Key takeaways
- The 2025–2030 Dietary Guidelines say saturated fat should not exceed 10% of daily calories, tell cooks to put oils such as olive oil first, and list butter and beef tallow as other options1.
- A 2020 Cochrane review of 15 trials, as summarized in American Family Physician, found that cutting saturated fat lowered combined heart and stroke events by 17%, though the new guidelines’ scientific report reads those trials more skeptically39.
- FDA ruled in 2015 that partially hydrogenated oils, once the major source of artificial trans fat, are not generally recognized as safe, and the final compliance date passed on January 1, 20215.
- U.S. adults get only about 90 milligrams a day of the omega-3s EPA and DHA from food, and the body turns less than 15% of plant omega-3 into them, so fish matters6.
- A tablespoon of beef tallow carries about 6.4 grams of saturated fat, versus about 1.9 grams in olive oil and 1.0 gram in canola oil, according to USDA data13.
The food pyramid the federal government unveiled in January 2026 has a stick of butter in the middle. Salmon, vegetable oil and walnuts share that tier, and a ribeye steak sits at the top, STAT reported2.
The same Dietary Guidelines keep a decades-old rule: saturated fat, the kind concentrated in butter and beef fat, should not exceed 10% of daily calories1. They also say, “Other options can include butter or beef tallow” for cooking1.
Critics from very different camps, from the Center for Science in the Public Interest to Nina Teicholz of the Nutrition Coalition, said those two messages are hard to reconcile2. The American Heart Association warned that the advice on red meat and salt could push people past saturated fat and sodium limits2.
If you’re confused, you’re paying attention. Beneath the noise, some fat findings are solid, a few are argued in good faith, and the kitchen choices are simpler than the politics.
Every fat is a blend, measured by the tablespoon
No fat is purely one type. Butter, olive oil and canola oil each blend saturated, monounsaturated and polyunsaturated fats, and USDA’s food data show the proportions differ widely131415.
- Saturated fat is concentrated in animal fats. By USDA’s numbers, about half the fat in beef tallow is saturated, and close to two-thirds of the fat in butter1315. Olive oil is about 14% saturated and canola oil about 7%1315.
- Monounsaturated fat is the main fat in olive oil, mostly in the form of oleic acid12. High-oleic sunflower oil, as its name says, is rich in it too13.
- Polyunsaturated fat includes omega-6 and omega-3 fats. A tablespoon of high-linoleic safflower oil has about 10 grams, canola about 4 grams and olive oil about 1.4 grams14.
- Trans fat came mostly from partially hydrogenated oils, which FDA has phased out5.
Some polyunsaturated fats are essential, meaning food must supply them. Alpha-linolenic acid (ALA), found in canola oil, walnuts and flaxseed, is the only essential omega-3, according to NIH’s Office of Dietary Supplements (ODS)6.
Trials favor cutting saturated fat, and experts split over what replaces it
A 2020 Cochrane review, a careful summary that pools randomized trials, examined 15 trials with 56,675 adults, according to a 2021 summary in American Family Physician3. People cut saturated fat for at least two years, and follow-up averaged 4.7 years3.
Combined cardiovascular events, such as heart attacks and strokes, fell by 17%3. In practical terms, about 1 in 56 people without heart disease who cut back avoided an event during the trials3. Death rates, from heart disease or anything else, didn’t change clearly3.
What you eat instead may matter a great deal. In a 2017 presidential advisory, the American Heart Association (AHA) found that in the trials it judged most reliable, replacing saturated fat with polyunsaturated vegetable oil lowered heart disease by about 30%, a benefit similar to statin drugs4.
Swapping in refined carbohydrates such as white bread didn’t help; it tracked with 1% more coronary disease4. Whole grains tracked with 9% less4. The Cochrane review was more cautious: no single replacement reached statistical significance on its own, though polyunsaturated fat and carbohydrate both trended toward benefit3.
The scientific report released with the new guidelines goes further. It argues that some older trials were muddied by other changes. In the Oslo Diet Heart Study, for example, the diet group also ate sardines and cod liver oil9.
Set those trials aside, the report concludes, and swapping saturated fat for oils rich in linoleic acid, the main omega-6 fat, doesn’t reduce heart disease or deaths9. It rated its own certainty moderate for deaths and very low for heart events9.
Much of the expert split comes down to which old trials deserve to count. And the AHA’s advice isn’t “fat is bad”: it doesn’t recommend cutting total fat for its own sake4.
The new guidelines on butter, tallow and full-fat dairy
What the 2025–2030 guidelines say, in plain terms1:
- Whole foods rich in healthy fats include meats, poultry, eggs, omega-3-rich seafood, nuts, seeds, full-fat dairy, olives and avocados.
