Miso

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By Nikola · Precision Nutrition L1 · Updated 5 November 2026

Miso is a thick, salty paste made from fermented soybeans, often with rice or barley, and it is the base of Japanese miso soup. A little goes a long way: one tablespoon (17 g) has about 34 kcal and 2 g of protein, but also 634 mg of sodium, which is 1.6 g of salt or roughly a third of the daily limit the World Health Organization recommends. Used as a seasoning instead of plain salt, miso adds a deep, savoury flavour to soups, dressings, marinades and vegetables. It contains soy, one of the allergens that must be declared on EU food labels.

Miso nutrition per 100 g and per tablespoon

Nutrient	Miso, 100 g	1 tablespoon, 17 g
Energy	198 kcal	34 kcal
Protein	12.8 g	2.2 g
Fat	6.0 g	1.0 g
Carbohydrate	25.4 g	4.3 g
of which sugars	6.2 g	1.1 g
Fibre	5.4 g	0.9 g
Sodium	3730 mg	634 mg
Salt (sodium × 2.5)	9.3 g	1.6 g
Vitamin K	29.3 µg	5.0 µg
Zinc	2.6 mg	0.44 mg
Manganese	0.86 mg	0.15 mg
Copper	0.42 mg	0.07 mg
Potassium	210 mg	36 mg

Source: USDA FoodData Central, SR Legacy: “Miso” (FDC 172442), checked 5 November 2026. The 17 g tablespoon is a USDA portion; the portion column is calculated. Salt is calculated with the EU formula salt = sodium × 2.5 (Regulation (EU) No 1169/2011, Annex I). The record does not say which type of miso was analysed; light and dark misos, and reduced-salt products, can differ a lot, so compare labels. Values rounded.

Glycemic index

Miso is not listed in the international GI tables (Atkinson 2008). It is eaten in small amounts, about 4 g of carbohydrate per tablespoon, so for blood sugar the portion of rice or noodles served with it matters far more.

Health benefits: what the evidence says

• Flavour with less added fat. Miso brings a lot of savoury taste for 34 kcal a tablespoon, which makes vegetable soups, dressings and glazes satisfying without much oil or butter.
• A soy food. NCCIH lists miso among common soy foods together with tofu, tempeh, edamame and soy milk. The evidence NCCIH describes for soy, such as a small cholesterol-lowering effect when soy protein replaces other proteins, comes mostly from larger amounts of soy than a spoon of miso provides, so do not expect miso to have the same effect.
• Some fibre and minerals. Per 100 g miso has 5.4 g of fibre and useful zinc and manganese, but at a tablespoon these amounts are small.

Miso is often promoted for gut health because it is fermented. Solid evidence for miso itself is limited, and the best-documented fact about it is its salt content.

How to eat it

• Miso soup: heat stock or water with vegetables, small cubes of tofu and seaweed. Take the pot off the heat, dissolve the miso in a ladle of hot liquid and stir it back in. Miso is traditionally added at the end rather than boiled hard.
• Measure, do not eyeball: one level tablespoon is plenty for a large bowl. Do not add extra salt.
• Dressing: whisk 1 teaspoon of miso with lemon juice, sesame or tahini and a little water for salads and grain bowls.
• Glaze: brush roasted aubergine, pumpkin or salmon with miso mixed with a little honey and ginger.
• Replace salt: a teaspoon in a lentil or mushroom stew gives depth, so you need less salt elsewhere.
• Storage: keep opened miso tightly closed in the fridge.

Who should be careful

• High blood pressure and salt limits. WHO recommends that adults eat less than 2000 mg of sodium a day (less than 5 g of salt), and calls excess sodium a well-established cause of raised blood pressure and increased risk of cardiovascular disease. One tablespoon of miso gives about 32% of that sodium limit. If you follow a DASH diet or a low-salt plan, count miso as salt.
• Soy allergy. Soy is a declared allergen in the EU, and MedlinePlus lists it among the most common food allergies, mostly in children.
• Coeliac disease. Some miso is made with barley, and Coeliac UK lists barley as not gluten free. Check the ingredients or choose miso labelled gluten free.
• MAO inhibitor antidepressants. NCCIH reports interactions between monoamine oxidase inhibitors and certain soy products that contain high amounts of tyramine. If you take such a drug, ask your doctor whether miso and other fermented soy foods are safe for you.

Traditional view (Ayurveda)

In Usha and Vasant Lad’s food guidelines, miso is okay rarely for Vata and best avoided by Pitta and Kapha. This is a traditional view, not a clinical finding.

Related entries and articles

• Tofu – the classic partner in miso soup
• Edamame – whole young soybeans
• Sauerkraut – another fermented food
• Mushrooms
• DASH diet – for keeping sodium in check
• Natural remedies for better digestion

FAQ

How much salt is in miso?

About 9.3 g of salt per 100 g, or 1.6 g in a 17 g tablespoon, based on the USDA sodium value of 3730 mg per 100 g. Reduced-salt misos exist, so compare the salt line on the label.

Is miso gluten-free?

Not always. Miso made only from soybeans and rice does not contain gluten grains, but some miso is made with barley, which contains gluten. If you have coeliac disease, read the ingredients and look for a “gluten free” label.

Should you boil miso?

Miso is traditionally stirred into the soup at the end, off the boil, which keeps its aroma. Dissolve it in a ladle of hot liquid first so it mixes evenly.

Sources

1. USDA FoodData Central, SR Legacy: Miso (FDC 172442). fdc.nal.usda.gov
2. WHO fact sheet: Sodium reduction (2026). who.int
3. NCCIH: Soy. nccih.nih.gov
4. Coeliac UK: Grains. coeliac.org.uk
5. MedlinePlus Medical Encyclopedia: Food allergy. medlineplus.gov
6. Regulation (EU) No 1169/2011, Annex I (salt formula) and Annex II (allergens). legislation.gov.uk
7. Atkinson FS, Foster-Powell K, Brand-Miller JC. International Tables of Glycemic Index and Glycemic Load Values: 2008. Diabetes Care 2008;31(12):2281-2283. PMC
8. Lad U, Lad V. Food Guidelines for Basic Constitutional Types, from Ayurvedic Cooking for Self-Healing, 2nd ed. The Ayurvedic Institute. ayurveda.com

This page is for information only and is not medical or dietary advice.