Oils: How to choose 'em, how to use 'em

If you’re not already an oil whiz, and have oft wondered why everyone doesn't just pick up the big jug of olive oil that’s on sale and use it until it’s gone, read on.

There is so much to know about oils that this post will barely scratch the surface.  But since my readers are time-crunched people who like to cut to the chase, I’m going to attempt to remain firmly off my soap box and stick to the key takeaways.  There is even a bullet point summary at the end if you’re pressed for time.

3 things you need to know about your oil:

1. Fat type and ratio
2. Extraction method
3. Smoke point (for cooking)

1. Fat type.  Natural fats (oils) contain saturated, monounsaturated and polyunsaturated fat.  Side note of which you’re aware: trans fats (hydrogenated) are not from natural sources, and should not be part of your diet at all.

Saturated fats come primarily from animal sources, are associated with higher cholesterol and diabetes risk, and should exist in your diet in limited quantities.  These guys are typically solid at room temperature.  Think butter, shortening, pork fat.  Mono and polyunsaturated fats on the other hand are generally beneficial to your health, can actually improve cholesterol and lower diabetes risk, and therefore should be added to your diet with care.  These guys are typically liquid at room temperature (e.g. olive oil).

One of the most important kinds of polyunsaturated fats are Omega-3’s.  You’ve no doubt heard of these, and maybe you even take a fish oil supplement or better, you make sure to get your fill of salmon, sardines, flax, and walnuts.  They help just about every part of your body since they are an integral part of cell membranes, are linked to heart, brain, and eye health, and have shown promise in lupus, eczema, arthritis, and yes, even cancer.  Whew!  Quite a resume.  Omega-3’s are not made in our bodies, so we have to get them elsewhere.  That’s why they’re referred to as “essential” fatty acids.

Fat ratio.  Omega-6’s are also essential fatty acids, but you don’t see those supplements on the shelf at the health food store next to the Omega-3 supplements.  Why not?  Because these guys are WAY too present in the Standard American Diet (aka SAD).  According to this study, humans evolved on a diet with a 1:1 ratio of Omega-6 to Omega-3 fatty acids, whereas today’s Western diet is around 16:1.  Excessive Omega-6 fatty acids basically undo all the benefits aforementioned on Omega-3’s.  These are found in refined vegetable oils that land in tons of processed foods (think snacks, cookies, and crackers), and in fast food.  So the key is to find fats with a good ratio of Omega-6 to Omega-3 fatty acids.

2. Extraction method.  You might have heard the terms “cold-pressed” or “expeller-pressed.”  If you don’t see one of those phrases on your cooking oil, by the way, you probably shouldn't buy it.  Those terms indicate that the oil has been mechanically extracted from the seed rather than chemically extracted.  Many of the oils you see on the shelf at the grocery store are extracted using a chemical like hexane gas.  When that’s the case, they then go through even more refinement to make sure the hexane itself gets removed.  Needless to say, these will be much less flavorful, not to mention nutritionally deficient at best.  Do your body a favor: pay the extra few bucks, and look for cold pressed or expeller pressed oils.  Also, since I can’t get through most posts without saying it, go for organic if you can find it.  Canola is one of the most genetically modified crops, so if you’re not buying organic canola oil, you’re almost certainly getting GMO’s with your stir fry.  Olive oil is also easy to find organic.  Organic grapeseed oil is hard to find, mostly because it’s incredibly hard to get the oil out of the tiny grapeseed without using the hexane, though you can find brands that do not use hexane even though they aren’t organic – that’s what I look for.

3. Smoke point.  Here’s the important part most people don’t consider.  Some oils are better for cooking than others due to their smoke point.  My Italian relatives would cringe to hear me say so, but cooking everything in olive oil is not the way to go.  It has a low smoke point, so if you’re stir frying in olive oil, you’re likely killing the phytonutrients you would’ve gotten from the oil had you drizzled it on salad.  Worse, the decomposition process can create oxygen radicals, which are linked to cancer.  So it’s important to note the smoke point and cook accordingly.  See table below for smoke points of commonly used oils.

In summary:

• Unless you’re a serious chef, you can probably get by with 3 kinds of oil in your kitchen: olive, canola, and grapeseed.
• Use organic extra virgin cold- or expeller-pressed olive oil for drizzling, not cooking.
• Use organic cold- or expeller-pressed canola or cold- or expeller-pressed grapeseed oils for cooking and sautéing.
• Use organic coconut oil in place of butter (yes, it’s high in saturated fat, but also good for heart health, immune system, skin and metabolism, among other things!)
• Use organic flax oil in your smoothies or drizzled on salad, but never heat it.
• Use other organic, cold- or expeller-pressed oils with decent omega 6-3 ratios in moderation (e.g. peanut, sesame, walnut).
• Try to limit all other oil intake (e.g. corn, cottonseed, sunflower, palm), and remember, they aren't just in a bottle on the shelf.  In fact, they’re mostly NOT there.  They’re in chips, dried fruit, peanut butter and lots of other places.  Read the label!

Here is a nice summary on smoke points and uses from PCC Natural Markets: 

Oil	Raw	Low heat	Med. heat	Med. High heat	Very	Characteristics and uses
					high heat
Low heat = 275º to 325º F • Medium heat = 325º to 350º F • Medium-high heat = 350º to 400º F • Very high heat = 400º to 495º F
Avocado (expeller-pressed), refined	X	X	X	X	X	Lovely texture, wonderful for searing meat, whipped potatoes and stir-fries. Smoke point 450º F.
Avocado (cold-pressed), unrefined	X	X	X	X	X	Lovely texture, wonderful for searing meat, whipped potatoes and stir-fries. Smoke point 500º F.
Canola (medium-high heat), refined	X	X	X	X		Neutral flavor, all-purpose, good for baking.
						Smoke point 425º F. May be genetically modified if not organic.
Canola, unrefined	X	X				Mild flavor, may be genetically modified if not organic.
Coconut (virgin/extra virgin), unrefined		X	X			Lovely for cakes, pie crusts, light sautéing.
						Cholesterol-free. Smoke point 280º to 350º F.
Grapeseed (expeller-pressed), refined	X	X	X	X	X	Clean, neutral taste. Smoke point 485º F.
Olive (extra virgin), unrefined	X	X				Ideal for salads, raw foods, pesto and dipping bread. Smoke point 325º F.
Peanut (expeller-pressed,	X	X	X	X		Adds flavor to lightly cooked foods and cold dishes. Smoke point 212º to 400º F. Potential allergen.
Safflower (high heat), refined	X	X	X	X	X	Mild flavor for high-heat cooking. Smoke point 450º F.
Safflower, unrefined	X					Delicate flavor.
Sesame, refined	X	X	X	X	X	Adds smoky flavor to seared meats, stir-fries.
						Smoke point 445º F.
Sesame, unrefined (including toasted)	X					Aromatic, nutty, best in dressings and sauces.
Sunflower (high oleic), refined	X	X	X	X	X	Nearly neutral flavor. Smoke point 450º F.
Sunflower (expeller-pressed), refined	X	X	X	X	X	Multi-purpose. Smoke point 460º F.
Sunflower (cold-pressed), unrefined	X					Rich flavor, best in cold dishes.
Walnut, refined	X	X	X	X		Adds character to salads, marinades and sautés. Smoke point 400º F. Potential allergen.