Authors:
Associate Prof. Gernot Keyßer (University Hospital Halle - Saale), Prof. Monika Reuß-Borst (Rheumatology Practice, Bad Bocklet), Prof. Andreas Michalsen, Dr. Inna Frohne (University Hospital Düsseldorf), Dr. Mandy Gläß (Vogelsang-Gommern Rheumatology Clinic), PD Alexander Pfeil (University Hospital Jena), Assistant Prof. Dr. Oliver Sander (University Hospital Düsseldorf), Prof. Olga Seifert, Dr. Olaf Schultz (Baden-Baden Rheumatology Clinic), Commission for Complementary Therapies and Nutrition
The term “Mediterranean diet” (MD) describes traditional dietary habits in the Mediterranean region. These vary widely depending on the country and region, but share important common elements [18]. These include
1.) a high proportion of plant-based foods: fruits, vegetables, legumes, nuts, bread, and grains
2.) olive oil as the primary source of fats, and a low proportion of saturated animal fats (e.g., butter and lard)
3.) dairy products in the form of cheese, yogurt, and kefir
4.) Fish and poultry in varying amounts, but in smaller proportions compared to the average “Western” diet, with a significantly reduced proportion of “red” meat
5.) A significantly reduced amount of white sugar and high-fructose corn syrup (found, for example, in soft drinks)
5.) Optional: Moderate wine consumption (no more than 10g of alcohol per day) with meals
This dietary pattern allows for variety, can be very tasty, and has been well-studied scientifically.
Adherence to the ME can be quantified using scoring systems. One such system is the Alternate Mediterranean Diet Score (AMDS). This system assigns positive values to the proportions of positively rated food components—such as vegetables, legumes, and nuts—and negative values to negatively rated components (e.g., red meat) [15]. In cross-sectional studies, a high score is associated with a significantly better probability of survival [15], as well as a reduced likelihood of heart attack and stroke [5]. High adherence to the ME is associated with lower incidences of metabolic diseases and obesity (review in [3]). In the longitudinal Nurses’ Health Study, shifting from an average “Western” diet toward a higher AMDS score was correlated with improvements in overall mortality and mortality from cardiovascular causes [14]. A large prospective study on the primary prevention of cardiovascular events demonstrated a protective effect of the ME, particularly when the diet was enriched with olive oil and nuts [4]. A Mediterranean diet also reduces the risk of cancer, particularly colorectal cancer [9]. Whole grains, vegetables, and fruits have the greatest impact here, as does low alcohol consumption with meals [9].
Scientific publications on the influence of the ME on disease risk and progression are available for only a few rheumatic diseases, which are summarized here:
Rheumatoid arthritis (RA)
In a Swedish cohort study, the AMDS was inversely correlated with the risk of seropositive RA [8]. High adherence to the ME reduced the risk of RA by 21% compared with low adherence; however, the effect was statistically significant only in men [8]. Similarly, in the Nurses’ Health Study, involving over 170,000 women, no correlation between the AMDS and the risk of RA was detected [6].
In patients with established RA, an ME led to a slight but significant improvement in inflammatory activity, as measured by DAS28 and patient-reported outcomes (PROs), including the Health Assessment Questionnaire and the visual analog scale for pain, in a controlled intervention study [13].
In another study, RA patients were placed on a precisely defined anti-inflammatory diet explicitly based on the principles of the ME (Anti-Inflammatory Diet in RA, ADIRA study). Here, too, improvements in DAS28 and some PROs were demonstrated over the course of the intervention, even though the changes were modest and narrowly failed to reach statistical significance compared to a control group [16, 17]. The diet led to a highly significant improvement in lipid metabolism parameters, resulting in a less atherogenic lipid profile [7].
Psoriatic arthritis (PsA)
There is only indirect evidence of a possible association between ME and PsA incidence: In psoriasis vulgaris, the severity of skin manifestations [11], and in overt PsA, arthritic activity [2], are inversely correlated with adherence to the principles of ME.
Spondyloarthropathies (SpA)
Training SpA patients in the application of the ME led to mild improvements in disease activity, as measured by the ASDAS-CRP1 [10]
Systemic lupus erythematosus (SLE)
The risk of developing SLE does not appear to be influenced by overall dietary quality or adherence to the ME [1]. In patients with established SLE, adherence to the ME was associated, in a cross-sectional study, with lower cardiovascular risk factors, lower SLE activity as measured by the SLEDAI2 , and less disease-related damage [12].
1 Ankylosing Spondylitis Disease Activity Score with C-reactive Protein
2 Systemic Lupus Disease Activity Index
For patients with the aforementioned conditions, ME can be recommended as an adjunct to basic antirheumatic therapy due to the described positive effects on disease activity. In addition, ME can be recommended for all rheumatic diseases—including those not listed here—due to its positive effects on the cardiovascular risk profile and the incidence of metabolic comorbidities.