- When cooking or adding fat, put oils that supply essential fatty acids first, such as olive oil. Butter or beef tallow are other options.
- Saturated fat should not exceed 10% of calories. Sharply limiting highly processed foods helps meet that goal.
- Include full-fat dairy with no added sugars. The dairy goal is three servings a day on a 2,000-calorie pattern.
The document also admits a gap: “More high-quality research is needed,” it says, to know which fats best support long-term health1.
The 2025 advisory committee, the outside scientists who reviewed the research first, put the emphasis elsewhere. According to Stanford’s Christopher Gardner, a committee member, their strongest saturated fat finding was that replacing butter, beef tallow and lard with vegetable oils improves LDL, the so-called bad cholesterol2.
Dairy fat is where reasonable experts split most. The AHA’s 2017 advisory found that dairy fat raises LDL, and that replacing it with polyunsaturated fat was linked to about 24% lower cardiovascular risk4. Yet Tufts University’s Dariush Mozaffarian told STAT that a 10% cap isn’t necessary and that Americans fall shortest on seafood and plants2. His Tufts colleague Alice Lichtenstein noted that butter, tallow and dairy fat aren’t sources of essential polyunsaturated fats2.
For many families, butter, lard, ghee and tallow are heritage foods with one ingredient, and that deserves respect. The trials above tested people’s everyday fat over years, not an occasional pat of butter on vegetables3. For the fat you reach for at most meals, the balance of evidence favors plant oils.
Trans fat is the one fat fight that’s over
Most of the trans fat in American food once came from partially hydrogenated oils, made by a process that turns liquid vegetable oil into a fat that’s solid at room temperature5. In 2015, FDA determined that partially hydrogenated oils were no longer “generally recognized as safe”5.
Manufacturers couldn’t add them to most foods after June 18, 2018, and FDA extended the final compliance date to January 1, 20215. FDA says the change is preventing thousands of heart attacks and deaths each year5.
The ban didn’t touch the small amounts of trans fat that occur naturally in milk, butter, cheese and meat5. The new guidelines don’t mention trans fat at all1. It’s a rare case where a food-industry shift, pushed by regulators, settled a public-health fight.
Olive oil and fish have the strongest whole-food evidence
The best-known olive oil trial had to be retracted and redone. PREDIMED assigned 7,447 adults at high heart risk to a Mediterranean diet with extra-virgin olive oil, the same diet with mixed nuts, or a control diet built on advice to cut fat8.
In June 2018, the New England Journal of Medicine retracted the original 2013 paper. Some household members had been enrolled together without random assignment, and at one of 11 sites, whole clinics rather than individuals were assigned to diets8.
The researchers reanalyzed the data to account for those problems, then ran it again without 1,588 participants whose assignments were known or suspected to be off8. Cardiovascular disease was still about 30% lower in the two Mediterranean groups than in the control group8. Even famous findings deserve rechecking.
FDA says strong evidence links eating fish, as part of a healthy diet, to heart health benefits7.
Fish also brings something plants can’t easily match. The body converts less than 15% of plant ALA into EPA and DHA, the long-chain omega-3s in seafood, and U.S. adults get only about 90 milligrams of EPA and DHA a day from food6. Three ounces of cooked salmon supplies well over 1 gram of the two combined, and canned sardines about 1.2 grams6.
The AHA suggests one to two servings of seafood a week6. For pregnancy and breastfeeding, FDA and EPA advise two to three 4-ounce servings a week of lower-mercury “Best Choices” such as salmon, sardines, shrimp and canned light tuna. They advise avoiding king mackerel, marlin, orange roughy, shark, swordfish, Gulf of Mexico tilefish and bigeye tuna7.
The seed oil argument, briefly and fairly
“Seed oils” usually means canola, soybean, sunflower, safflower, corn and similar oils. Critics raise three concerns: they’re high in omega-6 fat, they’re refined in factories, and their polyunsaturated fats break down under heat. The new guidelines don’t name seed oils at all1.
Some of that has support. Oils richer in polyunsaturated fat are more sensitive to heat damage12. The guidelines’ scientific report estimates that linoleic acid now supplies about 7.6% of the calories in U.S. diets, several times more than in traditional diets, and says its effects on people haven’t been studied enough9.
One old trial gives critics real ammunition. In 2016, researchers from the University of North Carolina and the National Institutes of Health recovered unpublished data from the Minnesota Coronary Experiment, run from 1968 to 1973 with 9,423 patients in state mental hospitals and a nursing home11. Replacing butter and other saturated fats with corn oil lowered cholesterol, but patients whose cholesterol fell most had a higher risk of death, not lower11. The researchers cautioned that their data were incomplete and that calling corn oil harmful would be premature11.
