Rheumatoid arthritis – signs, symptoms & risk factors

Statistics on rheumatoid arthritis (RA) from the World Health Organization1

  • In 2019, 18 million people were reported to be living with RA worldwide
  • 70% of RA cases are women and they are two to three times more likely to be affected than men
  • 55% cases of RA are found in those over 55 years old

In this week’s blog, we look at the signs, symptoms and risk factors associated with rheumatoid arthritis including diet, lifestyle and genetics.

What is rheumatoid arthritis?

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterised by the production of auto-antibodies, activated T cells, continuous synovitis and the presence of rheumatoid factor (RF), alongside chronic joint inflammation and destruction. Over time, inflammation of the synovial membrane lining the synovial joints, known as synovitis, leads to this joint destruction causing pain, swelling, stiffness and the limitation of movement.

Inflammatory conditions such as RA can lead to inflammation developing in other areas of the body such as:

    • Blood vessels (vasculitis) – this can lead to the thickening, narrowing, weakening and scarring of blood vessel walls.
    • Heart – inflammation of the tissue around the heart can lead to pericarditis, causing chest pain.
    • Eyes – inflammation of the eyes can lead to scleritis which can cause eye redness and pain.
    • Lungs – inflammation of the lungs or lung lining can lead to pleurisy or pulmonary fibrosis, which can cause shortness of breath, chest pain and a persistent cough.
    • Spinal cord – there is an increased risk of cervical myelopathy which is the compression on the cervical spinal cord.

Skip to Key Takeaways

Signs and symptoms of RA

  • Joint pain is a common symptom alongside swelling in and around the joints lasting for six weeks or more. The wrists, feet, hands, ankles and knees are most commonly affected by RA, but any joint can be affected
  • Stiffness first thing in the morning, lasting for several hours
  • Fatigue and muscle aches
  • Redness, tenderness, pain and heat around the inflamed joints. This can often be in a symmetrical pattern
  • Limitation of movement such as exercise, walking or bending
  • Some people find that they lose their appetite
  • Low grade fever

Rheumatoid arthritis risk factors


Several lifestyle factors have been shown to play a role in RA risk, including:

  • Smoking—nicotine in the bloodstream can increase rheumatoid factor levels2 and research has found smokers have a 30% higher risk of developing RA.3

Evidence suggests that cigarette smoking can lead to the production of antibodies that are linked to RA development.4 Smoking may also reduce the effect of clinical RA treatments such as disease-modifying antirheumatic drugs (DMARDs).5,6

  • Weight – Obesity is a risk factor for RA development and is associated with disease progression and poor response to treatments. Physical inactivity is both a result of and risk factor for the development of RA and can lead to further adverse health effects such as cardiovascular disease risk.7

It has been proposed that increasing rates of RA could potentially be related to the increase in rates of obesity, but study results have been mixed. Adipocytokines and insulin resistance and their pro-inflammatory effects have been proposed as possible mediators in RA.8


The association of a particular human leukocyte antigen (HLA) with RA was first noted in the late 1970s, when the frequency of individuals with the HLA-Dw4 serotype was found to be increased among RA patients compared with healthy controls.9

Vitamin D deficiency

Epidemiological evidence has shown increased prevalence of several autoimmune diseases, including inflammatory bowel disease, MS, type 1 diabetes and rheumatoid arthritis at Northern latitudes where sun exposure is reduced; therefore, it has been suggested that vitamin D may be protective against autoimmune conditions.10

This is likely to be due to anti-inflammatory and immune modulating effects that vitamin D has demonstrated, such as regulating the production of inflammatory cytokines and inhibiting the proliferation of pro-inflammatory cells, both of which are crucial for the development of inflammatory and autoimmune diseases.

Research suggests that low levels of 25(OH)D may be a risk factor for RA development and disease activity, with supplementation being considered useful due to its effect on suppressing Th1 and Th17 and stimulating Treg activity, which play a role in autoimmunity and inflammation. 11

Dietary sources of vitamin D only provide low levels and most is produced in the skin following sun exposure. In the UK, vitamin D can be synthesised on sunny days between April and September between 10.00 am and 2.00 pm. Although vitamin D cannot be synthesised during the winter at our latitude, it can be stored in the body, however production also depends on factors such as genetics, age, sunscreen, clothing, and skin colour.

