Healthy Oils: Which Shouldn’t Be Heated and Why

In the quest for a healthy diet, choosing the right oils is crucial. However, not all oils are created equal when it comes to cooking. Some oils, when exposed to high heat, lose their health benefits or even become detrimental to your health. Let's explore which oils should be used cold and which can be heated, backed by scientific facts and expert advice.

Unrefined Oils: Best Kept Cold

Unrefined oils, such as flaxseed oil, wheat germ oil, and walnut oil, are known for their unique flavors and health benefits. However, these oils have a low smoke point, which means they start to break down and produce harmful compounds when exposed to heat. Therefore, they are best used unheated in recipes or as dressings.

Flaxseed Oil and Its Limitations

Flaxseed oil is celebrated for its rich content of omega-3 fatty acids, but this very property makes it susceptible to damage when exposed to heat. As Dr. Joseph Mercola reported in a 2010 interview with Dr. Rudi Moerck, unrefined flaxseed oil should never be used for cooking as it will undergo oxidative damage, leading to accelerated decomposition and a shortened shelf life.

Wheat Germ Oil and Oxidative Stress

Similar to flaxseed oil, wheat germ oil also has a low smoke point and should be stored and used cold. This oil is rich in antioxidants and vitamin E, but heating can reduce its beneficial properties and introduce harmful compounds. Dr. Mercola advises purchasing wheat germ oil in small quantities to ensure it is consumed before it goes rancid.

Walnut Oil: A Gentle Friend to the Plate

Walnut oil, with its distinctive nutty flavor, is another unrefined oil that should be used minimally heated. It is rich in omega-3 fatty acids, but these same fatty acids make it delicate when exposed to heat. Dr. Mercola notes that walnut oil should only be drizzled over cold dishes to preserve its health benefits.

Extra-Virgin Olive Oil: A Cold Companion

Extra-virgin olive oil is a staple in many healthy diets, particularly the Mediterranean diet, due to its high content of monounsaturated fats. While it is a great addition to salads and cold dishes, olive oil is not suitable for cooking, especially when it comes to extra-virgin varieties. Sautéing or frying olive oil significantly reduces its nutritional value and health benefits.

Chlorophyll and Rancidity

Dr. Mercola explains that extra-virgin olive oil contains chlorophyll, a pigment that accelerates decomposition and accelerates rancidity. This means that even stored in ideal conditions, extra-virgin olive oil will quickly become unpalatable and potentially harmful if used in cooking. Dr. Mercola recommends buying small bottles to ensure the oil is consumed within a few months of opening.

Alternative Cooking Oils: Protectors Against Heat

For those who need oils for cooking, there are several options that can withstand higher temperatures without compromising on health benefits. Coconut oil, organic butter, ghee, and unfiltered avocado oil are all excellent choices. Each of these oils has a high smoke point, allowing them to be used in cooking without losing their beneficial properties.

Avocado Oil: A Sensitive Oil

Unfiltered avocado oil, despite its high smoke point, is sensitive to temperature changes. It must be kept refrigerated to prevent it from solidifying, which requires planning in advance. Once removed from the refrigerator, it can take about 15 to 20 minutes to return to a liquid state. This makes it a bit more inconvenient than other cooking oils, but its health benefits justify the slight extra effort.

MCT Oil: A Cooking Neutral

MCT (medium-chain triglycerides) oil is another option for those who need to cook. Despite some conflicting information about its cooking properties, Dr. Mercola advises against using it for high-heat cooking. Instead, he suggests incorporating it into smoothies or other cold recipes.

Conclusion

In conclusion, the choice of oil for cooking is not just about flavor but also about health. Unrefined oils like flaxseed, wheat germ, and walnut oil should be used cold. Olive oil, despite its health benefits, should be reserved for drizzling on dishes rather than cooking. Cooks who enjoy high-heat cooking should opt for oils that can withstand the process, such as coconut oil, organic butter, ghee, or avocado oil. By making informed choices, you can ensure that your cooking enhances your health rather than poses a risk.