Extra virgin olive oil is the most-evidence-backed cooking fat in nutrition research. The challenge: olive oil oxidises over time, losing benefits and flavour. Buying smaller bottles more frequently keeps it fresh.
What to buy
Extra virgin (cold-pressed). From single country or region (not blend of multiple sources). Dark green glass bottle (protects from light). Use-by within 12 months of purchase. £8-25 for genuinely good UK options.
How to use
Daily — drizzled on salads, used for cooking at moderate heat, finishing dishes. Don't deep-fry (too expensive and high heat degrades it). Vinaigrettes, roasted vegetables, finishing pasta.
Replacing other cooking oils with olive oil is one of the easiest evidence-based dietary upgrades.