Younger adults in America's famous Blue Zone are eating differently

By Hugo Francisco de SouzaReviewed by Susha Cheriyedath, M.Sc.Nov 2 2026

In one of the world's best-known longevity communities, researchers examined how age, religious traditions, and eating habits intersect, raising questions about whether the next generation will maintain the lifestyle associated with its remarkable reputation.

Study: Generational Adherence to Vegetarian Diets in the Loma Linda Blue Zone and Surrounding Areas: A Cross-Sectional Study Between Adventist and Non-Adventist Populations. Image Credit: SevenMaps / Shutterstock

In a recent cross-sectional study published in the American Journal of Lifestyle Medicine, researchers evaluated self-reported dietary habits and body mass index (BMI) among 615 adults surveyed in the Loma Linda Blue Zone area and surrounding Southern California communities.

The study aimed to assess whether adherence to the region’s traditional plant-based vegetarian diet differs by age group. The study findings revealed that vegetarianism was more common among older adults and Seventh-day Adventist (SDA) members, and that vegetarians exhibited significantly lower BMI than their non-vegetarian counterparts.

The analyses identified significant age-related differences in vegetarian habits, raising questions about the preservation of the region's historic longevity practices and highlighting the need for further research and community health promotion.

Background

“Blue Zones” are terms used to describe geographic regions recognized globally for exceptional concentrations of centenarians (individuals living to 100 years or older) and lifestyles associated with healthier aging.

While several Blue Zones around the world have been identified, reviews of these regions’ underlying lifestyles indicate distinct cultural and environmental influences associated with their unusual longevity. For example, researchers propose that while regions such as Sardinia and Okinawa maintained traditional lifestyles partly through geographic isolation, Loma Linda instead represents a community-driven model rooted in the health principles of the Seventh-day Adventist Church.

Historical records show that for more than 160 years, church guidelines have advocated plant-forward nutrition emphasizing legumes, whole grains, and nuts, along with abstinence from tobacco and alcohol, regular physical activity, and social connection, practices believed to contribute to the population's Blue Zone characteristics.

The researchers have raised concerns that longevity regions increasingly face dietary westernization, with fast-food establishments entering Loma Linda around 2013 providing one example of a changing food environment. Whether younger generations maintain traditional vegetarian practices remains underexplored, limiting understanding of how the region’s dietary traditions might change over time.

About the study

The present study aimed to address this knowledge gap and inform future community health efforts by evaluating dietary patterns, BMI, and religious affiliation across age groups in the Loma Linda region. The study was conducted by Loma Linda University's Office of Preventive Care and involved surveying 615 adults at health fairs and community events in Loma Linda and nearby communities in San Bernardino and Riverside counties.

The study collected dietary and demographic information using participant-completed questionnaires. The dietary segments of these questionnaires categorized participants as vegetarians (vegans, lacto-ovo vegetarians and pescatarians) or non-vegetarians. As pescatarians consume fish, the vegetarian category was broader than definitions that exclude all fish and meat.

The study recorded participants’ self-reported denominational status (SDA versus non-SDA) and calculated BMI from self-reported height and weight. For downstream analyses, the study stratified participants into three age brackets: younger adults (18 to 35 years), middle-aged adults (36 to 65 years), and older adults (66 years or older).

The researchers compared dietary patterns, BMI, and religious affiliation across age groups. Because the surveys were completed voluntarily and participants’ residential addresses were not recorded, the researchers could not determine how many lived within Loma Linda itself.

Study findings

The study’s analyses revealed that 39.0% of participants followed a vegetarian diet. Dietary pattern was strongly associated with religious affiliation: 81.3% of vegetarians identified as SDA, whereas 61.6% of non-vegetarians were non-SDA.

Among SDA participants, 57.5% were vegetarian, compared with 16.3% among non-SDA participants. The latter figure was roughly three times the United States national estimate cited in the paper (approximately 6%). The authors suggested that local health culture could influence dietary choices, but differences in definitions and sampling limit direct comparison, and cultural influence was not directly tested.

Age-group analyses revealed differences in vegetarian dietary patterns. Vegetarians were significantly older than their non-vegetarian counterparts (mean age 62.9 vs. 58.3 years), and 26.7% of adults aged 18 to 35 were vegetarian, compared with 41.9% of those aged 36 to 65 and 42.1% of those aged 66 or older.

Within the Adventist subgroup, vegetarians were older on average than non-vegetarians (63.3 versus 54.4 years). Among non-SDAs, vegetarians and non-vegetarians were similar in age, suggesting that religious traditions may explain the age differences. The researchers noted that duration of church membership or adherence to a particular diet could also contribute to these patterns.

Finally, the study identified an association between dietary pattern and BMI. Vegetarians had a significantly lower mean BMI than non-vegetarians (24.8 kg/m² vs. 27.0 kg/m²), with 60.4% within the normal BMI range compared with 40.0% of non-vegetarians.

Obesity was also more common among non-vegetarians. Lower mean BMI among vegetarians was recorded within both SDA and non-SDA groups, but the analyses did not establish whether the differences were independent of age, sex or other lifestyle factors.

Across age groups, mean BMI among non-SDAs ranged from 26.0 to 27.5 kg/m², with no statistically significant difference. SDA members had a mean BMI of 24.5 kg/m² in younger adulthood, 26.0 kg/m² in middle age and 25.2 kg/m² in older age, with significant variation across groups. These comparisons represent different participants, not changes in body weight followed over time.

Conclusions

The study indicates that vegetarian dietary patterns among surveyed adults in the region were associated with lower BMI, consistent with earlier research on body weight. The observed age-related differences in vegetarian adherence raise questions about whether younger adults are abandoning traditional habits, but cannot establish a decline over time or erosion of the community’s longevity advantage. Voluntary recruitment, self-reported data, and uncertainty about participants’ residence further limit the conclusions. The authors recommend longitudinal research and community health promotion.