Fish oil concentrates marine fat at 902 kcal per 100 g. A 2024 meta-analysis of 18 RCTs in 134,144 people (Dinu et al., Eur J Prev Cardiol 2024) found fish oil supplements cut heart attacks by 11% (RR 0.89) and cardiovascular death by 8% (RR 0.92). Effects were larger with concentrated prescription products.
How should I track Fish oil, herring?
With calorie-dense foods like Fish oil, herring, a kitchen scale is your best friend. Research shows that portion estimation errors reach 50–200% for fats and oils (Almiron-Roig et al., Appetite 2013) — even a tablespoon off can mean 40–120 extra calories. Weigh on a scale rather than eyeballing — this applies to both liquid oils and solid fats like butter. If you use cooking sprays, note that "0 calorie" labels are per fraction-of-a-second spray — a realistic burst is closer to 5–10 calories, and multiple sprays add up.