I suspect one reason that some medical professionals are reluctant to accept that nightshade vegetables might do harm is the star power of the Mediterranean Diet over the last 25 years. Some of the deep cultural roots of this dietary dominance stretch back millennia, to the trade routes, maritime skills, and agricultural traditions that helped forge the Mediterranean basin as a cradle of civilization. Some are more recent, because it wasn’t until after Christopher Columbus that nightshades—peppers, tomatoes, potatoes, and eggplant—could have become conrnerstone vegetables in the wide range of Mediterranean cuisines.
Diet science didn’t engage until after Wold War 2, with a series of epidemiological studies that examined diet and health outcomes across a variety of cultures. The dietary winners were olive oil over animal fat, seafood over red meat, a frugal serving of red wine with meals, and vegetables over all. Cultures that, through habit or circumstance, followed these general rules had the “lowest rates of chronic diseases in the world and the highest longevity.”1
The first pointer to the benefits of the Mediterranean diet came with a 1948 Rockefeller Foundation study in Crete. A few years later University of Minnesota physiologist Ancel Keys helped unlock the dietary secrets with the Seven Countries Study that began in 1952 and followed the health of almost 12,000 middle-aged men in the United States, Japan, Italy, Greece, the Netherlands, Finland, and then-Yugoslavia. When his group drilled down through the Grecian data into Crete, they discovered lower levels of cardiovascular disease, which they attributed to the “poor” postwar diet of fruits, vegetables, grains, beans, and fish. Keys and his wife publicized some of the dietary findings in cookbooks in 19592 and 1967.3 Not until 1975 did they attempt to cash in on the emerging brand, with How to Eat Well and Stay Well the Mediterranean Way. But it wasn’t until the mid 1990s that continuing long-term studies aligned with culinary trends, launching a thousand cookbooks and heart-healthy entrees.
A wide range of studies has since documented health benefits of the traditional Mediterranean diet, suggesting correlations with everything from increased life span and better brain function to lower risks of heart disease, Alzheimer’s disease, diabetes, and some cancers.
It’s lost a touch of academic luster in recent years. In 2017 a major statistical review of 5,000 studies4 included a pivotal 2013 paper5 on cardiovascular disease and the Mediterranean diet among its list of flawed analyses. The implication: correlations between the Mediterranean diet and cardiac health were not perhaps as strong as originally reported. The 2013 study was retracted, and a more measured analysis replaced it in 2018.6 Another study suggests that the real variable being measured is wealth.7
The rise of the Mediterranean diet has powered markets for specialty foods like olive oil and heirloom tomatoes and inspired countless chefs at home and in professional kitchens. It’s also laid down a foundation of nutritional research over the last several decades. In the early 1990s development of the Dietary Approaches to Stop Hypertension (DASH) diet was likely informed by intensive study of the Mediterranean diet. In the multiple ratings of diet plans that show up around New Years, the Mediterranean and DASH diets usually rank in the upper echelon. And there is enough overlap between the two approaches that there are multiple cookbooks combining both approaches.
More recent dietary research is focused on the underlying biology of inflammation. “A large and growing body of evidence indicates that dietary modifications can have a significant impact on this chronic, low-grade inflammatory state,” argue Wendy Kohatsu and Scott Karpowicz in their chapter “Antiinflammatory Diet” in the 4th edition of Integrative Medicine, a leading textbook in the field. Kohatsu and Karpowicz build their discussion of inflammation and diet around the Mediterranean diet as the archetypal antiinflammatory diet: “there are many different diets that possess antiinflammatory effects,” but the Mediterranean diet is perhaps the best researched.8
Mediterranean cooking encompasses dozens of culinary traditions, and features a creative cavalcade of flavors. Many recipes on this site are dedicated to imitating at least part of its palette, albeit without nightshades. And while the science behind the Mediterranean diet is still a work in progress, the clear consensus is that this approach is above average for human health.
How does this fit with a nightshade sensitivity? I would argue that just because a diet is generally good for most people doesn’t mean that certain parts of that diet are good for all people.
Let’s pretend that 1 in 100 are highly intolerant of nightshades while another 4 in 100 have less severe reactions, but still suffer some overall negative affects.
In fact, if nightshades cause problems for some people, a Mediterranean diet that doesn’t trim these out could actually be a bad choice. Ultimately, that’s not a knock on health effects of the Mediterranean diet for most people. If nightshade sensitivity exists, removing these individuals from the study pool would actually further strengthen the results for those who are nightshade tolerant.
- “Historical origins of the Mediterranean Diet, Regional Dietary Profiles, and the Development of the Dietary Guidelines” in Mediterranean Diet: Dietary Guidelines and Impact on Health and Disease
- Eat Well & Stay Well
- The Benevolent Bean
- “Data fabrication and other reasons for non-random sampling in 5087 randomised, controlled trials in anaesthetic and general medical journals”
- “Primary Prevention of Cardiovascular Disease with a Mediterranean Diet”
- “Following charges of flawed statistics, major medical journal sets the record straight”
- “High adherence to the Mediterranean diet is associated with cardiovascular protection in higher but not in lower socioeconomic groups: prospective findings from the Moli-sani study”
- page 869, Integrative Medicine