Ankylosing spondylitis (AS) is a form of arthritis that primarily affects the spine. There’s no dietary cure-all, but certain foods may help cut down bouts of inflammation.

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Generally speaking, if you have AS, eating a diet rich in vitamins and nutrients may help you manage your symptoms.

Keep reading to find out what foods are the most beneficial for AS and which may be best to avoid.

Per a 2020 literature review, some evidence suggests omega-3 supplements may reduce disease activity in people with AS. Besides supplements, many foods are also rich in this fatty acid.

Foods that contain omega-3 fatty acids include:

  • flaxseed
  • walnuts
  • soybean, canola, and flaxseed oils
  • cold-water fish, including salmon and tuna

Other foods contain smaller amounts, including Brussels sprouts, kale, spinach, and salad greens.

Learn more: What to eat to get more Omega-3.

Eating a variety of fruits and vegetables is a great way to get most of the vitamins and minerals your body needs to stay strong and healthy.

Fruits and vegetables are a healthful alternative to packaged snacks, typically high in calories with little or no nutritional value.

Including fresh produce in your everyday dietary plan doesn’t have to be difficult. For example, a hearty vegetable soup will warm you up on the coldest nights.

Or consider trying a berry-filled smoothie for a delicious and portable weekday breakfast. If the recipe you use calls for yogurt and you can’t eat dairy, you can substitute coconut or soy yogurt.

Learn more: The 14 most nutrient-dense vegetables and 20 healthy fruits that are super nutritious.

Whole foods and grains are high in fiber and may even decrease inflammation. However, even whole grains can trigger symptoms in some people with arthritis. This could be due to gluten, reports the Arthritis Foundation.

A 1-month elimination diet is one of the best ways to identify foods that trigger symptoms. Elimination diets remove certain foods thought to trigger symptoms and are added back into your diet one at a time while monitoring any changes in symptoms. It’s best to check with your healthcare professional before starting an elimination diet.

It’s important to keep a food diary during the elimination diet and when you reintroduce foods to determine if grains, specifically gluten, cause a flare-up. If not, add some health-promoting whole grain foods to your daily eating plan. These include:

  • whole oats
  • buckwheat
  • bulgur
  • millet
  • barley
  • spelt
  • quinoa
  • brown rice

Learn more: 14 healthy whole-grain foods (including gluten-free options).

If your diet is rich in fruits, vegetables, lean meats, nuts, legumes, and whole grains, you’re less likely to require dietary supplements. But if you’re lacking nutrients, you may benefit from an extra boost.

Types of dietary supplements include:

  • vitamins like vitamin D
  • minerals like iron or calcium
  • herbs and botanical compounds such as ginger and curcumin
  • amino acids such as tryptophan and glutamine
  • probiotics

Just be aware that some supplement manufacturers may make false claims. Talk with your doctor to learn which supplements, if any, might be useful for you.

Tell your doctor all the medications you’re taking, as some supplements may interfere with your prescriptions. Also, ask your doctor to recommend reputable supplement manufacturers.

Learn more: Dietary supplements: Benefits, side effects, risks, and outlook.

Some people with AS report improvement while on a low starch diet. More studies are needed, but some older research suggests that limiting starch may help decrease inflammation.

These food items contain starch:

  • breads
  • pastas
  • potatoes
  • rice
  • pastries
  • some prepackaged snack foods

A low starch dietary plan can include:

  • fruits
  • vegetables
  • meat
  • fish
  • milk and milk products
  • eggs

Note that while it might be tempting to think that eating low starch is the same as eating low carb, these are not necessarily the same dietary plans.

For some people, they can overlap. For example, if you stop eating foods like bread, pasta, or grains but you continue eating fruit and dairy, you could be eating low starch foods, but you’re not necessarily eating low carb options.

Sugar, sodium, and fat

Highly processed foods, and those that are high in sugar and fat, may cause inflammation. For some, dairy products can also cause inflammation.

Limiting foods that come in boxes, bags, and cans whenever possible and reading food labels can be helpful. Read Avoiding foods that contain too many extra ingredients that your body doesn’t need can also help manage your condition. Examples include foods that contain:

  • added sugars
  • high sodium content
  • saturated fats
  • trans fats (hydrogenated oils)
  • preservatives

Alcohol

Limiting your alcohol intake — or avoiding it altogether — if you drink is important. Alcohol can interfere or interact with medications, causing side effects.

Excessive amounts of alcohol can damage your liver, the lining of your small intestine, and your stomach. This can make it hard for your body to digest nutrients. It also can interfere with your ability to absorb and store certain vitamins.

NSAIDs

Many people with arthritis take nonsteroidal anti-inflammatory drugs (NSAIDs), which can damage your gut lining. Taking NSAIDs with bananas and active- or live-culture yogurt may help protect your gut.

Over-the-counter NSAIDs include:

  • aspirin
  • ibuprofen (Motrin, Advil)
  • naproxen (Aleve, Naprosyn)

Your doctor may also prescribe prescription-strength NSAIDs such as:

  • diclofenac (Zorvolex)
  • famotidine/ibuprofen (Duexis)
  • indomethacin (Tivorbex)
  • mefenamic acid (Ponstel)
  • meloxicam (Vivlodex, Mobic)
  • oxaprozin (Daypro)
  • piroxicam (Feldene)

Learn more: Everything to know about over-the-counter (OTC) anti-inflammatories.

Is caffeine bad for ankylosing spondylitis?

Fatigue can make AS symptoms worse. For this reason, it’s a good idea to avoid consuming things that can interfere with sleep too close to bedtime, such as coffee or alcohol.

How do I lose weight with ankylosing spondylitis?

AS can affect your weight. You might lose weight unintentionally because it can lower your appetite. On the other hand, since the symptoms can make it hard to stay physically active, you can also gain weight.

Research published in 2021 shows that being both underweight and overweight can worsen your symptoms. Maintaining a moderate weight is typically the most supportive approach. While it can be more challenging, staying physically active and eating a balanced diet are the best ways to maintain a moderate weight while living with this condition.

Is the Mediterranean diet good for ankylosing spondylitis?

A 2022 review of research shows people living with AS may do better by eating more vegetables and fruits, plant grains, and fish. These foods are all major components of the Mediterranean diet.

Sticking to a nutritious, well-balanced, and supportive eating plan can present challenges. But outlining steps that work well for you can be helpful.

Eating slowly, choosing smaller portions, drinking plenty of water, and limiting sugary foods are examples of things you can start doing today to support healthful eating patterns.

As always, avoid extreme or fad diets, as these can do more harm than good.

Talk with your doctor about your current eating plan, dietary needs, supplements, and all over-the-counter and prescription medications you’re taking.