Other evidence points the other way. A 2019 pooled analysis of 30 cohort studies in 13 countries, with 68,659 people, measured linoleic acid in blood or fat tissue rather than relying on food diaries10. People near the top of the range had a 22% lower risk of cardiovascular death than people near the bottom10. Studies like this follow people rather than assign diets, so they can’t prove cause.
A later article in this series weighs the seed oil case in full. For now, the evidence doesn’t show that ordinary amounts of these oils harm the heart, and repeated high-heat frying is a separate issue.
Smoke point matters less than you’ve been told
Many cooks pick oils by smoke point, the temperature at which an oil starts to smoke. One lab’s tests suggest that’s a weak guide.
Researchers at Modern Olives, an Australian olive oil company and laboratory, heated 10 common oils in pans for 20 minutes and in deep fryers for six hours12. Smoke point did a poor job of predicting how much an oil broke down. An oil’s polyunsaturated fat content and its resistance to oxidation predicted it better12.
In their tests, extra-virgin olive oil held up best, with coconut oil a close second and other virgin and high-oleic oils next12. Read that with the funding in mind: an olive oil lab found olive oil performed well. Its basic chemistry point, that fats with more double bonds are more fragile under heat, is the same one seed oil critics make12.
Three habits matter more than the number on the bottle:
- Use moderate heat. The new guidelines favor baking, broiling, roasting, stir-frying and grilling over deep-frying1.
- Don’t reuse frying oil over and over. Trans fat and other breakdown products rise with high temperature and repeated use12.
- Match the oil to the job. Save the most polyunsaturated oils for dressings and low heat.
A fat swap table and an oil pantry guide
Fat swaps worth making
| Instead of | Try | Why | Evidence rating |
|---|---|---|---|
| Butter or tallow as the everyday cooking fat | Olive or canola oil, keeping butter for flavor | Unsaturated oils lower LDL, and cutting saturated fat cut combined heart events in trials23 | for LDL; the event benefit is disputed9 |
| Low-fat cookies, crackers and white bread in place of fat | Whole-grain foods and unsaturated fats | Low-fat, higher-carb diets didn’t cut heart disease; whole grains tracked with 9% less4 | that the low-fat swap doesn’t help |
| Coconut oil as a heart-health food | Olive or canola oil | Coconut oil raises LDL with no known offsetting benefit4 | (to coconut oil as heart-healthy) |
| Fish oil pills as your only omega-3 | Two servings of low-mercury fish a week | FDA ties eating fish to heart benefits7 | for eating fish; pills are covered in our anti-inflammatory article |
| Deep-fried foods cooked in reused oil | Roasting, baking or stir-frying | Reused frying oil builds up breakdown products, including trans fat12 | (mostly lab tests) |
Pantry guide to oils (per tablespoon, USDA data)131415
| Fat | Saturated | Polyunsaturated | Best uses |
|---|---|---|---|
| Extra-virgin or regular olive oil | 1.9 g | 1.4 g | Everyday sautéing, roasting, dressings |
| Canola oil | 1.0 g | 3.9 g (1.3 g is omega-3 ALA6) | Baking, sautéing, neutral-flavored cooking |
| High-oleic sunflower oil | 1.4 g | 0.5 g | Higher-heat cooking |
| Sesame oil | 1.9 g | 5.7 g | Flavor and finishing, moderate heat |
| High-linoleic safflower oil | 0.8 g | 10.1 g | Dressings and low heat |
| Beef tallow | 6.4 g | 0.5 g | Occasional flavor, counted toward the 10% limit |
| Butter (1 pat, not 1 tablespoon) | 2.6 g | 0.2 g | Flavor at the table, in small amounts |
What the evidence shows
| Claim | Evidence rating | What it rests on |
|---|---|---|
| Swapping saturated fat for unsaturated plant oils lowers LDL cholesterol | The advisory committee’s strongest finding; even the skeptical scientific report agrees cholesterol falls29 | |
| Cutting saturated fat lowers combined heart attacks and strokes | Cochrane review of 15 trials, 17% fewer events3; the guidelines’ scientific report disputes which trials count9 | |
| Polyunsaturated plant oils are the best replacement for preventing heart events | Mixed results: AHA’s core trials, about 30% less heart disease4; Cochrane, a trend short of significance3; scientific report, no benefit9 | |
| Cutting saturated fat lowers death rates over 2 to 8 years | No clear change in deaths in the Cochrane review3 or the scientific report9 | |
| Industrial trans fat raises heart disease | FDA determination and AHA advisory45 | |
| A Mediterranean diet with extra-virgin olive oil lowers heart events in high-risk adults | One large trial, reanalyzed after a retraction, still about 30% lower8 | |
| Eating fish as part of a healthy diet benefits the heart | FDA and EPA’s review of the evidence7 | |
| Ordinary amounts of seed oils harm the heart | Cohort data point to benefit; one incomplete old trial raised questions; high intakes are understudied91011 | |
| Full-fat dairy is neutral or good for the heart | Dairy fat raises LDL, but experts disagree on its overall effect24 | |
| An oil’s fat makeup predicts heat damage better than its smoke point | One industry lab’s tests of 10 oils12 |
Questions readers ask
Is butter bad for me?
