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Fats & Oils

Table of Contents

Why dietary fats matter
Types of dietary fats
The omega-6 to omega-3 ratio
Cooking with different oils

Why dietary fats matter

Fats are essential for hormone production, brain function, and absorbing vitamins A, D, E, and K ^[1]. Your brain is 60% fat. Cell membranes need fat for structure. Without adequate fat intake, you cannot make steroid hormones like testosterone and estrogen.

Types of dietary fats

Healthy fats to prioritize

Monounsaturated fats: Found in olive oil, avocados, and nuts. These fats improve cholesterol levels and reduce inflammation ^[1]. Extra virgin olive oil is particularly rich in polyphenols, plant compounds with antioxidant properties.

Omega-3 fatty acids: Found in fatty fish (salmon, sardines, mackerel), walnuts, and flaxseeds. Omega-3s reduce inflammation, support brain health, and lower triglycerides ^[2]. The two key types are EPA and DHA from fish, and ALA from plants.

Fats to limit

Industrial trans fats: Found in partially hydrogenated oils and many processed foods. Trans fats raise LDL (bad) cholesterol and lower HDL (good) cholesterol ^[3]. Many countries have banned them, but they still appear in some baked goods and fried foods.

Highly processed seed oils: Oils like soybean, corn, and sunflower are high in omega-6 fatty acids. While omega-6 is essential, the typical Western diet contains far too much, creating an imbalance that promotes inflammation ^[3].

The omega-6 to omega-3 ratio

Humans evolved eating roughly equal amounts of omega-6 and omega-3. Modern diets contain 15-20 times more omega-6 ^[2]. This imbalance drives chronic inflammation, which contributes to heart disease, diabetes, and autoimmune conditions. To improve your ratio: eat more fatty fish, use olive oil instead of seed oils, and reduce processed food consumption.

Cooking with different oils

Each oil has a smoke point—the temperature where it starts breaking down and producing harmful compounds. For high heat (above 200°C/400°F), use avocado oil or ghee. For medium heat, olive oil works well. For dressings and finishing dishes, extra virgin olive oil provides the most flavor and polyphenols ^[1].

References

Choose extra virgin for cold use

Extra virgin olive oil contains the most polyphenols, but these degrade with heat. Use it for dressings and finishing dishes. For cooking, regular olive oil or avocado oil works better.

Eat fatty fish twice weekly

EPA and DHA omega-3s maintain neuronal membrane fluidity and reduce neuroinflammation. Salmon, mackerel, and sardines provide the most bioavailable forms.

pubmed.ncbi.nlm.nih.gov

Balance your omega ratio

Reduce omega-6 by avoiding processed foods and industrial seed oils. Increase omega-3 by eating fatty fish, walnuts, and flaxseeds. Aim for a ratio closer to 4:1 or better rather than the typical 15:1.

Match oil to cooking temperature

For high heat (above 200°C/400°F), use avocado oil or ghee. For medium heat, olive oil works well. Never heat flaxseed oil or walnut oil—these are for cold use only.

Read labels for hidden trans fats

Check ingredient lists for 'partially hydrogenated oils'—this indicates trans fats even if the label claims zero grams. These oils appear in crackers, baked goods, and margarine.

What is the difference between saturated and unsaturated fat?

Saturated fats have no double bonds between carbon atoms and are solid at room temperature (butter, coconut oil). Unsaturated fats have one or more double bonds and are liquid at room temperature (olive oil, fish oil). Saturated fats were once thought to cause heart disease, but recent evidence shows this link is weaker than believed. Moderate saturated fat intake from whole foods is generally fine for most people.

Is coconut oil healthy or not?

Coconut oil is 90% saturated fat, which made it controversial. However, about half is lauric acid, a medium-chain fatty acid that raises HDL (good) cholesterol. While coconut oil is not a miracle food, using it in moderation is reasonable. It's stable for cooking and may have modest metabolic benefits. Like any fat, it is calorie-dense, so portions matter.

What are omega-3 fatty acids and why do I need them?

Omega-3s are essential fats your body cannot make. EPA and DHA from fish reduce inflammation, support brain function, and lower heart disease risk. ALA from plants (flax, walnuts) must convert to EPA/DHA, but humans convert only 5-10%. For optimal health, eat fatty fish twice weekly or consider algae-based supplements if you don't eat fish.

Why is the omega-6 to omega-3 ratio important?

Both omega-6 and omega-3 are essential, but they compete for the same enzymes in your body. Omega-6 tends to promote inflammation while omega-3 reduces it. Humans evolved with roughly equal amounts (1:1 ratio). Modern diets contain 15-20 times more omega-6, creating chronic low-grade inflammation. Improve your ratio by reducing processed foods and seed oils while increasing fish, walnuts, and flax.