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The Real Story on Saturated Fat

February 2, 2026

¹For years, you were told to avoid saturated fat—that it’s “bad” for you.

But the reality? Research hasn’t ever proved that out.

The advice was based on the premise that foods higher in saturated fat raise LDL cholesterol—a risk factor for heart disease.

Only it’s not so straightforward. Not even close. I’ll show you what really matters—and how to know if you’re eating in a way that’s best for your health.

The Truth about Saturated Fat

When it comes to saturated fat and your health, here’s what most people have never been told: The source of that saturated fat really matters.^¹,²

For example, if someone’s diet is high in sugar and refined starches, they shouldn’t eat much saturated fat. (More importantly, they should change their diet!)

But if someone’s eating mostly whole foods—and keeping sugar and refined starches low—they often don’t need to worry about the saturated fat that naturally comes with those foods.

To be sure, that’s not true for every single person—there’s a large genetic variation in how people respond to saturated fat.

That’s why I tell people not to just assume. Instead, test and track your full cholesterol and heart panel when you make any diet changes. (More on what markers you should track in a moment.)

Why the Kinds of Food You Eat Matters

Saturated fat itself isn’t a food.

It’s one component of certain foods—mostly animal foods.

When you eat saturated fat from whole foods, you’re eating foods like meat, dairy, and eggs—not fat by itself.

Those foods also contain high-quality protein, essential micronutrients, and other healthy fats.

When saturated fat comes from highly-processed foods, it’s packaged very differently.

These products typically combine saturated fat with refined starch and/or added sugars—often in amounts you’d never find in nature.

Think chips, cookies, ice cream, fast food, and packaged snack foods.

This combination drives bigger blood sugar spikes, which can increase inflammation and negatively affect metabolic health. It also helps make them hyper-palatable—so they’re easy to overeat and, as a result, more likely to cause weight gain.

All these factors can send cholesterol levels soaring, but saturated fat alone isn’t necessarily to blame.

All Saturated Fat Isn’t the Same

What’s more, there are many types of saturated fatty acids, and even whole foods can offer different mixes from each other.

For example, coconut has a very different saturated fat profile than beef, and dairy has a different profile than both.

Some saturated fatty acids impact LDL cholesterol more than others. Stearic acid—found in foods like cocoa and some meats—usually doesn’t affect LDL cholesterol much, if at all.

And emerging research even suggests one type of saturated fat—pentadecanoic acid—may help support healthy aging at the cellular level. (I make a point to add it specifically to my diet, through the supplement Fatty 15.)

Further, research shows that replacing saturated fat with added sugar and refined starch doesn’t improve heart disease risk—and can actually make it worse.¹

This is what can happen when people cut out full-fat foods—but swap in “low-fat” processed foods that are higher in added sugar and refined starch.

Here’s Another Important Point

Most of the time, foods aren’t eaten in isolation—they’re eaten as part of meals.

So the effect of saturated fat depends on the entire meal—not just the food it comes from.

Consider this comparison:

Steak + broccoli + brown rice…

Versus… steak + fries + soda.

Same saturated fat. Very different health implications. This is especially true if it represents how you consistently eat (which is the most important consideration).

The Big Takeaways

Yes, saturated fat can raise LDL cholesterol—but it depends on factors like:

the source of the saturated fat (whole foods vs highly-processed foods)
what the rest of your diet looks like (lots of added sugar and refined starch… or lots of fiber-rich plant foods?)
total calorie intake (are you overeating or not?)

Plus, it can vary from person to person.

Your baseline metabolic health matters. For example, when people who have obesity and are metabolically unhealthy consume a very-low carb diet that’s high in fat (including saturated fat), they often see improvements in their LDL cholesterol and other heart disease risk factors.

But people who are lean and metabolically healthy may not respond as well to the same diet.

Genetics also play a big role. Some people do well on higher saturated fat intake, while others see worse lipid responses.

That’s why the future is “precision nutrition”—where recommendations are personalized based on your genetics and real-world lab markers, not one-size-fits-all rules.

Don’t Just Hope for the Best

One final note: When it comes to your diet, saturated fat, and heart disease risk, it’s not enough to look at “LDL cholesterol” alone.

It’s essential to track your full lipid and metabolic profile, including:

Apolipoprotein B (ApoB): an estimate of how many “atherogenic” particles you have—these are particles that can penetrate your artery wall and contribute to plaque.
LDL particle number: a direct count of how many LDL particles are circulating in your blood stream. In general, a higher number means more particles that can enter the artery wall over time.
LDL particle size: whether your LDL is mostly Pattern A (larger, more buoyant particles) or Pattern B (smaller, denser particles). Pattern B is associated with higher cardiovascular risk.
Lipoprotein(a): a largely inherited LDL-like particle that can raise cardiovascular risk, even if your other numbers look good.
High-sensitivity C-reactive protein (hs-CRP): a marker of inflammation.
Fasting glucose: your baseline blood sugar level (normally after an 8-12 hour fast).
Hemoglobin A1c (HbA1c): your average blood sugar over the past 2–3 months.
Fasting insulin (or another insulin-resistance marker): shows how much insulin your body is producing to keep blood sugar in range.

We’re all different, and this is how you see what’s actually happening in your body. (You can test all of this through Function Health .) It can help you determine whether your diet choices are helping—or hurting—your health.