Arthritis symptoms include joint pain and inflammation.
Patients could reduce signs of the condition by making dietary changes, according to Arthritis Research UK.
As well as a healthy and balanced diet, some food supplements could help to ease joint pain, it claimed.
Omega-3 fatty acid supplements could help with inflammatory arthritis symptoms, it said.
“Omega-3 polyunsaturated fatty acids EPA and DHA [found naturally in oily fish] can be helpful if you have inflammatory arthritis,” said Arthritis Research UK.
“Or try eating oily fish instead – at least twice a week, but not more than four times a week.
“If you’re vegetarian, or fish oil disagrees with you, you can get other types of omega-3 fatty acids from flaxseed oil, rapeseed oil and walnuts.
“If you want to increase your intake of omega-3 fatty acids, we recommend taking pure fish oil rather than fish liver oil.”
Quite large amounts of omega-3 are needed for the best effects, so 3g of EPA and DHA could be taken.
It will take about three months for patients to notice the benefit, Arthritis Research UK warned.
If the high doses of fish oils upset your stomach, try taking two or three smaller doses during the day, it recommended.
Other supplements that could benefit arthritis patients include vitamin E, selenium and vitamin D.
Arthritis symptoms can also include muscle wasting, restricted movement and warm, red skin over the affected joints.
There’s currently no cure for arthritis, but some treatments could help to slow down the condition, said the NHS.
Eating healthily could help to reduce arthritis symptoms.
Fruit and vegetables, starchy foods, meat, dairy and fish all form part of a balanced diet.