Microbiome and leaky gut

The fundamental role the gut microbiota play in health and disease is well established and research strongly suggests that the gut microbiota plays a vital role in RA development and progression. The gut microbiome, in partner with the gut-associated lymphoid tissue maintain immune homeostasis and can influence inflammatory and autoimmune conditions.12

Dysbiosis impacts innate immunological pathways and may trigger the activation of innate immune cells and the production of pro-inflammatory cytokines such as IL-12, IL-23 and type 1 interferons among others, paired with a down regulation of anti-inflammatory cytokines such as transforming growth factor B and IL-10. Studies show that the balance between Th17 and Treg cells is closely related to RA and that this is regulated by the gut microbiota and their metabolites.13,14

Healthy intestines are naturally permeable, allowing tiny nutrient particles to flow through their lining and enter the bloodstream.14 Problems arise if the intestinal lining becomes damaged.  For more information, please read our blog –   Leaky Gut Syndrome – causes, symptoms and routes to repair – Cytoplan

It is understood that celiac disease, type 1 diabetes, multiple sclerosis, rheumatoid arthritis, Crohn’s and several other autoimmune diseases have all been associated with leaky gut.  This allows the passage of antigens from the intestinal flora into the bloodstream which challenges the immune system.15

What foods to eat for rheumatoid arthritis?

Nutritional quality has been shown to impact RA with diet playing a role in the pathogenesis, symptom severity and management of the condition.

The typical western diet, associated with being low in plant foods and high in fat and animal products, alongside a higher ratio of omega 6 to omega 3 fatty acids has been found to be associated with an increased risk of RA.16

Nutritional intervention aims to attenuate inflammation and support antioxidant status by increasing omega 3 fatty acid and plant foods and reducing high intakes of omega 6, animal fats and refined carbohydrates, alongside the reduction or elimination of diary and gluten.

A recent meta-analysis showed significant reduction in pain in RA patients who followed an anti-inflammatory diet17 which is typical of the mediterranean way of eating.

A mediterranean diet (MD) is a predominantly plant-based diet including an abundance of vegetables, fruits, wholegrains, seeds, olive oil and fish, with a lower intake of animal products, processed and refined foods. Adherence to this way of eating has been found to have health promoting, anti-inflammatory and immune modulating effects and is recommended to support cardiovascular function, obesity and inflammatory conditions such as RA.12

High fibre intake is a fundamental aspect of a MD and has been linked to reduced disease activity, potentially in part due to the increase in short chain fatty acids, which are associated with a healthier gut environment and play a part in modulation of dysbiosis, alongside regulating inflammatory markers such as IL-6, TNF-a and plasma CRP, all of which have been found to be triggers of RA.18

Gluten-free diet

Gluten, a food-derived antigen, is the driver of the autoimmunity seen in coeliac disease. Increased intestinal permeability found in coeliac patients, coupled with a genetic predisposition and altered immunological response, may result in a systemic immune response that is directed against sites other than the gut.

Food or gut-derived antigens may have a role in the pathogenesis of other autoimmune disorders including RA.19 While research has found mixed results, a gluten-free diet may offer benefits to patients with RA.20


Flavonoids, found abundantly in foods and beverages of plant origin, such as fruits, vegetables, tea, cocoa and wine, possess antioxidant, antimicrobial, and anti-inflammatory properties. These compounds can play a protective role against atherosclerosis, RA, and other inflammatory conditions. 21

Good dietary sources of flavonoids:

  • Red, blue, and purple berries; red and purple grapes
  • Teas (particularly white, green, and oolong), cocoa-based products
  • Apples
  • Onions, kale, broccoli, apples, berries, teas
  • Parsley, thyme, celery, hot peppers
  • Citrus fruit such as oranges, grapefruits and lemons
  • Legumes

