In 1955, physiologist Ancel Keys warned at the International Congress on Cardiology about the role of certain dietary fats in heart disease—a debate that would shape nutritional guidelines. Less well known: Nutritionist Marion Nestle later played a significant role in exposing industry influences on fat recommendations and strengthening consumer education. Today we know: Not all fats are created equal. If you want high performance, you must differentiate—between fats that drive inflammation and those that protect energy, the brain, and longevity.

Fat is not just a calorie, but a building block. It provides energy, shapes cell membranes, and regulates signaling pathways. Three groups dominate: saturated fatty acidsmostly solid, e.g., in butter and coconut oil, monounsaturated fatty acidse.g., oleic acid in olive oil, polyunsaturated fatty acidsomega-3 and omega-6, essential as the body cannot produce them. Problematic are trans fatsfatty acids arising from industrial partial hydrogenation that promote inflammation and atherosclerosis. For omega fats, the ratio matters: A high omega-6:omega-3 ratiocommonly found in Western diets 10:1 to 25:1 favors inflammatory processes, while a more balanced ratio has a regulatory effect. Notable exceptions: DHA/EPAmarine omega-3 fatty acids, important for brain, heart, and inflammation regulation and CLA – conjugated linoleic acidspecial omega-6 isomers from ruminant fats; show some beneficial effects on fat metabolism, with individual variability. Critical for performance is the "matrix": Fats affect outcomes depending on their source (fish vs. frying oil), processing (fresh vs. oxidized), and context (vegetables, fiber, overall pattern).

Industrial trans fats increase LDL, lower HDL, and promote atherogenic inflammation—effects that lead to significant vascular lesions and oxidative stress in animal models, explaining the connection to coronary artery disease ^{[1] [2]}. A high consumption of ultra-processed, fat- and sugar-rich products shifts the entire metabolic milieu: Increased weight gain, insulin resistance, and systemic inflammation are the results—a clear driver for cardiometabolic diseases and reduced quality of life ^{[3] [4]}. The ratio of omega-6 to omega-3 acts like an inflammation thermostat: A high ratio correlates with pro-inflammatory markers and obesity, while a more balanced ratio is associated with less inflammation and can shift gut microbiota in a favorable direction ^{[5] [6]}. At the same time, genetic analyses urge nuance: There is no simple "n-6 bad, n-3 good" dichotomy for all inflammatory markers—the context matters ^[7]. Meta-analyses suggest that omega-3 can moderately improve attention, processing speed, and global cognition—relevant for sustainable performance—though the effects are small to moderate ^{[8] [9]}.

The evidence on omega-3 and brain performance is now broad but nuanced. A large meta-analysis of randomized studies found dose-dependent, yet overall moderate gains in attention, processing speed, and global cognitive abilities. The authors emphasize that long-term RCTs are needed and that effects can be curvilinear depending on dose and domain—important for realistic expectations regarding supplements ^[8]. A second review aggregated randomized studies and showed a small but significant advantage in global cognition (MMSE), without clear dose or duration dependence—this suggests a threshold rather than a linear effect, and supports the combination with lifestyle measures such as exercise, sleep, and nutrition ^[9]. On the other hand, experimental models illustrate how trans fats directly fuel inflammation and atherogenesis: In mouse models, TFA diets enlarged diet-induced plaques, increased oxidized LDL as well as vascular ROS, and triggered NADPH oxidase in vascular smooth muscle cells—a plausible mechanism for increased coronary risk ^[2]. Together, a consistent picture emerges: Quality and degree of processing of fats modulate inflammatory pathways, vascular integrity, and cognitive resources—key factors for longevity and high performance.

- Eliminate trans fats from your daily routine: Avoid industrially hydrogenated fats in baked goods and fried products. Many countries regulate TFA, but residues can be found in imported or older formulations. Shortcut: Check the ingredient list for "hydrogenated/partially hydrogenated fats" and choose alternatives ^[10].
- Increase omega-3 intake intelligently: Two fish meals per week with salmon, mackerel, or herring often meet needs. Not in the mood for fish? Opt for certified omega-3 supplements (EPA/DHA). Expect realistic, moderate benefits for attention, processing speed, and global cognition—especially in conjunction with sleep, exercise, and stress management ^{[8] [9]}.
- Balance the omega-6:omega-3 ratio: Cook more frequently with olive oil, reduce highly processed snack oils rich in linoleic acid, and incorporate flaxseed, walnut, or algae sources. The goal is balance, not a zero strategy—this supports inflammation regulation and a favorable microbiota ^{[5] [6]}.
- Use CLA judiciously: Beef and lamb provide CLA that can influence fat metabolism. Since results are inconsistent and dose as well as individual factors count, consume moderately, prefer grass-fed sources, and limit red meat overall ^[11].
- Read labels like a pro: Check nutritional information and ingredient lists for types of fats. Studies show that those who use labels are more likely to make better choices—yet many underestimate the fat content of certain products. Train your eye for portion sizes and hidden fats to avoid missteps ^{[12] [13]}.

Fats are tools—some sharpen your performance, while others dull it. Start this week with two omega-3-rich meals, replace fried snacks with fresh options, and make label reading a mandatory task. This way, you can turn down the inflammation dial and lay the foundation for energy, focus, and a long, healthy life.