Natto is fermented whole soybeans with a sticky texture and distinctive aroma. Per 100 g: 19.4 g protein, 5.4 g fiber. Soy protein matches dairy for muscle outcomes (Reid-McCann et al., Nutr Rev 2025), and the fermentation carries live cultures plus K2-producing bacteria. Traditional Japanese breakfast food — acquired taste for newcomers. Log by weight.
How should I track Natto?
Natto is high in iron. When tracking Natto, the dry-vs-cooked distinction is critical. Legumes absorb roughly 2–3 times their weight in water during soaking and cooking, so 100 g dry becomes 250–300 g cooked. Always check which form the nutrition values refer to. A meta-analysis of 43 RCTs (Reid-McCann et al., Nutr Rev 2025) found plant protein matches dairy for muscle outcomes — so tracking precision matters just as much here. If you use canned legumes, drain and rinse to reduce sodium by about 40%. Weigh on a kitchen scale for the most reliable count.