Omega-3 fatty acids

Long-term intake of omega-3 fatty acids have been reported to be protective against the development of RA.  Some studies support the role of omega-3 fatty acid supplementation as a valuable therapeutic option to improve symptoms, tender joint count, duration of morning stiffness, and the requirement for non-steroidal anti-inflammatories in RA.22

Good sources of omega-3 fatty acids:

  • Wild caught salmon (tinned or fresh)
  • Sardines (tinned in olive oil)
  • Herring (tinned or fresh)
  • Flaxseeds
  • Hempseeds
  • Chia seeds
  • Walnuts

Supplements for rheumatoid arthritis

Vitamin D

Vitamin D has been widely studied on its effect on the immune system and evidence suggests that low vitamin D status may be implicated in the pathogenesis of RA. The relationship between vitamin D and RA is complex, with vitamin D deficiency being common, researchers also highlight the increased risk of osteoporosis in RA.23

Omega 3 fatty acids

Omega 3 fatty acids have anti-inflammatory properties that can help to ease symptoms associated with arthritic pain, with many studies demonstrating improvements in pain and morning stiffness after an increase in omega 3 fatty acids. A 2021 systematic review found that dietary interventions in combination with omega 3 supplementation provided additional benefit in symptom management in RA than through dietary change alone.24

Live native bacteria

RA is an autoimmune disease in which probiotics appear to have an immune modulating action, alongside decreasing the inflammatory process. Current evidence supports the role of probiotics as adjunctive therapy in RA, with one study finding that probiotics lowered pro-inflammatory cytokines IL-6.23 Probiotics have been found to reduce inflammation of the intestinal wall, reduce intestinal permeability, modulate the microbiota and have been found to lower inflammatory markers such as CRP.14,26

Anti-inflammatory nutrients

Herbs such as Boswellia serrrata and turmeric have been shown to inhibit pro-inflammatory processes through effects on inflammatory enzymes, suppression of NF-KB activation and the reduction of pro-inflammatory cytokines.

Curcumin has been found in research to improve clinical symptoms of RA and can be used therapeutically to reduce inflammation, pain and swelling. It has also been found to improve dysfunction of the immune cells Th1, Th17, Treg and B cells which all play a role in autoimmunity and enhance anti-rheumatic immunity.27

Boswellia is an Ayruvedic herb that has shown significant activity as a therapeutic tool in RA. Research has shown its use as an anti-inflammatory and anti-arthritic agent that can improve pain, improve mobility and reduce the expression of inflammatory factors such as THF-a and IL-6.28

Bridge the nutrition gap

A deficiency of certain nutrients can have an impact on innate and adaptive immunity, for example, a deficiency in zinc can alter immune cells and contribute to inflammation,29 while vitamin D deficiency is thought to play a role in autoimmune conditions.23

Research has also looked into the role of other nutrients such as vitamin E’s ability to enhance the quality of life for those with RA by reducing joint discomfort and stiffness.30

Therefore, an anti-inflammatory diet alongside a multivitamin and mineral formulation can help bridge the nutrition gap and ensure adequate nutritional status.

What is the difference between rheumatoid arthritis and osteoarthritis?

Rheumatoid arthritis and osteoarthritis are both conditions that share similar symptoms such as joint pain, inflammation, stiffness and loss of movement.

The pathogenesis of RA is autoimmune in nature and occurs when the immune system attacks the synovium leading to swelling and inflammation, this can then impact the health of the individual outside of the joints.

In a healthy joint, cartilage covers the surface of the bones, acting as a shock absorber to allow the bones to move against each other freely. In Osteoarthritis, there is a gradual deterioration and thinning of this cartilage, meaning bones start to rub together. The tissues within the joint become more active in an attempt to repair the damage which can alter the joint structure, in some cases this allows the joint to work without pain, but in many these changes cause pain, swelling and reduces movement.

