What Drives Plant-Based Food Intentions? A Study of Two Theories

This study looked at what predicts a person's intention to choose plant-based foods. Researchers surveyed 454 North American adults to compare two psychological theories.

🔬 What the study did

Researchers used an online survey to measure participants' intentions to change their diet toward plant-based foods. They compared two theories: the theory of planned behavior and the newer theory of behavioral choice. The survey included questions about attitudes, social norms, habits, and sense of obligation.

📈 What it found

• The older theory explained 65% of the differences in people's intentions.
• The newer theory explained 80% of the differences—a significantly larger amount.
• The strongest predictors were sense of obligation, attitude-values-affect, and habit.
• Social norms from the older theory also played a role.
• Five small interactions between factors also contributed to intentions.

⚖️ Study vs. claim

The study measured what predicts intentions to choose plant-based foods. It did not test whether these intentions lead to actual dietary changes or health outcomes.

🚫 What it does NOT show

• It does not show that people actually changed their diet.
• It does not show cause and effect—only associations.
• It does not apply to non-North American populations.
• It does not measure health or longevity outcomes.

📊 Evidence level

An observational study in people.

🎯 Confidence indicator

Confidence: Low to moderate — based on a single survey with self-reported intentions.

🔍 How much to trust it

Trust tier: Moderate. This is an observational human study — it shows association, not proof of cause. The results are informative but not definitive.

This survey shows that personal obligation and attitudes strongly predict plant-based food intentions, but actual behavior was not measured.

⚠️ Limitations

• Self-reported intentions, not actual behavior.
• Cross-sectional design—no follow-up over time.
• Single survey of 454 adults.
• Only North American participants.

❓ Open questions

• Do these intentions lead to real dietary changes?
• Would the same predictors apply in other cultures?
• How do these intentions relate to long-term health?

📋 Your action plan

• ✅ Understand that intentions are not the same as actions.
• ✅ If you want to eat more plant-based foods, consider your own sense of obligation and attitudes.
• ✅ Talk to a dietitian or doctor before making big dietary changes.
• ✅ Look for studies that measure actual behavior, not just intentions.

📄 Source

Applying the theory of behavioral choice to plant-based dietary intentions. Appetite. 2024 PubMed