This information is for anyone with axial spondyloarthritis, including people with ankylosing spondylitis
When you live with a long term condition it’s important to have a healthy diet
Maintaining a healthy weight
It is important you don’t become overweight as this increases the burden on weight-bearing joints and can increase pain.
When you are walking, the hips, knees and ankles bear three to five times your total body weight. So, for every pound you weigh, 3 to 5 pounds of extra weight is added to each knee when you walk. If you are overweight and lose 10 pounds in weight, 30 to 50 pounds of extra stress would be removed from the joints.
Healthy balanced diet
For a healthy balance diet consider eating:
- At least 4 portions of vegetables (including at least 1 leafy green vegetable) every day, along with 2 portions of fruit. As a child you might have been told to ‘eat your greens’, but it’s just as important to eat your reds, oranges, yellows, blues and purples, too. Scientists now know that many of the naturally occurring chemicals responsible for giving fruit and veg their bright colours actually help keep us healthy and free from disease. Fruit and vegetables contain hundreds of colourful phytochemicals that act as antioxidants, which help to ‘mop up’ potentially harmful molecules called free radicals before they get a chance to damage cells. All those different colours will add plenty of flavours and textures to dishes, making meals not just more healthy, but more enjoyable and satisfying
- Protein in the form of fish, beans, pulses, nuts, eggs and meat (not too much)
- Calcium for bone health. You need around 700mg a day – equivalent to 200ml semi-skimmed milk, a 150g pot of low-fat yogurt and a small matchbox sized piece of cheese
- Don’t forget starchy foods but try to choose wholegrain or wholemeal varieties, such as brown rice, wholewheat pasta and brown wholemeal bread. They contain more fibre and usually more vitamins and minerals than white varieties
- Omega-3 fatty acids have been shown to help some people with inflammatory arthritis. You can find these in oily fish (pilchards, sardines, mackerel and salmon, rapeseed oil, flaxseed oil and walnuts. Research suggests you need at least 2.7 g a day. Eating two portions of fish a week would only give you about 0.45 g per day, so you may want to take a supplement to reach the full amount. They act quite slowly so you’d need to give them at least a 3 month trial. Bear in mind high doses of omega-3 can give you mild stomach upsets. Don’t confuse fish body oil with fish liver oil (e.g. cod liver oil and halibut liver oil). It’s not safe to take fish liver oils in the large doses recommended for arthritis because of the risk of overdosing with vitamin A. This is particularly important for pregnant women, or women who might become pregnant, because vitamin A can harm the unborn baby.
What we know about diet and axial SpA
The question of the role of your diet on your axial SpA is important. In 2018 NASS funded a systematic review of all the research which has taken place into axial SpA and diet. The aims of this study were to investigate whether:
- People with axial SpA report different diets to the general population
- Diet is related to severity of disease
- People with particular diets are less likely to develop axial SpA
- Specific dietary interventions improve symptoms
The systematic review determined, from a relatively small number of studies, that the evidence on the relationship between diet and axial SpA is extremely limited and there were important methodological weaknesses in the studies reviewed.
The study concluded that:
Information on relationship between diet and axial SpA is extremely limited
Evidence on a possible relationship between axial SpA and diet is inconclusive
There is a need for large population-based epidemiological studies investigating the relationship between AS and diet
What we know about axial SpA and the gut
Researchers have been working over many years to understand the role of the gut bacteria in supporting your health, and how it may influence all sorts of diseases, including axial SpA.
Professor Julian Marchesi is a microbiologist who recorded a video with NASS to discuss the gut microbiome and the research he and others are carrying out into the microbiome.
Trying a change in diet
Trying to make sense of nutrition and your condition can sometimes be difficult. You may find it helpful to talk your dietary needs through with a nutritionist. You can ask your GP or Rheumatologist to refer you or you can consult a nutritionist privately. You can find a private nutritionist in your area at the Nutritionist Resource website.
Look at diet claims carefully
You should be suspicious of any diet that claims to treat or cure axial SpA. If such a diet existed, GPs and rheumatologists would know about it and would be recommending it to you. If you are tempted to try a diet, do discuss your plan with your GP or rheumatology team to help ensure that trying the diet will not cause you health problems.
Before trying any diet think whether it:
- Completely eliminates any food groups
- Allows only a few types of food
- Requires you to buy special products
- Has potentially harmful effects
- Provide scientific evidence to back its claims, rather than personal testimonies to support it