从黄油到橄榄油：膳食脂肪红绿灯，关键看来源与频率

October 21, 2026

For decades, fat was one of nutrition’s most demonized nutrients. The prevailing wisdom was simple: If you wanted to lose body fat and protect your cardiovascular health, the less fat you ate, the better. And although we now know that nutrition is considerably more complicated, some of those old assumptions have proved surprisingly difficult to shake.

Just ask nutritionist Laura Parada, author of What Drives Us to Eat This Way. She often sees an old school, anti-fat mentality among her clients, particularly women, who instinctively reach for anything labeled 0%, skim, or low-fat under the assumption that it’s the obvious, healthier choice.

But as Parada points out, “Eating fat doesn’t mean accumulating body fat, nor does eliminating it from our diet automatically make a diet better.”

In fact, fat is essential to our health. “Some fatty acids are essential; they form part of our cell membranes, play a role in various physiological processes, and allow us to absorb fat-soluble vitamins such as A, D, E, and K,” Parada explains. “In addition, the presence of fat in meals can contribute to feelings of fullness and make our meals more satisfying.”

For women, there’s another important consideration: hormonal health. “Lipids and cholesterol are involved in processes related to the synthesis of steroid hormones, including sex hormones,” says Parada. “This doesn’t mean that eating more fat will produce more hormones, but excessively restricting fat isn’t necessarily a good strategy either—especially when caloric intake is insufficient to meet the body’s needs.”

Which brings us to a more useful question. Rather than asking How much fat should I eat?, Parada suggests asking What sources of fat am I choosing, and what role do they play in my diet? After all, not all fats—or the foods that contain them—are created equal. The source, nutritional profile, degree of processing, and frequency with which we consume them all matter, as does our overall eating pattern.

To make sense of it all, Parada and dietitian María Casas helped us sort common sources of dietary fat into a traffic-light system: red for those best limited, orange and yellow for those worth approaching with a little more nuance, and green for the healthy fats to prioritize.

Red: The Least Healthy Sources of Fat

Industrial baked goods, ultra-processed snacks, certain fried foods, and processed meats.

The foods in this category probably won’t come as a surprise. Industrially-produced baked goods, certain ultra-processed snacks, fried foods, and processed meats such as sausages and bacon tend to combine less favorable fat profiles with other ingredients best consumed in moderation.

“These foods are designed to be extremely flavorful; they provide a lot of calories in a small volume and are very easy to consume in excess,” explains Casas. “To achieve that palatability, they’re often packed with fats and refined flours, added sugars, salt…”

But there’s one type of fat that deserves particular attention: industrially produced trans fats, historically found in partially hydrogenated oils and certain margarines. “This is the area where we can be most emphatic: It’s important to keep consumption as low as possible due to their adverse effects on lipid profiles and cardiovascular risk,” says Parada.

Fortunately, industrial trans fats have been largely eliminated from the food supply in many countries through regulation, although they haven’t disappeared everywhere. And anyway, Parada is quick to emphasize that the occasional indulgence isn’t a nutritional catastrophe: “No single food makes us healthy, nor does any single food ruin our diet. In nutrition, what matters is the amount, the frequency, the context, and what we do most of the time.”

Orange: Fats Best Enjoyed in Moderation

Butter, coconut oil, and some full-fat dairy products, particularly aged cheeses.

Butter lands in the orange category—not because it’s inherently terrible, but because its fatty-acid profile is less favorable than those of the foods further down in our ranking. The same goes for coconut oil and certain full-fat dairy products, including aged cheeses, which can contain substantial amounts of saturated fat.

But before you banish butter from your kitchen, Parada has an important clarification. “Being in the orange category doesn’t mean these are ‘bad’ foods or that we have to eliminate them from our diets; what matters is the amount, the frequency, and which sources of fat dominate our daily lives.”

Butter is a useful example. Although high-quality butter or butter from grass-fed cows may differ somewhat in composition, it remains predominantly a source of saturated fat. And coconut oil? Its natural origins don’t automatically make it a nutritional superstar.

“Just because a food is natural doesn’t necessarily mean we should make it our primary source of fat,” Parada explains. “It can be included as part of a varied diet, but for regular consumption, I’d still prioritize other sources.” In other words, there’s room for butter on your toast. It just shouldn’t to be your go-to cooking fat.

Yellow: The Nutritional Middle Ground

Eggs, some cheeses, unprocessed meats, dark chocolate, plain whole-milk yogurt, and certain types of fish.

This is where things get interesting—and where the limitations of ranking foods solely by their fat content become especially apparent. The yellow category includes eggs, certain cheeses, unprocessed meats, plain whole-milk yogurt, dark chocolate, and some types of fish. These aren’t necessarily unhealthy foods. Many can be valuable components of a balanced diet, including the Mediterranean diet. But as sources of fat, they don’t all offer the same advantages as the foods in the green category.

