Dec 27, 2014 04:19AM
By Julie Wendt, M.S.
As we consider how to include fat in our diet, oxidation is key. Simply put, oxidation is rust—meaning a breakdown of integrity and function. In your body, oxidation is a normal byproduct of eating, exercising and almost all physiological functions, which create unstable molecules that damage other molecules in their attempt to become stable. This happens inside our bodies and is at the root of the health recommendation to eat a diet rich in antioxidants.
Oxidation also happens to the fats that we eat. The process of cooking changes fat molecules and if we use fragile fats in our cooking, they oxidize into molecules that will cause damage once they are ingested. Therefore, cooking with stable fat and eating the more fragile fats when raw are important strategies for using dietary fat within a healthy diet.
What fats are good for cooking?
Saturated fats are the most stable due to their underlying structure—without double bonds that create kinks, the fat molecules stack neatly on top of each other and form a solid and strong compound. Examples of stable fats include ghee, coconut oil, palm, animal fats, avocado and olive oil. Why avocado and olive oil? Those are the only fats listed that are not primarily saturated fat. They are the exception to the rule. Their high antioxidant levels (polyphenols) help stabilize the fat molecules and mitigate the effects of heating.
Using high quality avocado and extra virgin oil is important so that you get the highest polyphenols possible. In addition, it is important to note that the fat profile of a conventionally raised animal is completely different (in an undesirable way) than an animal that has eaten grass. Therefore, it is important to choose your animal products wisely, and when possible, buy pasture-raised and finished animals since their omega 6:3 ratio will be closer to 1:1.
What fats are best used raw?
Unsaturated fats are best used raw, in particular the polyunsaturated fats (PUFA) found in vegetable oils such as flax, corn, walnut, peanut, sunflower, safflower, cottonseed and canola. The fragile chemical structure of these oils call for careful treatment including avoiding exposure to heat, light and oxygen. These oils should be stored in the refrigerator in a dark bottle and used within two to six months.
Monounsaturated fats such as olive, avocado, macademia, soy, and peanut can also have a high amount of omega 6 (inflammatory) fats and it is important to balance these fats with other fats high in omega 3 fats (salmon, flax).
As we wrap up this series on dietary fat, we return to our inquiry into the avocado and the doughnut. Hopefully it is clear that not only is a calorie not a calorie, but also the types of fat you choose can impact your health for better or for worse. Food is information that you are giving your body: choosing nutrient dense, anti-inflammatory and properly prepared fats will support optimal health.
How to make ghee (adapted from WellnessMama.com)
- Cut the butter into cubes and place in the saucepan.
- Heat the butter over medium heat until completely melted.
- Cook for about 10 to 15 minutes. It should first bubble, then foam, then bubble again before it is done. When you can no longer here the sizzling then it is done and the milk solids will be on the bottom of the pan. The ghee will have a roasted aroma and appear a deep golden color.
- Let cool slightly for 2 to 3 minutes and then slowly pour through the wire mesh strainer lined with several layers of cheesecloth.