Best Fats for Weight Loss: 2026 Guide

Why unsaturated fats help (and what to limit)

• Unsaturated fats (MUFA & PUFA) support cardiometabolic health and, when swapped for saturated/trans fats or refined carbs, can improve your lipid profile and make meals more satisfying—useful for sticking to a calorie target.^{2, 3}
• Saturated fats (butter, lard, coconut/palm) should be limited; replace with liquid non-tropical vegetable oils where possible.⁴
• Artificial trans fat from partially hydrogenated oils has been removed from the U.S. food supply—still, check labels and avoid products listing “partially hydrogenated.”^{5, 6}

Best examples (with portions)

Liquid plant oils

Extra-virgin or regular olive oil, canola, soybean, sunflower (non-tropical) — great for cooking and dressings. Use to replace butter/shortening.

• 1 Tbsp olive oil ≈ 119 kcal (14 g fat).⁷

Nuts & nut butters

Almonds, walnuts, pistachios, peanuts, pecans (and their unsweetened butters) add crunch, minerals, and fiber. Meta-analyses show nut intake does not cause weight gain and may aid weight control when calories are managed.⁸

• 1 oz almonds ≈ 164 kcal (14 g fat, ~6 g protein).⁹

Seeds

Chia, flax, hemp, pumpkin — deliver fiber and ALA omega-3s; great in yogurt/oatmeal/smoothies.

Avocado & olives

Rich in MUFA and fiber; ideal on grain bowls, eggs, tacos, and salads.

• ½ medium avocado ≈ 160–170 kcal (mostly MUFA).^{10, 11}

Fatty fish (EPA/DHA omega-3s)

Salmon, sardines, mackerel, trout, herring — aim for 2 servings/week for heart benefits (and protein-rich meals that keep you full).¹²

Quick portion cheat-sheet

How to use fats for weight loss (without stalling)

1. Substitute, don’t just add. Swap butter or creamy sauces for olive-oil vinaigrette; nuts instead of chips; salmon instead of high-fat processed meats.^{3, 12}
2. Pair with protein + fiber. A fat + protein + fiber combo improves fullness (e.g., salmon + veggies + olive-oil dressing; Greek yogurt + chia + berries). See our high-protein guide.
3. Mind portions. Oils and nut butters are calorie-dense—measure them. If you track, keep fat near 20–35% of calories (e.g., ~40–70 g/day on ~1,800 kcal).¹
4. Use nuts strategically. RCT/meta-analyses show no excess weight gain from nuts when calories are managed; they can support long-term weight control.⁸
5. Mediterranean pattern works. High-unsaturated-fat dietary patterns (olive oil, nuts, fish) are compatible with weight management and long-term maintenance.^{13, 14}

Label & cooking tips

• Choose non-tropical oils with <4 g saturated fat per Tbsp and no “partially hydrogenated” in ingredients.^{3, 5}
• Dressings/spreads: Pick olive-oil-based dressings; choose nut butters with only “nuts + salt.”
• Fish: Aim for 2 servings/week of fatty fish; avoid deep-fried prep.¹²

Want a simple plan? Start here: best weight-loss program · set calorie goals · curious about avocados & weight or cardiologists on high-fat diets?

FAQs

Can eating more healthy fat make me gain weight?

Any fat can cause weight gain if total calories exceed your needs. The key is replacing less-healthy fats/refined carbs with unsaturated fats while staying in a deficit.

Are nuts “too high-calorie” for weight loss?

They’re calorie-dense, but trials/meta-analyses show nuts don’t promote weight gain when calories are managed and may improve satiety and diet quality.⁸

Is olive oil better than butter for weight loss?

Olive oil has heart-healthy MUFA. Replacing butter with olive oil supports cardiometabolic health, and cohort data suggest less weight gain over time when olive oil intake rises.^{3, 15}

References

1. U.S. Dietary Guidelines for Americans 2020–2025 — Adults typically aim for 20–35% of calories from fat. dietaryguidelines.gov.
2. AHA Scientific Statement: 2021 Dietary Guidance to Improve Cardiovascular Health. Circulation.
3. American Heart Association — Healthy cooking oils & swap guidance (choose non-tropical liquid vegetable oils). heart.org.
4. American Heart Association — Saturated fats: why to limit and what to use instead. heart.org.
5. FDA — Final determination on partially hydrogenated oils (PHOs) not GRAS. fda.gov.
6. FDA — Trans fat & labeling overview. fda.gov.
7. USDA FoodData Central — Olive oil, 1 Tbsp ≈ 119 kcal. myfooddata.com.
8. Nishi SK, et al. Nuts & body weight (systematic review & meta-analysis): nuts do not cause weight gain; may reduce adiposity. Open access.
9. MyFoodData — Almonds, 1 oz nutrition. myfooddata.com.
10. MyFoodData — Avocado, nutrition and calories. myfooddata.com.
11. Ford NA, et al. Nutritional composition of Hass avocado pulp (2023). PMC.
12. American Heart Association — Fish & omega-3s: eat fish at least twice per week. heart.org.
13. Estruch R, et al. High-fat Mediterranean diet: body weight/waist outcomes from PREDIMED (secondary analysis). Lancet Diabetes Endocrinol.
14. Poulimeneas D, et al. Mediterranean diet adherence linked with better weight-loss maintenance. Nutrients (open access).
15. Guasch-Ferré M, et al. Changes in olive-oil intake & long-term body weight (NHS/HPFS, 2025). AJCN (PubMed).

Links verified September 2025. Educational content only; not medical advice.