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  1. I was wondering if there was something that I could change in my daily diet to help keep the ankylosing spondylitis flare-ups from happening. Answer
  2. Thanks for you reply re: spondylitis and nutrition. Answer
  3. Does foods belonging to the nightshade family reduce stiffness in rheumatoid arthritis? Answer

I am a 36 year old white male who has been diagnosed with AS (ankylosing spondylitis). I was wondering if there was something that I could change in my daily diet to help keep the flare-ups from happening. I currently take anti-inflammatory meds when pain occurs, but would rather not if I could help it with a change of diet.

Unfortunately, at this time, there is nothing food related that causes flare-ups in ankylosing spondylitis. I periodically check research for my 2 family members who have AS. There has been some exploration of night shade vegetables and dairy products with no positive relief of symptoms.

I would recommend you follow a balanced eating plan using My Plate as a basis. It includes fruits, vegetables, grains, meat and beans, dairy with moderate fat and sweets.

Thanks for you reply re: spondylitis and nutrition. There are reams of studies, but few conclusions, as you may know and even fewer "cures". During years of talking with people about spondylitis and being the subject of two university hospitals on the topic, I think doctors know very little more than which anti-inflammatory medicines to suggest. Our weekly or other on-line chats reveal that individuals have such a range of diets which they believe help that there doesn't seem to be any cause-effect relationship. Many of us seem to avoid unhealthy foods in general, plus nightshades, excessive citrus, and so forth. But the few surveys which have been made also do not seem to reveal a significant pattern. Thanks for your interest.

You're welcome. It is very difficult for a person with inflammatory disease to separate fact from fiction or to relate foods eaten with pain since we eat meals with more than one food. Many people unwittingly eliminate healthy foods thinking specific foods are triggers for their arthritis.

New research suggests that the Klebsiella microbes found in the bacteria in the large bowel might be the trigger factor for ankylosing spondylitis. It has been suggested that reducing the amount of bowel bacteria which feed on starch for growth would reduce the amount of Klebsiella bacteria. A low starch eating plan would reduce the eating of bread, rice, pasta, potatoes, cakes, cookies and pie may decrease inflammation and symptoms, but the evidence isn't final yet.

I have rheumatoid arthritis and I have found that by eliminating foods belonging to the nightshade family (tomatoes, potatoes, eggplant, peppers and chili) I no longer have the morning stiffness that I found quite painful. Apparently it is the solanine in these foods which caused the morning stiffness (for me anyway). However, these foods are some of my favorites and as I also have a gluten intolerance, I am struggling to find foods to eat.

Is the solanine in a particular part of the vegetable or all through it? I have read that in potatoes, the solanine is found in the skin or if the potato has started to root, where the tuber is growing. New food labels require peanut and soy ingredients to be listed with an allergy warning on the label. So perhaps by carefully skinning the potato I can still eat it? Do you know where the solanine is in tomatoes, eggplants etc., could it be in the seeds or the skin of these vegetables, too?

Many thanks for your help.

Also include tobacco and red peppers in your nightshade list. The green peel, sometimes found on potatoes grown too close to the surface of the ground, contain higher amounts of solanine. Throw away potatoes with any green skin. Other vegetables seem to have solanine throughout. Solanine inhibits nerve impulses.

I have not found any medical research to support your connection between arthritis and eating foods high in solanine or foods belonging to the nightshade family. The National Center for Complimentary and Alternative Medicine cautions against eliminating foods as there is no evidence that any food causes or treats arthritis. My concern is that you are eliminating vegetables with nutrients that contribute significantly to your health. You should include a variety of vegetables, fruits and whole grains in your eating plan.

With a gluten intolerance, none of the foods with solanine have gluten. For specific suggestions based on your eating history, please see the gluten topic and contact a registered dietitian.

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