How Often Should You Eat Natto Beans?

January 14, 2026 •

4 min read

In Japan, a long-term study involving 92,000 individuals found that those who consumed around 1.8 ounces of natto daily had a significantly lower risk of cardiovascular disease. This powerful statistic highlights why many wonder how often should you eat natto beans to maximize its health benefits without overdoing it.

Quick Summary

This guide explores the optimal frequency for consuming natto, considering daily versus weekly intake, recommended serving sizes, and the potential health benefits for heart, bone, and gut health.

Key Points

Daily Intake: A small portion, like one tablespoon, provides a steady supply of vitamin K2 and nattokinase for consistent health benefits.
Weekly Intake: Eating natto several times a week is also effective and traditionally common, a good option for newcomers to adapt to its unique taste.
Serving Size: A standard serving is typically a 40-50 gram pack, often sufficient for a day's intake.
Heart Health: Natto contains nattokinase, an enzyme that acts as a natural blood thinner and may support heart health by dissolving blood clots.
Bone Health: Exceptionally rich in Vitamin K2, natto helps direct calcium to bones, which is crucial for bone mineral density and fracture prevention.
Gut Health: As a probiotic-rich food, natto supports a healthy gut microbiome and aids in digestion.
Medical Caution: Individuals on blood-thinning medication should consult a doctor due to natto's anticoagulant properties.
Versatile Preparation: Natto can be enjoyed in various ways beyond its traditional serving with rice, including in soups, with eggs, or on toast.

Optimal Natto Consumption: Daily vs. Weekly

Natto, a traditional Japanese food made from fermented soybeans, is packed with potent nutrients like Vitamin K2 and nattokinase. The frequency of consumption can be adapted to individual health goals and tolerance. Historically, natto is eaten in small portions several times per week in Japan, while some modern studies and recommendations point to the benefits of daily intake.

For those new to the unique taste and texture, starting with small, weekly servings is a gentle approach. As your palate and digestive system adjust, you can gradually increase frequency. Consuming a small portion, such as one teaspoon to one tablespoon, daily is generally considered sufficient for most healthy individuals to provide a steady supply of nutrients. For those with specific health goals, such as maximizing Vitamin K2 intake, daily consumption may be preferred.

The Health Benefits of Consistent Natto Intake

The health advantages of natto stem from its unique fermentation process using Bacillus subtilis bacteria. This process produces the powerful enzyme nattokinase and a highly absorbable form of Vitamin K2 (menaquinone-7).

Supporting Cardiovascular Health

Nattokinase has been shown to have fibrinolytic activity, meaning it can help dissolve blood clots and potentially improve blood flow. Regular consumption of natto is linked to lower rates of death from heart-related illnesses. In addition, the high Vitamin K2 content helps prevent arterial calcification by ensuring calcium is directed to bones instead of building up in arteries.

Promoting Bone Health

Vitamin K2 is essential for bone development and maintaining bone mineral density. Studies have shown that a diet rich in Vitamin K2 can reduce the risk of fractures. Regular, steady intake of natto provides this vital nutrient, contributing to stronger bones, especially important for postmenopausal women and those at risk for osteoporosis.

Improving Gut Health

As a fermented food, natto is a potent source of probiotics. The Bacillus subtilis bacteria survive the gastrointestinal tract, helping to create a healthy gut microbiome. This can lead to improved digestion and a stronger immune system. A balanced gut flora has been linked to numerous health benefits, including better mood and reduced inflammation.

Serving Size and Moderation

Moderation is key, especially for newcomers. A typical serving of natto is a small 40-50 gram pack (about 1.5 to 1.8 ounces), often eaten with rice. Eating one of these packs per day is a common recommendation for consistent benefits. Starting with smaller amounts, like a teaspoon, can help your body adjust to the potent probiotics and unique compounds.

For those seeking to add more probiotics and nutrients to their diet, incorporating other fermented foods can provide variety and additional benefits. Foods like kimchi, sauerkraut, and yogurt can complement natto's unique nutrient profile. The fermentation of natto also breaks down anti-nutrients present in soybeans, making it easier to digest and absorb.

Potential Risks and Who Should Be Cautious

While highly beneficial for most, natto is not suitable for everyone. Its blood-thinning properties require caution for individuals on anticoagulant medications like warfarin. Always consult a doctor before adding natto to your diet in this case. People with soy allergies should avoid natto, and those with impaired thyroid function should be mindful, as soybeans are considered a goitrogen. Side effects for newcomers might include digestive issues like bloating, which often subside as the body adapts.

Incorporating Natto into Your Diet

Incorporating natto doesn't have to be limited to the traditional breakfast with rice. Here is a list of ways to enjoy this nutritious food:

Classic style: Serve over steamed rice with a dash of soy sauce and Japanese mustard.
Added to soup: Stir into miso soup or other broths.
On toast: Spread on toast with avocado for a modern twist.
With eggs: Mix into scrambled eggs or an omelet for extra protein.
In wraps or bowls: Add to a salad, grain bowl, or wrap with other vegetables for a nutrient-dense lunch.
As a condiment: Use as a topping for curry or tofu dishes.

Natto vs. Other Fermented Foods


Feature	Natto	Yogurt	Sauerkraut	Kimchi
Primary Fermenting Microbe	Bacillus subtilis	Lactobacillus, Streptococcus	Lactobacillus	Lactobacillus
Probiotic Type	Spore probiotic	Non-spore probiotic	Non-spore probiotic	Non-spore probiotic
Nutrient Standout	Vitamin K2 (Menaquinone-7) & Nattokinase	Calcium & protein	Vitamin C & fiber	Vitamin C & antioxidants
Key Benefit	Heart and bone health	Digestive health	Immune support	Immune support & gut health
Source	Soybeans	Dairy (or plant-based milk)	Cabbage	Cabbage & other vegetables

Conclusion

The optimal frequency for eating natto beans varies based on individual health needs and preference, but a small portion, approximately one teaspoon to one tablespoon, daily is a good starting point for most healthy people. This consistent intake can support significant health benefits, including improved heart, bone, and gut health. For those on blood thinners or with soy allergies, it is essential to consult a healthcare provider. Incorporating natto into your diet regularly, whether daily or several times a week, is a powerful way to enhance overall well-being. To learn more about the unique benefits of natto, consider visiting the National Center for Biotechnology Information (NCBI) for research articles like this one: Natto: A medicinal and edible food with health function.

Frequently Asked Questions

Yes, for most healthy people, it is safe to eat a small portion of natto daily. Many Japanese people consume it regularly as part of their diet. However, those on blood thinners or with specific health conditions should consult a doctor first.

A common recommended serving size is one small 40-50 gram package, which is often eaten with a bowl of rice. For newcomers, starting with just a teaspoon or tablespoon is recommended.

Natto can be enjoyed at any time. Eating it for breakfast, as is traditional in Japan, can boost metabolism and circulation. Having it for dinner may support skin repair and overnight recovery.

Yes, as part of a balanced diet. Natto is high in protein and fiber, which promotes a feeling of fullness. Additionally, a healthy gut microbiome, supported by probiotics in natto, has been associated with weight management.

The nattokinase enzyme, beneficial for heart health, can be sensitive to high heat. While natto can be added to warm dishes, it is best to consume it raw or add it at the end of cooking to preserve the enzyme's activity.

For most, the main risks are related to its blood-thinning effects if combined with anticoagulant medication. Some people may also experience initial bloating or gas due to the high probiotic content.

Absolutely. Natto is one of the richest food sources of Vitamin K2, which plays a crucial role in directing calcium to the bones and maintaining bone mineral density.