Arthritis and nutrition

Arthritis is a common condition that causes pain and inflammation in the body’s joints. In the UK, more than 10 million people have arthritis, or other similar conditions that affect the joints.

Although arthritis is more common in older people, it can affect people of all ages, including children. Arthritis can affect quality of life and make daily activities a challenge.

It is important to have a balanced diet and maintain a healthy body weight when you live with arthritis. A healthy lifestyle can help to manage the symptoms and help to reduce the risk of other diseases, such as obesity, cardiovascular disease and type 2 diabetes.

There is no special diet or ‘miracle food’ that can cure arthritis, but there is a great deal of interest in how diet may affect people living with arthritis. It is important to note that much of the current popular advice does not have robust scientific evidence to support it and research is still developing. We understand this may be confusing, so we have summarised the key information below.  

What are the most common types of arthritis?

Two of the most common types of arthritis are osteoarthritis (OA) and rheumatoid arthritis (RA). 

Osteoarthritis

Osteoarthritis (OA) is the most common type of arthritis in the UK, affecting nearly 9 million people. It is a disease that damages the cartilage (the tissue that cushions joints and helps them move smoothly) making movement harder and leading to increased stiffness and pain.

Osteoarthritis can affect any joint in the body, but the most common areas affected are the knees, hips and small joints in the hands.

The management of OA focuses on symptom management. It is not possible for specific foods or nutritional supplements to cure osteoarthritis, but having a healthy, balanced diet and exercising can be important to help ease symptoms. It is widely accepted that weight reduction (if overweight) in combination with increased physical activity can improve function and symptoms such as pain and stiffness.

Osteoarthritis and diet  

Reaching or maintaining a healthy weight can relieve pain, improve function, and slow the progression of OA.

Being overweight or obese are crucial factors in OA since overload to the affected joint is one of the risk factors for developing OA or worsening of symptoms. Losing weight reduces pressure on joints, particularly weight bearing joints like the hips and knees.

There is increasing interest in not only reducing weight but specifically in reducing fat tissue, as fat tissue in our bodies is ‘active’ and can secrete several chemical factors, some of which may have inflammatory effects.

If you’d like more information on weight loss talk to your GP or practice nurse. You can also find tips and advice on our healthy weight loss page.

Osteoarthritis and physical activity

Painful joints and stiffness can make it more difficult to be physically active. However, physical activity can help maintain a healthy body weight and protect joints by keeping muscles strong, reduce the load on our joints, increase your range of movement and reduce stiffness.

Muscle strengthening exercises (activities such as yoga, pilates or dancing that work the major muscles) and aerobic exercise (activities such as walking, cycling or swimming that temporarily increase your heart rate and respiration) are recommended.

It is important to find the right type of activity for you. If you are unsure, ask your GP to refer you to a physiotherapist, who can help you work out a suitable programme.

Healthy dietary patterns for osteoarthritis and more 

Some research suggests a link between high blood cholesterol and an increased risk and progression of OA. Although it is unclear whether lowering blood cholesterol will improve OA, raised blood cholesterol is a risk factor for cardiovascular disease. 

It is therefore important to have a balanced, healthy diet as it may help to reduce blood cholesterol and the risk of cardiovascular disease. It will also help you to maintain a healthy weight.

Rheumatoid arthritis (RA) is a long-term inflammatory condition that causes pain, swelling and stiffness in joints. The hands, wrists and feet are typically affected, but it may affect any joint. 

RA is an auto-immune condition that happens when the body’s immune system, which usually fights infection, starts to attack healthy joints instead. At times symptoms can become suddenly worse causing severe pain and making it hard to go about everyday life. 

RA is associated with a number of complications and comorbidities (conditions that often occur together with another condition) such as an increased risk of cardiovascular disease and osteoporosis (a condition that weakens bones).

Rheumatoid arthritis is less common than osteoarthritis, but it nonetheless is estimated to affect over 400,000 adults in the UK. There is no permanent cure, and it can have a significant personal impact for people with the disease and their families. However, early treatment can help to control it and help people carry on active and full lives. Medical management with drug therapy aims to relieve pain and stiffness whilst helping mobility. 

Rheumatoid arthritis and diet 

Diet and inflammation

People living with RA often use dietary changes to try to improve symptoms. A wide range of dietary advice exists but there is a lack of scientific information in support of the claimed benefits.

The most common dietary patterns people with RA try are those that may have anti-inflammatory benefits or increase antioxidant levels (see section on antioxidants below). Other dietary strategies focus on cutting out foods or food groups that may be perceived as the cause of symptoms. However, much clarification is still needed to understand the relationship between diet and RA. Available evidence does not establish diet as a substitute for pharmaceutical treatments.

