The EPIC-Oxford Study

The Study

EPIC-Oxford is the Oxford component of the European Prospective Investigation into Cancer and Nutrition (EPIC). Recruitment began in 1993, and approximately 65,000 men and women throughout the United Kingdom joined the original cohort.

Links to This Study

• Official EPIC-Oxford website — University of Oxford
  The University of Oxford’s official EPIC-Oxford page explains the study’s history, purpose, participants, findings, and current expansion.
• Recruitment and data collection — University of Oxford
  This official page explains how participants were recruited, how dietary groups were defined, what information was collected, and how EPIC-Oxford fits within the larger European EPIC collaboration.

What Is EPIC?

EPIC stands for the European Prospective Investigation into Cancer and Nutrition. The larger European collaboration includes more than 500,000 participants from 10 European countries.

EPIC-Oxford is one component of this much larger research program.

Why Is EPIC-Oxford Especially Interesting?

Researchers deliberately recruited participants with a wide range of dietary patterns, with particular efforts to include vegetarians and vegans.

This resulted in an unusually large population of people who do not eat meat, making EPIC-Oxford particularly valuable for studying the long-term health of vegetarian and vegan diets.

Who Participated?

Approximately 65,000 men and women living throughout the United Kingdom were recruited into EPIC-Oxford beginning in 1993.

Participants included meat eaters, fish eaters who did not eat meat, vegetarians, and vegans.

How Were the Dietary Groups Defined?

Participants answered questions about whether they ate meat, fish, dairy products, and eggs. Researchers used these answers to classify people into broad dietary groups.

The cohort included approximately 34,000 meat eaters, 10,000 fish eaters, 19,000 vegetarians, and several thousand vegans.

How Have Participants Been Followed?

Researchers have used repeat questionnaires and linkage to National Health Service medical records to follow participants’ diets and health over decades.

Many participants also provided blood samples, allowing researchers to examine biomarkers as well as reported dietary patterns and health outcomes.

What Health Outcomes Have Researchers Studied?

EPIC-Oxford researchers have investigated cancer, cardiovascular disease, diabetes, obesity, fractures, mortality, and many other health outcomes.

The cohort has generated a large body of scientific research rather than one single EPIC-Oxford paper.

One Important Description of the Cohort

A 2003 paper described the lifestyle characteristics and nutrient intakes of 65,429 EPIC-Oxford participants, including 33,883 meat eaters and 31,546 non-meat eaters.

Links to the Cohort Paper

• PubMed record
  The U.S. National Library of Medicine’s record for the paper describing the dietary and lifestyle characteristics of the EPIC-Oxford cohort.
• DOI — permanent study identifier
  The DOI is the paper’s permanent digital identifier and provides a durable route to the published article.

What Has EPIC-Oxford Found About Plant-Based Diets?

The findings are complex rather than uniformly favorable or unfavorable. Researchers have reported lower risks of several conditions among vegetarians compared with meat eaters, including obesity, ischaemic heart disease, and diabetes.

Other analyses have identified possible risks that deserve attention, including higher rates of fractures and some types of stroke in certain non-meat-eating groups.

Why Are Those Mixed Findings Important?

A dietary pattern can have both potential benefits and potential nutritional vulnerabilities. For example, researchers have investigated whether differences in body weight or intakes of protein, calcium, vitamin B12, vitamin D, and other nutrients may help explain some findings.

This makes EPIC-Oxford particularly useful for studying not only whether plant-based diets are associated with health outcomes, but also how those diets may need to be planned to support long-term health.

One Important Cardiovascular Paper

A 2019 analysis examined ischaemic heart disease and stroke among meat eaters, fish eaters, and vegetarians over approximately 18 years of follow-up.

• PubMed record — heart disease and stroke analysis
  The U.S. National Library of Medicine’s record for the prospective EPIC-Oxford analysis comparing cardiovascular outcomes among different dietary groups.

An Important Limitation

EPIC-Oxford is observational. Researchers did not randomly assign people to remain vegan, vegetarian, pescatarian, or meat eating for decades.

People who choose different diets may also differ in smoking, exercise, education, body weight, supplement use, and many other characteristics. Researchers statistically adjust for many of these differences, but observational studies cannot eliminate every possible confounding factor.

What Is Happening to EPIC-Oxford Now?

More than 30 years after recruitment began, EPIC-Oxford is entering a major new phase.

Researchers plan to resurvey surviving participants and recruit approximately 80,000 additional people, with particular emphasis on increasing the number of participants following vegan and other plant-based diets and increasing the diversity of the cohort.

The expansion is expected to create a cohort of approximately 145,000 participants.

Why Is This Included Under “What Happens Over a Lifetime?”

EPIC-Oxford has followed people with very different habitual diets for decades.

That long perspective allows researchers to examine both the potential benefits and potential risks associated with dietary patterns maintained over substantial portions of adult life.