When used properly, no adverse effects are to be expected. The ME is not equivalent to a vegan diet; therefore, additional supplementation—e.g., with vitamin B12—is not necessary. Although the risk that patients with a strong affinity for complementary medicine might wish to “replace” necessary drug therapy with a dietary change is low, it should be taken into account.
The Commission recommends that rheumatologists generally suggest the ME to all patients who are under long-term care for inflammatory rheumatic diseases and provide them with appropriate informational materials. This applies particularly to patients with additional risk factors for cardiovascular disease. Training programs offered by patient self-help groups or the option of referral to professional nutritional counseling for the ME should be utilized. Such an intervention is not strictly necessary if the patient already follows a largely plant-based diet that meets the requirements for a health-promoting diet.
1. Barbhaiya M, Tedeschi S, Sparks JA et al. (2021) Association of Dietary Quality With Risk of Incident Systemic Lupus Erythematosus in the Nurses’ Health Study and Nurses’ Health Study II. Arthritis Care & Research 73:1250-1258
2. Caso F, Navarini L, Carubbi F et al. (2020) Mediterranean diet and psoriatic arthritis activity: a multicenter cross-sectional study. Rheumatology International 40:951-958
3. Dominguez LJ, Di Bella G, Veronese N et al. (2021) Impact of the Mediterranean Diet on Chronic Noncommunicable Diseases and Longevity. Nutrients 13
4. Estruch R, Ros E, Salas-Salvadó J et al. (2018) Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts. The New England Journal of Medicine 378:e34
5. Fung TT, Rexrode KM, Mantzoros CS et al. (2009) Mediterranean Diet and Incidence of and Mortality from Coronary Heart Disease and Stroke in Women. Circulation 119:1093-1100
6. Hu Y, Costenbader KH, Gao X et al. (2015) Mediterranean diet and incidence of rheumatoid arthritis in women. Arthritis Care & Research 67:597-606
7. Hulander E, Bärebring L, Turesson Wadell A et al. (2021) Dietary intervention improves the cardiovascular profile in patients with rheumatoid arthritis: results from the randomized controlled crossover trial ADIRA. Nutrition Journal 20:9
8. Johansson K, Askling J, Alfredsson L et al. (2018) Mediterranean diet and risk of rheumatoid arthritis: a population-based case-control study. Arthritis Research & Therapy 20:175
9. Morze J, Danielewicz A, Przybyłowicz K et al. (2021) An updated systematic review and meta-analysis on adherence to the Mediterranean diet and risk of cancer. Eur J Nutr 60:1561-1586
10. Ometto F, Ortolan A, Farber D et al. (2021) The Mediterranean diet in axial spondyloarthritis: an observational study in an Italian monocenter cohort. Arthritis Research & Therapy 23:219
11. Phan C, Touvier M, Kesse-Guyot E et al. (2018) Association Between the Mediterranean Anti-inflammatory Dietary Profile and Severity of Psoriasis: Results From the NutriNet-Santé Cohort. JAMA Dermatology 154:1017-1024
12. Pocovi-Gerardino G, Correa-Rodríguez M, Callejas-Rubio J-L et al. (2020) Beneficial effect of the Mediterranean diet on disease activity and cardiovascular risk in patients with systemic lupus erythematosus: a cross-sectional study. Rheumatology 60:160-169
13. Sköldstam L, Hagfors L, Johansson G (2003) An experimental study of a Mediterranean diet intervention for patients with rheumatoid arthritis. Annals of the Rheumatic Diseases 62:208-214
14. Sotos-Prieto M, Bhupathiraju SN, Mattei J et al. (2017) Association of Changes in Diet Quality with Total and Cause-Specific Mortality. The New England Journal of Medicine 377:143-153
15. Trichopoulou A, Costacou T, Bamia C et al. (2003) Adherence to a Mediterranean Diet and Survival in a Greek Population. New England Journal of Medicine 348:2599-2608
16. Turesson Wadell A, Bärebring L, Hulander E et al. (2021) Effects on health-related quality of life in the randomized, controlled crossover trial ADIRA (Anti-inflammatory Diet In Rheumatoid Arthritis). PLoS ONE 16:e0258716
17. Vadell AKE, Bärebring L, Hulander E et al. (2020) Anti-inflammatory Diet in Rheumatoid Arthritis (ADIRA)—a randomized, controlled crossover trial indicating effects on disease activity. The American Journal of Clinical Nutrition 111:1203-1213
18. Willett WC, Sacks F, Trichopoulou A et al. (1995) Mediterranean Diet Pyramid: A Cultural Model for Healthy Eating. The American Journal of Clinical Nutrition 61:1402s–1406s
Last updated: April 18, 2023