Cooking Fats: What You Need to Know About Oils, Butters, and Medication Interactions

When you reach for a bottle of cooking fats, fats used in food preparation, including oils, butter, and animal fats, that impact both flavor and health outcomes. Also known as dietary fats, they’re not just about taste—they can change how your body handles medication. Many people don’t realize that the type of fat you cook with can interfere with drugs you take daily. For example, grapefruit juice is a well-known culprit, but even olive oil or coconut oil can affect how your liver processes certain pills. This isn’t theoretical—it’s something people on blood pressure meds, cholesterol drugs, or thyroid treatments deal with every day.

vegetable oils, plant-derived fats like canola, soybean, and sunflower oil used in frying and baking are often promoted as heart-healthy, but they’re not always safe if you’re on statins or anticoagulants. Some oils contain compounds that slow down the enzymes your liver uses to break down meds, leading to dangerous buildup. On the flip side, butter, animal fat made from churned cream, commonly used in cooking and baking is high in saturated fat, which can raise cholesterol—but if you’re on warfarin, the vitamin K in butter can make your blood thinner less effective. Even olive oil, a monounsaturated fat from olives, often used in Mediterranean diets and as a supplement can interact with blood pressure drugs like valsartan, making your BP drop too low if you’re eating it heavily every day.

You don’t need to give up cooking fats. You just need to know which ones match your meds. If you’re on trimethoprim, for instance, your potassium levels could spike if you’re also eating lots of avocado or coconut oil. If you’re taking SSRIs, mixing them with high-fat meals might change how fast the drug hits your bloodstream. The same goes for people using hormone replacement therapy or SGLT2 inhibitors—fat intake affects absorption, hydration, and even how your body responds to side effects like dizziness or dehydration.

What you find below isn’t a list of recipes. It’s a collection of real stories and science-backed warnings about how everyday cooking choices connect to the pills you take. From how night shift workers accidentally mess up their meds because of late-night fried food, to why older adults on SSRIs need to watch their butter intake, these posts show the hidden links between your kitchen and your medicine cabinet. You’ll see what works, what doesn’t, and what you should avoid—even if it’s labeled "healthy."