Eating During Pregnancy in Japan: What's Safe, What to Limit & Japanese-Specific Foods

May 30, 2026 Maternity Prep Navigator Editorial ~9 min read

If you are pregnant in Japan, you may find yourself navigating familiar pregnancy diet questions — sushi, caffeine, alcohol — alongside a cuisine that uses ingredients you may not have thought about before: raw egg, fermented soy, seaweed, and more. This guide organizes the most commonly asked questions by category so you can bring informed questions to your next prenatal checkup. Think of it as a starting point for a conversation with your doctor or dietitian, not as a rule list.

1. A Useful Framework: Three Categories

Rather than a long list of "do not eat" foods, it can help to think in three groups:

Every person's situation is different, and your doctor or midwife at your prenatal checkups is the right person to give you personalized guidance. The sections below explain the reasoning behind each category so you can have a more informed conversation.

2. Generally Best to Avoid: Alcohol

Among all pregnancy diet topics, alcohol is the area where medical and scientific consensus is most consistent: there is no established amount of alcohol that has been determined to be safe during pregnancy. Major obstetric and health organizations in Japan and internationally generally recommend not drinking alcohol at all during pregnancy.

Alcohol can cross the placenta and reach the developing baby. The potential effects are well-documented in medical literature. If you are finding it difficult to stop drinking, please speak with your obstetrician or midwife — non-judgmental support is available.

Non-alcoholic beer and "zero alcohol" drinks are popular in Japan and widely available. Check the label, as some products labelled "non-alcoholic" (ノンアルコール) in Japan contain trace amounts of alcohol (typically less than 1%). If you have any concerns, consult your obstetrician.

3. Be Cautious About: Raw Fish & Sushi

This is one of the most common questions for pregnant people in Japan, where sushi and sashimi are a regular part of daily life.

The main concerns

Raw or undercooked fish and seafood carry a risk of foodborne illness from bacteria such as Listeria monocytogenes and parasites. Listeria infection during pregnancy can cause serious complications, including miscarriage, premature birth, and illness in the newborn. Parasitic risk varies by fish species and origin.

How Japanese women and doctors typically approach this

Many obstetric guidelines in Japan recommend that pregnant women be cautious about raw fish and choose to reduce or avoid sushi and sashimi, particularly during the first trimester when the pregnancy is most sensitive. That said, practices vary among individual doctors and households. Some doctors advise avoiding raw fish entirely during pregnancy; others say an occasional small amount from a reputable source is acceptable. Ask your own obstetrician for guidance specific to your situation.

4. Be Cautious About: Mercury in Large Fish

Japan's Ministry of Health, Labour and Welfare (厚生労働省, MHLW) has published guidance specifically for pregnant women on mercury in seafood. This is one of the clearest, most specific pieces of official guidance on pregnancy diet in Japan, and it is worth understanding before your next meal involving large fish.

Why large fish contain more mercury

Methylmercury accumulates up the food chain. Larger predatory fish that eat smaller fish — including certain tuna species, swordfish, and shark — tend to accumulate more methylmercury in their tissues over their lifetimes. Excessive methylmercury exposure during pregnancy is associated with potential effects on fetal neurological development, which is why public health guidance exists.

MHLW guidance overview

According to the MHLW guidance on fish and mercury for pregnant women (first issued 2005, revised June 2010), certain fish are classified by suggested intake frequency. The guidance uses a serving size of approximately 80 g as a reference. Below is a general summary of the categories — for the full and current list, always refer to the official MHLW document directly.

Canned tuna — widely used in Japan in rice balls (onigiri), sandwiches, and salads — is specifically noted in the MHLW guidance as not subject to the same intake limits. This is because canned tuna generally uses smaller, younger fish with lower mercury accumulation. That said, eating any single food in very large quantities is not nutritionally ideal — variety is generally recommended.

5. Be Cautious About: Raw Meat, Liver & Raw Egg

Raw and undercooked meat

Raw or undercooked meat carries a risk of Toxoplasma gondii infection (toxoplasmosis) as well as bacterial contamination. Toxoplasmosis during pregnancy can, in some cases, be transmitted to the fetus. In Japan, dishes such as yukhoe (raw beef, found at yakiniku restaurants), basashi (raw horse), and some forms of chicken sashimi (tori-sashimi) involve raw or minimally processed meat. Many Japanese obstetric guidelines suggest that pregnant women choose well-cooked meat options and be cautious about these dishes. If you have questions about specific dishes, your obstetrician can advise.

Liver

Liver is very high in vitamin A (retinol form). While vitamin A is an essential nutrient, excessive intake of preformed vitamin A (retinol, found in animal liver) during pregnancy has been associated with concerns about fetal development in the medical literature. This applies particularly to large amounts eaten regularly. Occasional moderate servings of liver are typically discussed differently from daily large consumption — talk with your doctor or dietitian about your overall intake if you eat liver regularly.

