You Are What You Eat – Netflix Documentary
Released in January 2025, Netflix’s documentary You Are What You Eat sparked wide discussion. It followed identical twins who changed their diets and lifestyles for eight weeks in a unique experiment designed to explore how food choices affect the body.
The programme was based on a peer-reviewed study exploring the Cardiometabolic Effects of Omnivorous vs. Vegan Diets in Identical Twins.
The Research Question
What are the cardiometabolic effects of a healthy vegan diet compared to a healthy omnivorous diet among identical twins during an 8-week intervention?
Why This Matters
Evidence continues to suggest that plant-based diets may provide cardiovascular benefits due to higher consumption of:
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Vegetables
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Legumes
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Fruits
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Whole grains
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Nuts and seeds
This trial set out to examine whether these benefits held up in a controlled, short-term intervention.
Study Design
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Type: Single-site, parallel-group, randomised clinical trial.
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Participants: Healthy adult identical twins.
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Groups: Vegan diet vs. Omnivorous diet.
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Duration: 8 weeks.
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Timeline: Enrolment from March–May 2022, final follow-up in July 2022.
Method
Phase 1 (Weeks 1–4): Participants received all meals via nationwide delivery, guided by health educator counselling.
Phase 2 (Weeks 5–8): Participants self-prepared meals following the same structured guidelines:
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Choose minimally processed foods.
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Build a balanced plate (vegetables, starch, protein, healthy fats).
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Maintain variety within each food group.
Data Collection:
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Three 24-hour dietary recalls at baseline, week 4, and week 8.
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Food intake logged with Cronometer.
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Clinical measures taken at each time point after fasting.
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Stool samples collected for future analysis of gut microbiome and inflammatory markers.
Results
Compared with their omnivorous twin, participants on a vegan diet experienced:
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LDL cholesterol reduction: –13.9 mg/dL
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Fasting insulin reduction: –2.9 μIU/mL
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Weight change: Greater loss (–1.9 kg vs. –0.29 kg)
No significant differences were observed between groups for triglycerides or HDL cholesterol.
Conclusion
The study found that a healthy vegan diet improved cardiometabolic outcomes compared with a healthy omnivorous diet over 8 weeks.
Why It’s Important
While the study was relatively small and short-term, it adds to evidence that diets rich in plant-based foods can improve cardiovascular health markers.
The documentary’s narrative strongly promoted vegan eating. Yet the wider question remains:
Our Question to Health Professionals
Does promoting a fully vegan narrative effectively encourage consumers to incorporate more plant-based foods — or can it backfire by alienating those who feel it’s “all or nothing”?
