by Jack Norris, RD • Last updated May 2017
EPIC-Oxford is a cohort study of “generally health-conscious” British residents, and it follows large numbers of vegetarians (3). This assessment was conducted in 2010.
Tracking nutrient intakes can give us an idea of how vegans, on average, typically eat and if they’re meeting nutrient requirements. However, there are some drawbacks to these reports:
- The nutrient intakes are based on food frequency questionnaires (FFQ). FFQ are more useful for judging relative nutrient intakes between groups than for measuring absolute amounts of nutrients for comparison to dietary recommendations.
- FFQ don’t include all the foods vegans typically eat, and in the case of EPIC-Oxford, it’s likely they don’t accurately reflect typical portion sizes either. This could explain why a much higher percentage of vegans reported calorie intakes that were implausibly low (43% and 33% of vegan men and women, respectively, compared to 33% and 19% of meat-eating men and women).
- Nutrients amounts are estimated from nutrient database tables rather than directly measuring the nutrient content of the food. Direct measurements are very expensive to perform.
- Nutrients from fortified foods—such as vitamin B12 fortified foods—are rarely accounted for, nor are supplements.
Given all these potential problems, the studies should mainly be used to spot glaring problems or trends.
The table below notes the most interesting findings from this current report.
|Nutrient Intakes in EPIC-Oxford (2016)|
|Saturated Fat (%)||10||10||7||10||9||7|
|Men & Women|
|Vitamin A (RAE)||1,042||701||623|
Calcium intakes for vegans were significantly higher than the previous EPIC-Oxford report from 2003 (see below).
Vitamin A and zinc are a little low according to this data. The DRI for vitamin A is 900 RAE for men and 700 RAE for women. The RDA for zinc is 11 mg for men and 8 mg for women. I also prefer to see vegan protein intakes higher than the .9 g/kg of body weight (for men). But given that the overall food intake reported for vegans was low, intakes of these nutrients were probably a bit higher than reported. Still, these are nutrients I consider to be important for vegans and if you don’t know much about them, please check out the VeganHealth.org articles, Vitamin A and Zinc.
The EPIC-Oxford report includes information on supplement intake, indicating that 50% of vegans were supplementing with vitamin B12.
Table 1 below shows the nutrient intakes of participants in EPIC-Oxford (1). Notes on this data:
- Did not include supplements, but did include fortified foods.
- Vitamin A is listed as measured in micrograms of retinol, rather than retinol activity equivalents (RAE). Plant foods do not contain retinol, yet vegans are listed as having an intake of retinol. But that intake seems very low compared to what would be expected if carotenoids were included. So, it is unclear how the amount of vitamin A was determined.
Adventist Health Study-2 (2013)
Taable 1 below also shows nutrient intakes from Adventist Health Study-2 (AHS-2) (2). Notes on this data:
- Data includes fortified foods and supplements. No separate analysis was given without supplements included.
These nutrient intakes were based on food frequency questionnaires (FFQ) which are the least accurate way of measuring nutrient intakes. FFQs involve asking someone how often they eat a long list of foods. Two better ways to measure nutrient intakes are to ask participants to keep a food diary, or to analyze duplicate portions in a laboratory. EPIC-Oxford has plans to report nutrient intakes by using food dairies among a sample of the population. The authors reported that:
Seven-day food diaries were completed by 31,000 participants and these will provide further information on energy intake. Preliminary analysis of a sample of 150 food diaries indicates that the FFQ does indeed underestimate intakes of energy, and therefore of most nutrients, among vegans (unpublished data).
|Table 1. Nutrient Intakes|
|Men||Women||Men & Women|
|Sat Fat (g)||26||22||22||11||22||19||19||10||19||17||15||16||11|
|Sat Fat %||11||9||9||5||10||9||9||5||9||8||7||7||5|
|Vit A – retinol (mcg)||740||337||306||74||654||308||277||77||–||–||–||–||–|
|Vit B1 – thiamin (mg)||2||2||2||2||2||2||2||2||–||–||–||–||–|
|Vit B2 – riboflavin (mg)||2||2||2||2||2||2||2||2||–||–||–||–||–|
|Vit B3 – niacin (mg)||25||22||21||24||23||20||18||21||–||–||–||–||–|
|Vit B6 (mg)||2.3||2.1||2.0||2.2||2.2||2.0||1.9||2.1||3.1||3.4||3.5||3.3||3.2|
|Vit B12 (mcg)||7.3||5.0||2.6||0.4||7.0||4.9||2.5||0.5||7.1||8.3||8.5||8.0||6.3|
|Vit C (mg)||119||130||123||155||138||147||147||169||250||273||308||271||293|
|Vit D (mcg)||3.4||2.9||1.6||0.9||3.3||2.8||1.5||0.9||6.1||5.5||5.8||4.6||2.4|
|Vit E (mg)||11.8||13.0||13.7||16.1||10.7||11.4||11.6||14.0||20.0||26.1||26.9||24.7||18.5|
|Numbers listed are the average for EPIC-Oxford and the median for AHS-2.|
1. Davey GK, Spencer EA, Appleby PN, Allen NE, Knox KH, Key TJ. EPIC-Oxford: lifestyle characteristics and nutrient intakes in a cohort of 33 883 meat-eaters and 31 546 non meat-eaters in the UK. Public Health Nutr. 2003 May;6(3):259-69.
3. Sobiecki JG, Appleby PN, Bradbury KE, Key TJ. High compliance with dietary recommendations in a cohort of meat eaters, fish eaters, vegetarians, and vegans: results from the European Prospective Investigation into Cancer and Nutrition-Oxford study. Nutr Res. 2016 May;36(5):464-77.