Raw egg

Raw egg carries a risk of Salmonella infection. In Japan, raw egg (tamagokake gohan — raw egg on rice — and other dishes served with a raw egg) is a deeply embedded culinary tradition. Japanese eggs are produced and handled under strict hygiene standards that reduce (though do not eliminate) the risk of Salmonella, and some Japanese obstetricians take a more relaxed view than international guidelines on this point. Practices vary. Many women choose to avoid raw egg during pregnancy as a precaution; others continue eating it following a discussion with their doctor. Ask your own obstetrician what they recommend.

6. Be Cautious About: Unpasteurized Cheese & Cured Meats

Cheese

Unpasteurized (raw milk) soft cheeses, as well as some mold-ripened soft cheeses, can carry Listeria. In Japan, imported cheeses such as brie, camembert, and some feta are sometimes unpasteurized — check the label. Hard cheeses (cheddar, gouda, parmesan) and processed cheeses (the sliced or spreadable types widely available in Japanese supermarkets) are generally considered lower risk because of their lower moisture content and processing. If you are unsure about a specific cheese, your obstetrician can advise.

Cured and processed meats

Items such as prosciutto, salami, and other ready-to-eat cured meats can carry Listeria. In Japan, namaham (raw ham / prosciutto) is widely available at supermarkets and Italian restaurants. Many pregnant women in Japan choose to avoid or reduce namaham during pregnancy; cooking it thoroughly (for example, briefly heating it) reduces the risk. Discuss with your doctor if you are unsure about specific products.

7. Be Cautious About: Caffeine (Coffee, Tea & Green Tea)

Japan is a tea-drinking country, and green tea in particular is a staple of daily life. Understanding caffeine content in common Japanese drinks is useful during pregnancy.

What the guidance says

Japan's Ministry of Health, Labour and Welfare does not publish a specific daily mg limit for caffeine intake during pregnancy, unlike some other countries (for reference, the UK Food Standards Agency's 2008 guidance suggests up to 200 mg/day for pregnant women, and Health Canada's 2010 guidance suggests up to 300 mg/day — both figures cited via Japan's MHLW reference page). However, general guidance from healthcare providers in Japan commonly suggests reducing caffeine intake during pregnancy — "cutting down rather than cutting out entirely unless advised otherwise" is a typical framing, though individual recommendations vary.

Approximate caffeine content in common Japanese drinks

The following approximate values are based on data published by Japan's Ministry of Health, Labour and Welfare (mhlw.go.jp, "Excessive caffeine intake from foods"). These are general references — actual caffeine content varies by product and preparation.

8. Generally Fine, With Some Awareness: Soy, Natto & Seaweed

Soy foods (tofu, miso, natto, edamame)

Soy foods are a major part of the Japanese diet and a valuable source of plant protein, calcium, and other nutrients. There is no established scientific consensus that ordinary consumption of soy foods during pregnancy poses a risk. Some older discussions around soy isoflavones and pregnancy have not produced consistent evidence of harm at typical dietary intake levels. Tofu, miso soup, edamame, and agedashi tofu are all commonly eaten by pregnant women in Japan without concern.

Natto (fermented soybeans) is nutritionally rich, particularly in vitamin K2 and protein, and is generally considered nutritious during pregnancy. One commonly mentioned caution in some older discussions was around vitamin K and blood thinners — if you are on any anticoagulant medication, let your doctor know you are eating natto regularly.

Seaweed (kombu, wakame, nori, hijiki)

Seaweed is nutritious and commonly eaten in Japan. Most types — nori (in sushi and onigiri), wakame (in miso soup and salads), and small amounts of kombu used in dashi stock — are generally consumed without concern during pregnancy.

Hijiki (a type of brown seaweed) has historically attracted attention because it can contain naturally occurring inorganic arsenic. Japan's Food Safety Commission has addressed this, noting that occasional consumption does not pose a concern, but regular daily consumption in large quantities is worth discussing with a healthcare provider if it forms a significant part of your diet. Iodine content in seaweed is also occasionally discussed — very large regular amounts of kelp (kombu) could affect thyroid function, but normal culinary use is generally not a concern. As with any food, variety and moderation are commonly recommended.

