What is natto and what does it taste like?

Learn what natto is, why it smells and feels the way it does, how it is eaten at breakfast, and tips for trying it as a visitor.

Published October 20, 2026 at 7:57 PM JST | By Tokyo Paul

Quick answer: Natto is a traditional Japanese food made from whole soybeans fermented with a bacterium, usually eaten cold over rice at breakfast. It is sticky and stringy, with a strong, cheese-like smell and an earthy, savory flavor. Many people find it an acquired taste, and it is more popular in eastern Japan than in Kansai.

What natto is

Natto is made from whole soybeans fermented with Bacillus subtilis var. natto, a type of bacterium. The soybeans are soaked, steamed, mixed with the bacteria and fermented in warm conditions for about a day, then chilled so that the texture develops. The result is a sticky mass of soft beans coated in long, stretchy strings. Britannica describes it as a sticky mass of beans that keeps its shape, with a strong smell.

It is one of the best-known fermented foods of Japan and is usually sold in small containers, often in packs of two to four, available in nearly every supermarket and convenience store. Each pack typically comes with a small packet of sauce and another of mustard, ready to mix. It is eaten cold or at room temperature rather than cooked.

What natto tastes and smells like

Natto has a strong smell, often compared to a pungent aged cheese, with a hint of ammonia in some cases. The flavor is savory and earthy, and the fermentation produces glutamic acid, which gives an umami taste. Most of the shock for newcomers comes from the texture, which is slimy and stringy, and stirring makes the strings multiply.

Many people consider natto an acquired taste. A 2009 survey reported in one reference work found that about 70 percent of respondents thought the taste pleasant, but opinions vary and many first-time tasters need a few tries. Flavor can be softened by adding seasonings such as soy sauce, mustard, scallions or a little grated daikon, and some versions are designed to be milder or less sticky.

How natto is eaten

The usual way is over a bowl of hot rice. Open the tray, remove the film, add the sauce and mustard from the packets, and stir the beans with chopsticks for a good while, often dozens of turns, until they become frothy and the strings thicken. Then pour the mixture over rice and eat. Some people add chopped scallions, a raw egg yolk or a little kimchi.

Natto also appears in other dishes. You can find it in miso soup, on toast, in sushi rolls called natto maki, in omelets, and as a topping on noodles. Dried or fried versions exist for people who prefer a crunchier, less sticky form, and a less sticky variety called mamenoka was created for those who dislike the usual texture.

Origins, breakfast and regional habits

The origin of natto is not settled. Britannica says it is thought to date back about 1,300 years, and some scholars link it to the introduction of fermented soybean foods from China. Legends credit famous historical figures, but there is no single confirmed story. The name may be linked to a Buddhist temple kitchen, which hints at an early role in temple cooking.

Natto is a classic part of a Japanese breakfast set, served with rice, miso soup, a small fish and pickles. Hotels and inns in Japan that serve Japanese breakfasts often include it as a small side dish, so travelers are likely to see it on morning menus. Britannica notes that it is a popular breakfast food in eastern Japan, usually mixed with soy sauce and mustard.

Consumption is higher in the eastern regions of Japan, including Kanto, Tohoku and Hokkaido, and lower in Kansai, the region around Osaka and Kyoto. That regional difference is often discussed, but it is a general trend, and many people in every region enjoy natto. If you travel across regions, you may notice differences in how widely it is offered.

Cost, buying natto and what to look for

Natto is typically inexpensive and sold in packs at supermarkets and convenience stores, as well as at some restaurants that serve it as a side dish. Prices vary by brand and size, so check the shelf label for current amounts. Packs often contain small beans or large beans, and the sauce packets vary in flavor, so reading the label helps you choose.

If you want to try it, a convenience store pack is an easy first step. Eat it cold, with rice, and keep the container tidy since the strings can be messy. Natto is perishable, so store it in a refrigerator and check the date on the pack. Travelers staying in apartments or with kitchens can buy a pack to try for breakfast.

Special cases, health and allergies

Natto is made from soybeans, so anyone with a soy allergy should avoid it. The sauce packets often contain soy sauce and may also contain wheat, and some contain fish extracts, so people with allergies or dietary restrictions should read ingredient lists carefully. Vegetarian and vegan travelers can often eat plain natto but should check the sauce. Natto contains vitamin K, so people taking blood-thinning medicine should ask a doctor. This guide shares general cultural information, not professional advice; for health questions, talk with a doctor.

Reference works list natto as a source of protein, iron, and some vitamins. Britannica also notes that claims made on Japanese television that natto is a weight-loss cure have not been substantiated. Treat health claims about any single food with caution. Children often enjoy it with rice if the sauce is mild, but the strong smell may be difficult for some, so offering a small portion is a gentle way to begin.

Common mistakes and planning tips

A common mistake is eating natto without stirring it, which leaves the flavor flat and the beans hard to pick up. Another is expecting an easy first taste; a calm approach and a small portion are better. Some travelers also avoid it because of the smell, but a strong smell is part of the food and fades once it is mixed with rice and seasonings.

For planning, try natto at a Japanese breakfast, and ask whether a milder version is available if you are unsure. Keep a few tips in mind: mix well, add rice, and use sauce sparingly at first. If you do not enjoy it, no one will mind, and Japanese people themselves differ in how much they like it. Check restaurant menus, which usually show natto dishes.

Frequently Asked Questions

Is natto safe for visitors to eat?

Natto is a common food eaten by many people in Japan every day. It is made from soybeans fermented under controlled conditions. People with soy allergies or specific health concerns should avoid it or ask a doctor first. Always check the use-by date on packaged natto.

Why is natto sticky?

The stickiness comes from the fermentation, in which the bacteria break down the soybeans and produce a stretchy, slimy coating. Stirring the beans pulls out the strings and develops the flavor, which is why most instructions say to stir well before eating.

Is natto a breakfast food only?

It is most often eaten at breakfast, but it is also eaten at lunch or dinner as a side dish or a topping, and it appears in dishes such as natto sushi, toast, noodles and soup. There is no rule against eating it at any time of day.

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