Soy Sauce During Pregnancy: Is It Safe? Benefits and Risks

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Written by Gina Wagg BA, Dip.

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Soy sauce is a staple in many Asian dishes and is also used as a table condiment. Because it’s high in sodium and contains a trace amount of alcohol, it’s understandable that pregnant women wonder if soy sauce is safe to eat during pregnancy.

Soy sauce is safe during pregnancy as long as it’s consumed in moderation. Too much soy sauce can be high in sodium. Soy sauce contains alcohol, isoflavones, and heavy metals, which can be harmful to the developing fetus in excessive amounts.

You can enjoy foods that contain soy, at least in moderation. Here, we’ll dive in a little more about its safety. What are isoflavones? Is it normal to crave soy sauce during pregnancy? Read on to find out more.

Is Soy Sauce Safe or Bad During Pregnancy?

Soy sauce is a fermented product made from soybeans, wheat, salt, and water. It’s used as a condiment or seasoning in many Asian cuisines. It’s safe to  consume soy sauce during pregnancy, but only in moderation because:

  • It’s high in sodium 
  • It contains isoflavones
  • It may contain harmful bacteria – but this is rare
soy sauce in white ceramic bowl

Moderation is key when it comes to soy sauce, because it’s high in sodium. A pregnant woman needs about 1500-2300 mg of sodium per day, and soy sauce contains about 1000 mg of sodium per tablespoon. (source: National Library of Medicine). 

This means that just a few tablespoons of soy sauce can easily exceed the daily recommended intake of sodium for pregnant women. Too much sodium intake during pregnancy can lead to high blood pressure and preeclampsia. (source: American Heart Association)

In addition, all soy-based products such as soy milk and soy sauce contain isoflavones. Isoflavones are a type of phytoestrogen, which is a plant-based compound that has estrogen-like effects on the body. 

A study has found that Isoflavones in soy-based products weaken the immune system of pregnant rats and their offspring (Source: American College of Toxicology). However, it should be emphasized here that these were animal, and not human studies.

More research is needed to determine the effects of isoflavones on pregnant women and their developing fetuses. Again, soy sauce in moderation is fine during pregnancy.

Finally, soy sauce may contain harmful bacteria like Listeria monocytogenes that can cause food poisoning. (Source: National Journal of Food Microbiology), though most commercially-made soy sauce out of the bottle will be safe to use, if it’s been stored properly.

You may also have wondered whether homemade soy sauce is better than homemade, or vice versa. 

The safety of store-bought soy sauce is the same as homemade or fermented soy sauce. Whether you’re using homemade or store-bought, you should limit your intake of soy sauce to moderate amounts throughout your pregnancy. 

Although uncommon outside of Asia, If you decide to make your own soy sauce then you should search and follow a recipe from a trusted source, use fresh ingredients, and sterilize all your utensils.

If you’ve not made your own fermented food before, it might be best to wait until your baby is born before starting.

Does Soy Sauce Contain Alcohol?

Soy sauce does contain trace amounts of alcohol. The alcohol content in soy sauce is usually between 0.0004–1.7wt%. (source: Seoul Women’s University). This is a very small amount.

This means that the amount of alcohol in soy sauce is not enough to cause any harm to the developing fetus. For example, Kikkoman’s Naturally Brewed Soy Sauce only contains <2% alcohol by volume. (source: Kikkoman). 

In fact, research from the University of Copenhagen found that 100ml of sauce with 2% alcohol content is so low that “a pregnant woman would also be able to handle it”. That is equivalent to only 2ml of alcohol per serving, and the amount (Source: Journal of Food Chemistry).

You can also try to cook down the soy sauce if you’re using it in a dish, rather than as a condiment  The heat will evaporate the alcohol in soy sauce (source: American Chemical Society)

For more on this, you can read our article on alcohol in food when you’re pregnant.

soy sauce in a bottle

Is Light (Low Sodium) or Dark Soya Sauce Better When You’re Pregnant?

Light soy sauce is a type of soy sauce that has been processed to remove the color and it also has a lower sodium content. Dark soy sauce is made from soybeans that have been roasted longer, which gives it a darker color and a more intense flavor.

Aside from the low sodium content of light soy sauce, there is no difference in the safety of light or dark soy sauce when you’re pregnant. Both are OK in moderation.

However, because dark soy sauce has a more intense flavor, you may want to use less of it. Also, because light soy sauce has a lower sodium content, it may be a better choice for pregnant women who are trying to limit their sodium intake.

Is Soy Sauce Beneficial During Pregnancy? Is It Healthy?

Soy sauce is not usually considered a “healthy” food for pregnant women, but it’s definitely a good option over creamier, heavier sauces. Soy sauce does contain some nutrients that can be beneficial during pregnancy. For example, soy sauce contains small amounts of protein and iron. (source: Food Research International).

Pregnant women need to be sure to get enough protein and iron during pregnancy. Protein is important for the growth and development of the baby, and iron is important for the production of hemoglobin. (source: American Pregnancy Association).

However, since you only need a small amount of soy sauce to get the desired flavor, coupled with the fact it should be eaten in moderation, it’s not practical to consume soy sauce solely for its nutrient benefits.

adding soy sauce to rice noodle

Is It Normal to Crave Soy Sauce During Pregnancy?

Cravings are very common during pregnancy. In fact, about 75% of pregnant women report experiencing cravings. (Source: American Pregnancy Association). Especially if you are craving something salty like soy sauce.

Hormonal changes often cause pregnancy cravings. These changes can cause pregnant women to crave certain foods or flavors. (source: Cleveland Clinic).

So, if you’re pregnant and you find yourself craving soy sauce, there’s no need to worry. It’s normal, and it doesn’t mean that you’re lacking in nutrients. You can safely have soy sauce in moderation if you’re craving it! Read more here on why you might be craving salty foods during pregnancy.

Overall, when it comes to soy sauce and pregnancy, moderation is key! Try using it to flavor food instead of heavy sauces. This will help you enjoy the taste of soy sauce without consuming too much sodium.