Evidence-Based Nutrient Recommendations

Disease Rates of Vegetarians: Cataracts • Diverticular • Gallstones


Tsui Health Study: Cataracts (2021)

A prospective cohort study from Taiwan investigated the association between vegetarian diet and cataract risk (Chiu, 2021). The study analyzed 4,436 participants who were at least 40 years old with no history of cataracts, the majority of whom were Buddhist volunteers (who abstain from smoking and alcohol and are encouraged to eat vegetarian). Participants were followed for an average of 5.7 years. There were 1,341 vegetarians and 3,095 nonvegetarians.

A vegetarian diet was associated with a 20% lower risk of cataracts (HR 0.80, CI 0.65-0.99; P=0.04) after adjusting for sex, education, alcohol, smoking, physical activity, comorbidities, body mass index, and Buddhist volunteer status. When analyzed by body mass index (BMI), the association between vegetarian diet and cataract risk was significant for participants with a BMI of 24 kg/m2 or greater (HR 0.70, CI 0.50-0.99; P=0.04), but not for those with a BMI less than 24 kg/m2 (HR 0.86, CI 0.65-1.14; P=0.29).

EPIC-Oxford: Cataracts (2011)

In a case-control analysis of EPIC-Oxford participants ≥40 years old, a significantly lower risk of cataracts was found in vegetarians than meat-eaters (Appleby, 2011). Vegans had a 40% lower risk of cataracts than those eating more than 100 g/day of meat.

Incidence of Cataracts in EPIC-Oxford (2011)
High Meat Medium Meat Low Meat Pesco Lacto-Ovo Vegan
Cases 329 489 301 148 198 19
Incidence 1.00 .96 (.84-1.11) .85 (.72-.99) .79 (.65-.97) .70 (.58-.84) .60 (.38-.96)
11.4 years follow-up. Adjusted for age, smoking, ethnicity, self-reported prior high blood pressure, long-term medical treatment, hormone replacement therapy, sex, method of recruitment, and region. Meat intake: high is ≥100 g/d, medium is 50-99 g/d, low is >50 g/d.

Source: Appleby, 2011

EPIC-Oxford: Diverticular Disease (2011)

After a mean follow-up time of 11.6 years, EPIC Oxford found that vegetarians had a 31% lower risk of diverticular disease compared with meat-eaters (0.69, 0.55-0.86; Crowe, 2011).

EPIC-Oxford: Gallstones (2017)

After a mean follow-up time of 13.8 years and after adjusting for a number of variables including smoking and alcohol intake, EPIC-Oxford found no significant difference in the risk of symptomatic gallstone disease in vegetarians compared to meat-eaters (McConnell, 2017). When a further adjustment was made for body mass index (BMI), vegetarians had a higher risk (1.22, 1.06-1.41) for symptomatic gallstone disease compared to non-vegetarians. Among both vegetarians and non-vegetarians, those with the highest BMI had the highest risk of developing the disease.


Last updated: January 2018.

Appleby PN, Allen NE, Key TJ. Diet, vegetarianism, and cataract risk. Am J Clin Nutr. 2011 Mar 23. [Epub ahead of print] (Link)

Chiu THT, Chang CC, Lin CL, Lin MN. A Vegetarian Diet Is Associated with a Lower Risk of Cataract, Particularly Among Individuals with Overweight: A Prospective Study. J Acad Nutr Diet. 2021 Apr;121(4):669-677.e1.

Crowe FL, Appleby PN, Allen NE, Key TJ. Diet and risk of diverticular disease in Oxford cohort of European Prospective Investigation into Cancer and Nutrition (EPIC): prospective study of British vegetarians and non-vegetarians. BMJ. 2011 Jul 19;343:d4131.

McConnell TJ, Appleby PN, Key TJ. Vegetarian diet as a risk factor for symptomatic gallstone disease. Eur J Clin Nutr. 2017;71:731-5.