A little butter isn’t the problem. The evidence is about your everyday cooking fat: trials found fewer heart events when people cut saturated fat, and the AHA found the clearest benefit when plant oils replaced it34. Use butter for flavor and olive or canola oil for most cooking.
Should I take fish oil instead of eating fish?
Both raise EPA and DHA, which ODS says you need to get directly, from food or supplements6. FDA ties eating fish to heart benefits, and the new guidelines call for omega-3-rich seafood17. Our article on anti-inflammatory claims explains the mixed results of fish oil trials.
Can I cook with extra-virgin olive oil?
Yes, for most home cooking. In lab tests by an olive oil company, it held up better than oils with higher smoke points12. Keep the heat moderate and don’t reuse it for repeated frying.
The bottom line
The fat question isn’t settled in every corner, but its center holds. Unsaturated plant oils as your everyday fat, fish about twice a week and no industrial trans fat have the broadest support. The arguments that remain, over which old trials to trust, dairy fat, butter in moderation and seed oils, are real, and they’re narrower than the headlines suggest.
Keep the traditional fats you love for flavor, cook mostly with olive or canola oil, and let whole foods such as fish, nuts, olives and avocados carry the rest.
Related reading
About this article
This article was researched using the federal Dietary Guidelines and their scientific report, FDA, NIH and USDA sources, a Cochrane review summary, a heart association advisory, peer-reviewed studies and news reporting on the guidelines, listed below, and was reviewed in October 2026. It is general education, not medical, legal or financial advice..
Sources
- U.S. Department of Agriculture and U.S. Department of Health and Human Services. “Dietary Guidelines for Americans, 2025–2030.” January 2026. cdn.realfood.gov
- Todd S, Cooney E, Cueto I. “How saturated fats lost, and won, on new food pyramid.” STAT, January 8, 2026. statnews.com
- Rivera V, Baird D. “Reducing Saturated Fat Intake to Decrease the Risk of Cardiovascular Disease” (Cochrane for Clinicians, on Hooper L, Martin N, Jimoh OF, et al., Cochrane Database of Systematic Reviews, 2020, CD011737). American Family Physician, September 2021. aafp.org
- American College of Cardiology. “AHA Presidential Advisory on Dietary Fats and CVD: Ten Points to Remember” (on Sacks FM, Lichtenstein AH, Wu JHY, et al., Circulation, 2017). ACC, June 26, 2017. acc.org
- U.S. Food and Drug Administration. “Trans Fat.” FDA, content current as of April 30, 2024. fda.gov
- NIH Office of Dietary Supplements. “Omega-3 Fatty Acids: Fact Sheet for Health Professionals.” ODS, updated September 2026. ods.od.nih.gov
- U.S. Food and Drug Administration. “Advice about Eating Fish.” FDA and EPA, content current as of March 5, 2024. fda.gov
- Harvard T.H. Chan School of Public Health, The Nutrition Source. “PREDIMED Study Retraction and Republication.” June 22, 2018. nutritionsource.hsph.harvard.edu
- U.S. Department of Health and Human Services and U.S. Department of Agriculture. “The Scientific Foundation for the Dietary Guidelines for Americans, 2025–2030.” 2026. cdn.realfood.gov
- Marklund M, Wu JHY, Imamura F, et al. “Biomarkers of Dietary Omega-6 Fatty Acids and Incident Cardiovascular Disease and Mortality: An Individual-Level Pooled Analysis of 30 Cohort Studies.” Circulation, 2019;139(21):2422–2436. research.wur.nl
- University of North Carolina Health Care. News release on Ramsden CE, et al., BMJ, 2016, re-evaluation of the Minnesota Coronary Experiment. ScienceDaily, April 12, 2016. sciencedaily.com
- de Alzaa AF, Guillaume C, Ravetti L. “Cooking with Extra Virgin Olive Oil.” In: Olive Oil: New Perspectives and Applications. IntechOpen, 2021. intechopen.com
- USDA National Agricultural Library. “Saturated Fat” nutrient list, USDA National Nutrient Database for Standard Reference Legacy (2018), a FoodData Central data type. nal.usda.gov
- USDA National Agricultural Library. “Polyunsaturated Fat” nutrient list, Standard Reference Legacy (2018). nal.usda.gov
- USDA National Agricultural Library. “Total Fat” nutrient list, Standard Reference Legacy (2018). nal.usda.gov