Not All Fats Are Created Equal: Here’s What I Tell My Patients

Introduction

For years, patients have come to me asking if they should avoid fat altogether. The answer? Absolutely not. Fat is essential — for your brain, hormones, and even your heart. But the kind of fat matters tremendously. In this article, I'll walk you through the different types of fats, how they affect your health, and which ones to prioritize in your diet.

What Are the Main Types of Fat?

There are four main types of dietary fat:

• Saturated fats
• Trans fats
• Monounsaturated fats
• Polyunsaturated fats

Each of these affects your body differently. Understanding the science behind them helps you make smarter choices.

Are All Saturated Fats Bad?

Not necessarily. Saturated fat is found in foods like red meat, butter, and full-fat dairy. While excessive intake has been linked to heart disease, newer research suggests that the type and source of saturated fat matter. Whole-food sources like coconut and grass-fed dairy may not have the same risks as processed meat or baked goods.

What Are Trans Fats and Why Should You Avoid Them?

Trans fats are artificially produced through a process called hydrogenation. They're found in some margarines, fried foods, and baked goods. Trans fats raise LDL (bad cholesterol) and lower HDL (good cholesterol), increasing your risk of heart disease and inflammation. Most countries have restricted or banned them for this reason.

What Are Healthy Fats?

Healthy fats are primarily unsaturated:

• Monounsaturated fats — found in olive oil, avocados, nuts
• Polyunsaturated fats — found in flaxseed, walnuts, chia seeds, and fatty fish

These fats support heart health, reduce inflammation, and help absorb fat-soluble vitamins like A, D, E, and K.

How Do Fats Affect Your Hormones?

Fats are crucial for hormone production. Cholesterol, which is often vilified, is actually the building block for estrogen, testosterone, and cortisol. Low-fat diets can disrupt hormonal balance, affect menstrual cycles, and impair mood regulation.

Can Fat Help With Weight Loss?

Surprisingly, yes. Fat is satiating — meaning it keeps you full longer. Including healthy fats in meals reduces cravings and stabilizes blood sugar, which can help with weight management. Diets that include adequate fat often outperform low-fat diets over time in maintaining weight loss.

Which Fats Are Best for Cooking?

Stability at high heat matters:

• High-heat cooking: Use avocado oil, ghee, or coconut oil
• Low-heat or dressings: Use extra virgin olive oil or flaxseed oil

Oils like flaxseed or walnut oil should never be heated as they oxidize quickly and lose their benefits.

Is Cholesterol in Food Still a Concern?

Dietary cholesterol doesn’t affect blood cholesterol as much as once believed. Most of your cholesterol is made by your liver. The focus now is on reducing oxidized cholesterol and inflammation from poor-quality fats and sugars, not simply avoiding eggs or shrimp.

What About Omega-3 vs. Omega-6?

Omega-3 fats (found in salmon, flax, walnuts) are anti-inflammatory. Omega-6 fats (in vegetable oils like corn and soybean) are essential too — but the modern diet often contains far too much omega-6 and too little omega-3. This imbalance can drive inflammation and chronic disease. Aim to increase omega-3 intake and reduce processed omega-6 oils.

Can Healthy Fats Help with Skin and Brain Health?

Absolutely. Omega-3s support cognitive function, mood, and reduce risk of neurodegenerative diseases. Fats also support skin elasticity, hydration, and barrier function. Many skin issues improve when essential fatty acids are restored in the diet.

Is There a 'Perfect' Fat Ratio?

There's no one-size-fits-all, but a balanced intake of monounsaturated and omega-3 polyunsaturated fats is ideal. Keep saturated fat in moderation, avoid trans fats entirely, and limit refined omega-6 oils.

How Can You Make Better Fat Choices?

Use this simple guide:

• Use olive oil instead of canola or soybean oil
• Add avocado to sandwiches and salads
• Snack on walnuts or almonds instead of chips
• Cook with ghee or avocado oil instead of margarine
• Eat fatty fish (like salmon or sardines) twice a week

Can Fat Affect Insulin Resistance?

Yes. While carbs play a major role in blood sugar regulation, the type of fat consumed also matters. Saturated and trans fats are linked to worsened insulin sensitivity, while unsaturated fats may improve it. This is especially relevant for those with PCOS, prediabetes, or metabolic syndrome.

What About Fat in a Plant-Based Diet?

Plant-based eaters need to be intentional about including fats from nuts, seeds, avocado, and oils. These fats help absorb fat-soluble vitamins often found in vegetables and prevent deficiencies in strict vegan diets.

Are Low-Fat Diets a Good Idea?

Not usually. Low-fat diets often lead to increased consumption of processed carbs, which can spike blood sugar and increase triglycerides. For most people, moderate healthy fat intake paired with fiber-rich carbs and lean protein is the best approach.

Final Thoughts

Fat is not your enemy — but it's important to choose it wisely. Understanding the difference between harmful and helpful fats can dramatically shift your long-term health. Focus on whole-food sources, balance your intake, and don't fear fat — embrace the right kinds.

In my clinical experience, patients who shift from low-fat processed diets to balanced whole-food fat sources often report better energy, skin, mood, and appetite regulation. Fat is fuel, structure, and hormone support — it deserves a place on your plate every day.