Food Spotlight: Notorious Natto

If you haven’t yet tried natto, I hope this post will urge you to consider it.  Known for its slimy, sticky consistency and its distinct aroma, natto contains a range of bioactive compounds that make it a nutritional powerhouse.  Some argue that natto is the healthiest food in the world.  From nattokinase to isoflavones, vitamin K2 and biogenic amines, this fermented delight delivers!

Natto is made from soybeans that are fermented by the bacteria, Bacillus subtilis.  Macronutrients in natto include protein, fat, and carbohydrates.  Micronutrients include vitamin C, iron, potassium, calcium, manganese, copper, zinc, selenium.  Most of the fats in natto are polyunsaturated.  Plus, natto is a great source of fiber.

News to Use: Natto’s Therapeutic Potential

  1. Heart and blood vessel health

Nattokinase is an active ingredient in natto that has been shown to thin blood, help dissolve blood clots (fibrinolytic), and reduce blood pressure.  The polyunsaturated fats in natto have also been shown to improve cholesterol levels.  Note: if you are currently taking blood thinners (such as Warfarin or Eliquis), you should discuss with your doctor the appropriate frequency/quantity of natto for you.  

  1. Gut health

Add natto to your fermented food rotation and for good reason!  As we continue to learn more about the importance of the microbiome (the ecosystem of bacteria, yeast, and viruses that live in our large intestine), the more we realize that diversity matters.  Rotating a variety of fermented foods exposes the gut to more variations of bacterial information which sends a variety of constructive signals to our immune system.  

  1. Bone health

Many of us think of calcium and magnesium for healthy bones, but don’t forget vitamin K (especially vitamin K2 also known as menaquinone-7) which activates proteins that help build and maintain bone mass.  K2 has been shown to reduce the risk of bone fractures and slow age-related loss in bone mineral density.  Natto is the richest food source of vitamin K2 available.  One tablespoon of natto contains 150 micrograms of vitamin K2.  That is about twice the recommended intake.  Hooray for natto!

  1. Immune health

The probiotic-rich profile of natto contributes to its benefits on healthy gut flora which in turn supports your immune system.  Natto is also rich in vitamin C, iron, zinc, selenium, and copper which help to decrease oxidative stress and modulate inflammation.  

  1. Metabolic health

Soy isoflavones have been shown to decrease lipogenesis and adipogenesis while also increasing lipolysis (ie: less fat storage, more fat burning).  

Tips for enjoying natto:

  1. Choose organic/non-GMO natto. 
  2. Beware of the sauce packets included with your natto.  Unfortunately, the sauces included with traditional natto usually have MSG and gluten.  Consider tossing those sauce packets and substituting your own soyu (soy sauce) or tamari (gluten free soy sauce) and natural wasabi.  For a change up, there are some spicy yuzu sauces that when added to natto give it a nice citrus profile.  Don’t forget to add in some chopped green onion or oroshi daikon (raw grated daikon) for that little extra flavor and nutritional pop. 
  3. The gooier the better.  Why fight it?  Consider slicing some okra and yama imo (mountain yam) and adding it to your natto.  These slimy foods make a delicious combination.
  4. Ika and natto.  Make it a full meal.  Slice up some ika (squid), mix with natto, and top it off with some cut shiso leaf.  With rice or without, this combination is delicious!    
  5. A little goes a long way!  It is true that natto is an acquired taste.  But remember, natto is such a nutrition powerhouse that even if you need to hide it in a sushi roll, you are getting bang for your buck!  
  6. Have fun exploring with natto.  There are a lot of natto recipes floating around out there.  I have seen natto pizza, natto pasta, even natto curry.  The sky’s the limit for how you want to enjoy your natto.  But don’t feel bad if you’re a natto traditionalist (like me), enjoying natto as a simple side dish also does the trick.
  7. Budget friendly.  Natto probably delivers the greatest nutrition to cost value.  It usually costs around $3-5 and comes with 3-4 small packages.  That’s around $1.50 per serving.  Now that’s a happy meal!
  8. Freezes well.  Stock up when your favorite natto is on sale so you can always have some on hand.  
natto and ika
natto and ika
natto and okra
natto and okra

A comment on the “soy conundrum.”  Soy has become a controversial topic and is a good example of what happens when we diverge from nature’s original packaging to processed and genetically modified versions.  Remember, food is information.  When we adulterate the packaging, the information of that food changes.  GMO versions of soy in processed proteins, soybean oil, soy lecithin and soy milk communicate very different nutritional messages from their fermented soybean counterparts.  Natto that is produced in a way that honors the traditional wisdom of original packaging and process, delivers a much different story to your cells as a result.  

Natto on my friends!  

From my shopping cart to yours,

Dr. Gesik 

Whether you like natto or not, Dr. Gesik can help you learn how to use food as medicine to help you reach your optimal health potential. IMUA Orthopedics, Sports & Health features personalized Functional Medicine and is located in the Medical Arts Building – Kamalani Tower at 1010 South King Street, Suite 401, Honolulu, HI 96814


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Nagata C, Wada K, Tamura T, Konishi K, Goto Y, Koda S, Kawachi T, Tsuji M, Nakamura K. Dietary soy and natto intake and cardiovascular disease mortality in Japanese adults: the Takayama study. Am J Clin Nutr. 2017 Feb;105(2):426-431. doi: 10.3945/ajcn.116.137281. Epub 2016 Dec 7. PMID: 27927636.

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