9. Herbs, Supplements & Herbal Teas: Ask First

The rule of thumb most often given by obstetric providers in Japan and internationally: check with your doctor before taking any supplement, herbal product, or traditional medicine during pregnancy. This includes:

• Herbal teas (herbal infusions) — Not all herbal teas are suitable during pregnancy. Some herbs have properties that may be worth discussing with your doctor. This does not mean herbal tea is dangerous, but it does mean the variety matters. Chamomile, rooibos, ginger tea (in moderate amounts) are commonly consumed without concern; high doses of concentrated herbal extracts are a different matter. If in doubt, ask your doctor.
• Chinese herbal medicine and kampo (漢方) — Kampo is widely used in Japan, including some formulations specifically aimed at pregnancy. Some kampo preparations are used by obstetricians under medical guidance; others are sold over the counter. If you are considering kampo during pregnancy, consult with your obstetrician or a licensed kampo practitioner rather than self-medicating.
• Supplements (vitamins, minerals, herbal) — More is not always better during pregnancy. Excessive intake of certain vitamins and minerals — particularly vitamin A (retinol form), vitamin D, and iron — can cause problems at very high doses. Folate (folic acid) supplementation is commonly recommended in early pregnancy; the appropriate dose and timing are something to confirm with your doctor. Do not take supplement recommendations from non-medical sources without checking with your healthcare provider first.

10. Key Nutrients During Pregnancy in Japan

A balanced Japanese diet is generally considered nutritionally suitable for pregnancy. Some nutrients are commonly discussed at prenatal checkups in Japan:

• Folate (folic acid / yosan) — Commonly recommended before conception and during early pregnancy. Found in leafy green vegetables, legumes, edamame, and fortified foods. Many obstetricians recommend supplementation, particularly in the first trimester; discuss the appropriate type and amount with your doctor.
• Iron (tetsu) — Iron-deficiency anemia is common during pregnancy. Foods rich in iron include hijiki (see the note on seaweed above), dried prunes, liver (see note above on vitamin A), tofu, natto, and leafy greens. Your doctor will monitor your blood iron levels through regular prenatal checkups.
• Calcium — Important for both mother and baby. Dairy products, tofu (particularly firm tofu set with calcium), small dried fish (niboshi), and leafy greens are common sources in the Japanese diet. Discuss with your doctor if you have concerns about calcium intake.
• DHA and omega-3 — Found in fish, particularly fatty fish such as salmon, aji, sardine, and saury. This is one reason obstetric guidance on fish in pregnancy focuses on balance — fish is nutritionally beneficial, and the goal of mercury guidance is to manage risk from specific species while still eating fish overall.

Your prenatal checkups (held roughly every 4 weeks before 23 weeks, and more frequently in later pregnancy) include regular blood tests that can flag nutritional concerns. See our article on prenatal checkups and the Maternity Handbook for more on what to expect at each visit.

11. FAQ

I ate sushi before I knew I was pregnant. Should I be worried?

A single meal of raw fish before you knew you were pregnant is very unlikely to cause harm to your pregnancy. Listeria infection from fish is uncommon, and the early weeks of pregnancy — before the placenta is fully formed — involve different considerations than later trimesters. If you have any specific concerns, mention them at your next prenatal checkup. Avoid seeking diagnosis or reassurance from general information — your obstetrician is the right person to assess your individual situation.

Is it safe to eat at conveyor belt sushi (kaiten-zushi) while pregnant?

It is possible to eat at kaiten-zushi restaurants while pregnant by choosing cooked, non-raw options. Common choices include tamago (egg, cooked), inari, ebi (shrimp, typically blanched), anago (conger eel, cooked), and kappa-maki or other vegetable rolls. The staff will generally be understanding if you explain you are pregnant.

Can I drink Japanese green tea during pregnancy?

Green tea contains caffeine. Sencha and other common Japanese green teas contain approximately 20 mg of caffeine per 100 mL — considerably less than coffee. Many pregnant women in Japan continue to drink moderate amounts of green tea. Some choose to switch to mugicha (barley tea), which is naturally caffeine-free. The amount that is appropriate for you is best discussed with your obstetrician based on your overall caffeine intake from all sources.

Is miso soup safe during pregnancy?

Miso soup is generally considered safe and nutritious during pregnancy. One note: miso paste contains salt, so if your doctor has advised you to monitor your sodium intake (common if you have gestational hypertension or are at risk), be mindful of portion size. Most women eat miso soup without any concern.

What about soba and udon noodles?

Both soba and udon are generally fine during pregnancy when cooked and served hot. Soba contains gluten (from buckwheat, which naturally has some gluten) and is often mixed with wheat flour in Japan — relevant only if you have celiac disease or gluten sensitivity. No pregnancy-specific concerns apply to ordinary cooked soba or udon.

My cravings are making it hard to eat well. What should I do?

Appetite changes, food aversions, and cravings are normal during pregnancy. If you are having difficulty eating a balanced diet — particularly in the first trimester when nausea is common — speak with your midwife or obstetrician. They can offer practical guidance specific to your situation and, if needed, refer you to a registered dietitian.

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