondroitin is associated with a lower risk of colorectal cancer and may have the potential for chemoprevention.
3. Chondroitin is beneficial for recurrent urinary tract infections
Urinary tract infections are common in women, the elderly, immunosuppressed patients, and catheters, and almost half of women experience a urinary tract infection at least once in their lifetime.
Various types of urinary tract infections include pyelonephritis (kidneys), cystitis (bladder), and urethritis (urethra).
Relapse is defined as having more than 6 infections within 2 months, or 12 infections within 3 months and being completely cured within at least two weeks.
A meta-analysis of four studies of recurrent bacterial cystitis in adult women showed that either intrabladder perfusion of mucopolysaccharide hyaluronic acid (HA) or mucopolysaccharide hyaluronic acid plus chondroitin sulfate (HA-CS) significantly reduced cystitis recurrence, mean time to UTI recurrence, pelvic pain, and total urgent/frequency score. Note 4
*Conclusion: For adult women with recurrent bacterial cystitis, the use of intravesical polysaccharide hyaluronic acid plus chondroitin sulfate is a positive help to improve the condition, but limited by the small sample size and risk of bias, more studies are still needed to support it
4. Chondroitin is beneficial for interstitial cystitis
Interstitial cystitis/bladder pain syndrome is a chronic bladder disorder characterized by bladder pain, frequent urination, nocturia, or peeling or thinning of the urinary tract (excluding urinary tract infection or other obvious pathological factors).
In the US census, the ratio of men to women is 1:9, and most urologists believe that the cause of interstitial cystitis/bladder pain syndrome may be related to urothelial dysfunction, chronic inflammation, impaired bladder circulation, hyperneurogenic, and systemic dysfunction.
A systematic literature review and meta-analysis (10 studies, 390 patients with interstitial cystitis) suggested that intravesical polysaccharide hyaluronic acid (HA) or mucopolysaccharide hyaluronic acid plus chondroitin sulfate (HA-CS) perfusion improved pain symptoms, quality of life, and other outcomes (e.g., bladder volume and voided output). Note 5
*Conclusion: For patients with interstitial cystitis, intrabladder mucopolysaccharide hyaluronic acid plus chondroitin sulfate perfusion can bring positive help to improve the condition, but limited by the small sample size and short follow-up time, more studies are still needed to support it
Are there any side effects of chondroitin?
Oral chondroitin is considered safe for most people in good health (most commonly studied for 6 years), but possible side effects or adverse effects include: bloating, nausea, diarrhoea, constipation, stomach pain, headache, swollen eyelids, swollen legs, hair loss, rash, arrhythmia
Safety precautions (7 contraindications to use)
1. Do not use by pregnant and lactating women (due to unknown safety)
2. Do not use for asthma/asthma patients, it may cause worsening of symptoms
3. Do not use for patients with abnormal coagulation function, it may increase the risk of bleeding
4. Early studies have found that the higher the concentration of chondroitin sulfate in the tissues surrounding prostate cancer, the higher the rate of cancer recurrence and spread (Note 6), but this phenomenon has not been found with chondroitin sulfate supplementation (Note 7).
5. Do not use in patients taking anticoagulants (such as Warfarin), which may affect the effectiveness of the drug and increase the risk of bruising and bleeding
6. May induce allergic reactions, if you have difficulty breathing, swelling of the face, lips, tongue or throat, rash and other discomfort after consumption, please seek medical assistance immediately
7. Patients with chronic liver disease should use with caution (or consult a doctor before use), there have been cases of drug-induced liver injury taking chondroitin in patients with mild and undiagnosed autoimmune hepatitis. Note 1