For people living with RA it is important to be aware of the dietary advice for which there is some evidence of benefit, and where the evidence is limited, as well as awareness that some alternative diets proposed can compromise nutrient intake.

Eliminating foods

It is a common belief among people living with RA that certain foods or ingredients have adverse effects, and that a food allergy/intolerance may cause or make inflammation worse.

Several reviews have aimed to evaluate the effectiveness of a range of interventions that restrict certain foods for the treatment of RA and management of its side effects. These include:

•   Vegan diets
•   Elemental diets (liquid diets that contain nutrients that are broken down to make digestion easier)
•   Fasting
•   Elimination diets (used to find foods that might be the cause of symptoms)

However, there is very limited research in this area and the results remain largely unclear. It is uncertain whether any of these dietary strategies can improve pain, stiffness, and mobility. Certain individuals or subgroups may show improvement if they cut out certain foods, but many others do not. Furthermore, some of these diets may be difficult to stick to, and people may lose weight even though they did not need or plan to.

There is no test that can identify if someone with RA may benefit by a change in diet, although offending foods can be identified through an exclusion programme under the supervision of a dietitian.

Several tests that claim to identify food allergies can be bought on the high street or online but are not recommended because there is little evidence that they work.

These include:

•   Applied kinesiology (a process based on muscle testing)
•   Vega test (which involves measuring electromagnetic conductivity in the body)
•   Hair analysis

Fasting

Fasting has been reported to reduce pain and inflammation in some people with RA. It is recognised that inflammatory activity is reduced when fasting, but the effects are short term and could also be a result of weight loss. Symptoms return when regular diets resume and fasting carries health risks, so it is not recommended.

Authoritative bodies typically will not suggest cutting out important food groups as this can increase risk of nutritional deficiency.

Milk and dairy foods

There has been some suggestion that dairy foods are associated with inflammation, but the evidence is conflicting, and limited due to small trials.

Studies of milk and dairy products more typically suggest a neutral or even beneficial effect on levels of inflammatory markers and would not point to an adverse inflammatory effect.

Specific dietary guidelines are difficult to define in people living with RA as there are individual differences. However, as dairy products can play an important part of a healthy, balanced diet, based on the available data, there is no evidence to support exclusion of dairy products unless an intolerance or allergy are shown. If you think you may have an adverse reaction to milk and dairy products talk to your GP or a health professional involved in your care such as your specialist nurse.

The nightshade plant family

Aubergines, peppers, tomatoes, potatoes and goji berries are all members of the nightshade family. Some people believe that solanine, one of the alkaloids (naturally produced compounds in various plants), contributes to inflammation and pain in arthritis. However, the connection between arthritis and nightshades is largely considered anecdotal. There is a lack of any clinical human studies and so currently there is no scientific evidence that nightshade vegetables make arthritis symptoms worse. It is also worth noting that solanine is also found in blueberries, apples, cherries, okra and artichokes, none of which is in the nightshade family and not included in anecdotal reports of adverse effects.

The fruit and vegetables that contain solanine are rich in nutrients and antioxidants. However, if you think you may have an adverse reaction to vegetables like potatoes, tomatoes and peppers then talk to your GP or a health professional.

Supplements for the side effects of medication

Your specialist team or GP may prescribe certain nutrition supplements because they can be useful in preventing the side effects of medications. 

Folic acid

Folic acid supplements may help prevent some of the side effects of methotrexate, a conventional disease modifying anti-rheumatic drug (cDMARD), commonly used in first line management of RA. Folic acid reduces toxic effects and improves continuation of therapy and compliance.

The British Society for Rheumatology guidelines recommends a typical folic acid dose of 5mg once weekly, not on the same day as methotrexate (also typically taken once weekly).

Calcium and vitamin D

Calcium and vitamin D are essential nutrients for bone health and supplements may be prescribed for patients with RA taking steroids, which can increase the risk of bone loss and osteoporosis.

Steroids may be offered as a short-term treatment to manage flares in people with recent onset (or established disease) to rapidly decrease inflammation, and to improve symptoms while waiting for a new cDMARD to take effect (which can take 2–3 months).

Although laboratory research has suggested that vitamin D may have anti-inflammatory effects, further studies are needed to better understand the role of vitamin D in inflammatory conditions, and currently there is no evidence that vitamin D supplements are of benefit in RA. Regardless of possible effects on inflammation, it is recommended that all adults take a daily supplement containing 10µg (micrograms) of vitamin D during the autumn and winter months, when the sun is not strong enough for the body to make vitamin D.