The causes of OA are unclear with multiple factors such as age, gender, genetics, obesity and injury contributing to the development. You can read more about OA in our blog Osteoarthritis: causes, drivers & interventions for protection | Cytoplan blog

Key takeaways

  • Rheumatoid arthritis is an inflammatory condition which can cause inflammation to develop in other tissues such as lungs, heart, blood vessels, eyes and spinal cord.
  • Symptoms may present as swelling in and around joints, redness, heat and tenderness, morning stiffness, fatigue and muscle aches.
  • Risk factors include smoking, poor diet and food sensitivities, obesity, genetics, hormone imbalance, vitamin D deficiency and imbalance of gut bacteria.
  • For autoimmunity to develop 3 factors are necessary – a genetic predisposition, an environmental trigger, and increased intestinal permeability (also called leaky gut)
  • The Mediterranean diet has been found to be helpful in decreasing pain and disease activity as has a vegan, gluten-free diet
  • Supporting gut health is important, including repair of leaky gut. See our blog Leaky Gut Syndrome – The Signs and Symptoms
  • Other nutrients to consider include flavonoids (found in brightly coloured vegetables and fruit), omega-3 fatty acids (found in oily fish), vitamin D, live native bacteria, Curcumin and Boswellia.


  1. World Health Organization. Rheumatoid arthritis. www.who.int. Published June 28, 2023. https://www.who.int/news-room/fact-sheets/detail/rheumatoid-arthritis
  2. Ishikawa Y, Ikari K, Hashimoto M, et al. Shared epitope defines distinct associations of cigarette smoking with levels of anticitrullinated protein antibody and rheumatoid factor. Ann Rheum Dis. 2019;78(11):1480-1487. doi:10.1136/annrheumdis-2019-215463
  3. Sánchez-Campamà J, Nagra NS, Pineda-Moncusí M, Prats-Uribe A, Prieto-Alhambra D. The association between smoking and the development of rheumatoid arthritis: a population-based case-control study. Reumatol Clin (Engl Ed). 2021;17(10):566-569. doi:10.1016/j.reumae.2020.08.006
  4. Ishikawa Y, Terao C. The Impact of Cigarette Smoking on Risk of Rheumatoid Arthritis: A Narrative Review. Cells. 2020;9(2):475. Published 2020 Feb 19. doi:10.3390/cells9020475
  5. Teitsma XM, Jacobs JWG, Welsing PMJ, et al. Inadequate response to treat-to-target methotrexate therapy in patients with new-onset rheumatoid arthritis: development and validation of clinical predictors. Annals of the Rheumatic Diseases. 2018;77(9):1261-1267. doi:https://doi.org/10.1136/annrheumdis-2018-213035
  6. Safy-Khan M, de Hair MJH, Welsing PMJ, van Laar JM, Jacobs JWG; Society for Rheumatology Research Utrecht (SRU). Current Smoking Negatively Affects the Response to Methotrexate in Rheumatoid Arthritis in a Dose-responsive Way, Independently of Concomitant Prednisone Use. J Rheumatol. 2021;48(10):1504-1507. doi:10.3899/jrheum.200213
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  10. Yin, K. and Agrawal, D. K. (2014) ‘Vitamin D and inflammatory diseases’, Journal of inflammation research. Dove Press, 7, pp. 69–87.
  11. Sîrbe C, Rednic S, Grama A, Pop TL. An Update on the Effects of Vitamin D on the Immune System and Autoimmune Diseases. Int J Mol Sci. 2022;23(17):9784. Published 2022 Aug 29. doi:10.3390/ijms23179784
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  22. Navarini et al., 2017) Navarini, L. et al. (2017) ‘Polyunsaturated fatty acids: any role in rheumatoid arthritis?’, Lipids in health and disease. BioMed Central, 16(1), p. 197.
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  28. Yu G, Xiang W, Zhang T, Zeng L, Yang K, Li J. Effectiveness of Boswellia and Boswellia extract for osteoarthritis patients: a systematic review and meta-analysis. BMC Complementary Medicine and Therapies. 2020;20(1). doi:https://doi.org/10.1186/s12906-020-02985-6
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  30. Kou H, Qing Z, Guo H, Zhang R, Ma J. Effect of vitamin E supplementation in rheumatoid arthritis: a systematic review and meta-analysis. European Journal of Clinical Nutrition. Published online April 25, 2022. doi:https://doi.org/10.1038/s41430-022-01148-9