Take eggs, for example. For decades, they were demonized because of their cholesterol content. Today, however, we understand that the relationship between dietary cholesterol and blood cholesterol levels is considerably more complex than once believed. Most experts now agree that eggs are nutritionally valuable foods that can absolutely have a place in a healthy diet.

The same nuance applies to yogurt and cheese. Although some varieties contain substantial amounts of saturated fat, they don’t necessarily affect the body in the same way as butter or cream.

This is where the concept of the food matrix comes into play. Rather than consuming nutrients in isolation, we eat them as part of complex foods whose structure and combination of nutrients can influence how our bodies respond. The distinction is particularly relevant to fermented dairy products—such as yogurt, kefir, and certain cheeses—which may have different effects on cardiovascular health than their saturated-fat content alone would suggest.

And then there’s dark chocolate. While cocoa contains beneficial flavanols, Casas notes that dark chocolate is also relatively high in saturated fat and calorie-dense. For that reason, she argues, the evidence doesn’t justify putting it on quite the same nutritional pedestal as extra virgin olive oil, nuts, or seeds. Remember: a food’s fat content tells us something about its nutritional value, but rarely paints the whole picture.

Green: The Healthiest Sources of Fat

Extra virgin olive oil, nuts, seeds, olives, avocados, and fatty fish.

And now, the winners. At the top of the ranking are foods rich in unsaturated fatty acids, including extra-virgin olive oil, nuts, seeds, olives, avocados, and fatty fish.

The undisputed star, according to Casas, is extra virgin olive oil. “It represents the exact opposite of what we’ve seen in the worst-ranked groups: It’s a source of fat rich in unsaturated fatty acids that, when it replaces sources high in saturated fat, consistently yields favorable results for cardiovascular health.”

It’s also a cornerstone of the Mediterranean diet, one of the most extensively studied dietary patterns for cardiovascular health. “The Mediterranean diet is one of the dietary patterns with the strongest evidence for cardiovascular disease prevention, including evidence from clinical trials in populations at cardiovascular risk,” explains Parada. “Extra virgin olive oil would be my first choice for both dressing salads and cooking.”

But olive oil is hardly alone in its nutritional virtues. Nuts and seeds provide unsaturated fats along with fiber, plant-based protein, vitamins, minerals, and other beneficial compounds. Avocados are rich in predominantly monounsaturated fats, while also providing fiber and important micronutrients.

And fatty fish, such as salmon, sardines, and mackerel, earn their place thanks in large part to their long-chain omega-3 fatty acids, particularly EPA and DHA. What these foods have in common isn’t simply that they contain fat. It’s that they offer favorable fatty-acid profiles alongside other nutrients that contribute to overall health.

The Top Three Sources of Healthy Fat

If our little traffic-light system has you wondering which foods deserve the most space in your shopping cart—and in your belly—Casas has narrowed the green category down to three particular favorites.

Bronze Medal: Olives and Avocados

“These are whole plant foods, rich in unsaturated fats, with high nutritional density, and associated with excellent long-term health outcomes,” she says. Both provide predominantly monounsaturated fats, making them versatile additions to everything from salads and grain bowls to toast.

Silver Medal: Flaxseeds

“They contain more omega-3s than virtually any other plant-based food commonly consumed,” says Casas, who also praises their affordability. Flaxseeds are particularly rich in alpha-linolenic acid (ALA), a plant-based omega-3 fatty acid. A tablespoon of ground flaxseed can make a meaningful contribution toward daily ALA needs, while also providing fiber.

Sprinkle them over yogurt or oatmeal, blend them into smoothies, or add them to baked goods. Grinding flaxseeds also makes their nutrients easier to access.

Gold Medal: Raw or Roasted Nuts

And taking the top spot: nuts. “Nuts consistently improve many of the markers known to be involved in the development of cardiovascular disease, including LDL cholesterol, ApoB, the overall lipid profile, and other cardiometabolic risk factors,” says Casas.

Walnuts, almonds, pistachios, hazelnuts, and other varieties provide different combinations of unsaturated fats, fiber, protein, and micronutrients. Choosing unsalted or lightly salted varieties is a simple way to enjoy their benefits without adding unnecessary sodium.

Of course, the lesson isn’t that we should eat nothing but nuts and olive oil—or feel guilty about enjoying our favorite tasty butter, cheese, or chocolate. It’s simply that the sources of fat we choose most often matter more than any individual meal—and that we’d be wise to make choices that prioritize the best without restricting the occasional indulgence. After decades of treating fat as something to fear, that’s a considerably more satisfying (and fun) way to eat.

Have a beauty or wellness trend you’re curious about? We want to know! Send Vogue’s senior beauty & wellness editor an email at beauty@vogue.com.

• Have a beauty or wellness trend you’re curious about? We want to know! Email Margaux at beauty@vogue.com.

• The Vogue Runway app has expanded! Update to the latest version to see all Vogue content, as well as new features like our Runway Genius quiz, Group Chats, and posts from Vogue contributors.