Dietary strategies for osteoarthritis

Did you know around 2.1 million Australians (1 in 11 people) suffer from osteoarthritis (1)? Osteoarthritis (OA) is the most common form of arthritis and is a leading cause of pain and disability worldwide, affecting an estimated 10% of men and 18% of women over 60 years of age (2). Its pathogenesis involves diverse risk factors such as age, biomechanical relationships, injuries and weight.

Earlier on, OA was thought to be a “wear and tear” degenerative joint disease, but it is now acknowledged that local and systemic inflammation play a key role in the disease progression and the emergence of pain.

Learn more about this topic in the HealthCert Professional Diploma program in Medical Nutrition Management – online nutrition training for GPs.

Current OA treatment is limited and largely confined to symptom management (3) through exercise programs or weight reduction (4), but a growing body of research suggests the role of anti-inflammatory foods and nutrients to reduce symptoms and slow OA progression (5-7).

The anti-inflammatory capacity of specific foods and nutrients is measured by something called the Dietary Inflammatory Index (8). Some foods that rank highly by this metric include:

• Green and other teas
• Beta-carotene, a Vitamin A precursor
• Magnesium-rich foods such as leafy greens, nuts and seeds, and wholegrains
• Flavanol-rich foods such as cocoa, kale, broccoli, and dark chocolate

In addition to the above, emerging research also suggests that certain supplements and dietary practices could benefit OA.

Omega-3 fatty acids

There is some evidence to suggest that high intake of omega-3s can help reduce inflammatory processes underlying OA symptoms (9), mostly from studies of fish oil supplements. As a rich source of omega 3 fatty acids, fish oil supplements have shown promise in reducing inflammation, alleviating joint pain, and improving overall joint health (10). From the food side, omega-3s can also be found in extra virgin olive oil, fatty fish such as salmon and sardines, nuts and seeds.

Limiting refined carbohydrates

Refined grains have been linked to higher levels of inflammatory markers in the blood, (11, 12) with the inverse being found for fibre-rich wholegrains (13). The amount of carbohydrates have also been shown to affect OA symptoms, with a study of patients aged 65-75 years of age demonstrating that a lower carbohydrate diet (compared to a low fat diet) led to a significant improvement in pain severity and quality of life in knee function (14). However, more research is needed. 

Curcumin

Turmeric is the golden child of the health food world, and it’s easy to understand why; turmeric’s most active component, curcumin, is a powerful anti-inflammatory and antioxidant that may help treat or prevent diseases ranging from OA to ulcerative colitis and cancer. Some studies demonstrate curcumin in improving pain scores and quality of life in patients with OA (15, 16). It’s important to note that benefits were demonstrated in high quality supplements – adding turmeric to lattes or curries won’t have the same effect!

Knowledge of key nutrition for osteoarthritis can help GPs provide meaningful and actionable dietary guidance to empower patients with osteoarthritis. Dietary additions which emphasise anti-inflammatory foods rich in omega-3s, fibre, and flavanols and which limit refined carbohydrates and sugar may be helpful for reducing pain severity and swelling and help improve quality of life.

Learn more with the online HealthCert Professional Diploma program in Medical Nutrition Management.

– Lynette Law, Accredited Practising Dietitian

Read another blog: Medical nutrition & nightshades: A look at the evidence

References