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Last updated on 24th April 2024 by cytoffice


16 thoughts on “Rheumatoid arthritis – signs, symptoms & risk factors

  1. Hello
    I have Rheumatoid Arthritis and do not take medication but a whole lot of supplements prescribed by my nutritionist and am doing relatively well. I am interested to know if any research has been done into the use of bicarbonate of soda in general and in particular for RA. I have recently started taking 1t dissolved in a glass of water every day and feel that it is helping.

    1. Hi Judy,

      Many thanks for your comment on our blog. There is indeed some research that has been done in this area, I will send you some links to read up on these via e-mail today.

      All the best,

        1. Hello Margaret,
          Thank you for your comment. I have have spoken with our team and I can confirm this blog has recently been updated and the references at the bottom of the page are what you should need.

  2. My daughter 41 yrs, was diagnosed with RA with bloods showing several very high levels of Rheumatoid factor 2 years ago. 12 yrs before she had 2 sets of twins with 3 survivors; this followed by a divorce and major work changes. Stress levels were sky high but her coping mechanisms appeared good. Joint issues appeared quite early on – e.g. RST in both hands; but then she was on keyboards most of time… aching joints – but then she’d been running/lifting/carrying: always an answer. Sleep poor, Living as a vegetarian since she was 18 she was really a “fast food veggie” with lots of dairy, processed soya etc rubbish tho quite good range of veg. Long story short after RA diagnosis she asked for my help and I put on her a semi-vegan diet but including eggs & fish oil caps, no wheat. Good improvements and no methotrexate. UNKNOWN MAJOR GUT ISSUES DEALT WITH. Listening to her body, she discovered Om 3 &/or EP oils made her WORSE & she reacted to eggs even if blind. Wheat doesn’t affect her. Totally healthy eating vegan now for about a year, 3 weeks ago the doc can now find, to his total amazement, no evidence whatsoever in either her blood of RA or physical symptoms whatsoever. This was the doc who said she’s be in a wheel chair within 2 yrs if she didnt take methotrexate. ….
    I know shes not the only ‘recoverer’ from RA/A-I conditions on whole foods but, as a naturopath treating my own daughter who’s been thru so much, I’m ever grateful for the sharing of research which facilitated me to help her & trust “the instinct”. She gets married next week and her 3 surviving children (now 13 and 2 x 12) are happy, healthy and gorgeous grandchildren !

    1. Thank you for your story.My niece has just been diagnosed with RA. I will pass this article o. To her. It gives us hope Blessings

  3. Hey my name is Dee i am 53 yes old i have rheumatoid arthritis my hands ,feet, and my lower back is paining me .i have this lower back pain for so long and fingers . So now i need some help on what food i should be eating . Thanks

    1. Hi Dee – I am glad it was helpful. Yes dietary interventions that aim to reduce inflammation are useful for arthritis.

  4. Hi my name is ejaz ahmed i am from pakistan i also have the same problem felling pain in all joints of my body and my serum crp is 1.98 high can you guide me

  5. Hi,one year ago I sprain my ankle and now going to take covid vaccine next month ,can I still take covid vaccine?
    I have went to physiotherapy fee sections n stopped last year, however last week my ankle hurts due to I repeatedly exercise with walking on tread mill and cycling .
    Please advise as now feel stiffness at my ankle

    1. Hi Patricia – There are a few supplements than can help with stiffness and pain in the joints including anti-inflammatory products such as Boswellia or Cell Active Curcumin Plus, or our Cytoprotect Joints which is designed to support overall joint health, particularly in those with an active lifestyle. If you would like to discuss the most relevant products for you, please contact our Nutritional Therapists on nutrition@cytoplan.co.uk

  6. My sister is 35years having rheumatoid arthritis for 20years now she been under Medication for all those years but no improvement now using Diclofenac as pain reliever how can she get help pliz

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