What fats should I cook with?
Use oils and fats that fit the cooking method, taste, budget, and calorie target. For most everyday cooking, olive oil, extra-virgin olive oil, avocado oil, canola oil, and other mostly unsaturated oils are reasonable defaults. Butter, ghee, tallow, lard, and coconut oil can be used for taste and specific dishes, but they are higher in saturated fat, so portions and health markers matter.
Smoke point is relevant, but it is not the whole story. Heat stability also depends on fatty-acid composition, antioxidants, refinement, storage, cooking time, oxygen exposure, moisture, and whether the oil is reused. Extra-virgin olive oil is often more heat-stable than people assume because it is rich in monounsaturated fat and protective minor compounds, though high heat can still change its flavor and reduce some delicate compounds.
For normal sauteing, roasting, eggs, vegetables, meats, and mixed dishes, olive oil or avocado oil are easy defaults. For very high-heat searing, a refined avocado oil, refined olive oil, canola oil, or another neutral high-heat oil may be more practical. For finishing, dressings, and flavor, extra-virgin olive oil, sesame oil, butter, or other flavorful fats can make sense because the taste is the point.
The bigger cooking-fat issue is often quantity. One tablespoon of oil is roughly 120 calories. A generous pour can turn a lean meal into a high-calorie meal without changing food volume very much. If fat loss is the goal, measure oil, use a spray, or build meals with lower-fat cooking methods when precision matters. If muscle gain is the goal and appetite is low, adding oil can be a useful way to raise calories without much food volume.
Avoid repeatedly overheating and reusing the same oil, especially for deep frying. Deep-fat frying changes oils through oxidation, hydrolysis, and polymerization, and those changes depend on temperature, time, food moisture, oil type, antioxidants, and reuse. Occasional home cooking with reasonable oils is a different context from repeatedly reused fryer oil.
A simple home setup works well: extra-virgin olive oil for most cooking and finishing, avocado or refined olive oil for higher heat, a neutral oil when flavor matters, and butter or coconut oil when you specifically want that taste. The "best" cooking fat is not just the one with the highest smoke point. It is the one that supports flavor, stability, calories, and the overall diet.