Can I eat natto every day? The health benefits
For centuries, natto has been a staple in the Japanese diet, and for good reason. Daily or frequent consumption is associated with a wide array of health benefits that are now gaining global recognition. The key lies in its unique nutritional composition, especially the enzyme nattokinase and high vitamin K2 content.
Heart Health
- Natural Blood Thinner: Nattokinase, the powerful enzyme found in the sticky part of natto, is a natural fibrinolytic agent, meaning it helps dissolve blood clots. This effect promotes healthy blood flow and helps protect against cardiovascular diseases like strokes and heart attacks.
- Lowers Blood Pressure: Some studies suggest that nattokinase can have a blood pressure-lowering effect. This helps reduce the overall strain on the heart and arteries over time.
- Reduces Cholesterol: The fiber and polyunsaturated fats in natto can help manage cholesterol levels, specifically by reducing LDL ("bad") cholesterol, which can prevent plaque buildup in the arteries.
Bone Health
- Rich in Vitamin K2: Natto is a world-class source of vitamin K2 (menaquinone-7), which plays a crucial role in bone health. Vitamin K2 helps the body regulate and transport calcium, ensuring it is deposited in the bones rather than accumulating in arteries, where it can cause calcification.
- Prevents Osteoporosis: Regular intake of natto has been linked to better bone mineral density and a reduced risk of bone fractures, particularly in postmenopausal women.
Gut and Digestive Health
- Potent Probiotic: Fermented by the Bacillus subtilis natto bacteria, natto is a powerful probiotic food. These living microorganisms support a healthy gut microbiome, which can aid digestion, reduce symptoms like bloating and constipation, and strengthen the immune system.
- Increased Nutrient Absorption: The fermentation process helps break down antinutrients naturally found in soybeans, making the vitamins and minerals in natto easier for the body to absorb.
Other Benefits
- Supports Weight Management: With its high protein and fiber content, natto can help promote a feeling of fullness, which can be beneficial for weight management by curbing the desire for unhealthy snacks.
- Improves Immune Function: The probiotics and various vitamins, including vitamin C and zinc, contribute to a robust immune system.
Potential risks and side effects of eating natto daily
While highly beneficial for most, daily natto consumption is not without its considerations, and certain individuals should exercise caution.
- Drug Interactions: The blood-thinning effect of nattokinase and the high vitamin K2 content are important factors for those on anticoagulant medications like warfarin. These individuals should consult a doctor before adding natto to their daily diet, as it can interfere with their medication. Some specialty natto supplements have vitamin K2 removed, but medical consultation is still necessary.
- Hypothyroidism Concerns: Soy is considered a goitrogen, which is a substance that can interfere with thyroid function. Individuals with hypothyroidism may need to limit their soy intake, including natto, or consult their doctor to determine a safe amount.
- Soy Allergies: Natto is made from fermented soybeans, so anyone with a soy allergy should avoid it entirely.
- Digestive Issues: Some people may experience mild digestive upset, such as bloating or gas, especially when first introducing this fiber-rich food into their diet.
- High Purine Content: Excessive consumption could potentially increase uric acid levels, which might pose a risk for individuals prone to gout. However, this is generally more of a concern with overconsumption rather than a small daily portion.
Comparing the pros and cons of daily natto consumption
| Feature | Pros of Daily Natto Consumption | Cons of Daily Natto Consumption |
|---|---|---|
| Heart Health | Reduces risk of heart attack and stroke via nattokinase. | High vitamin K2 content can interfere with blood-thinning medication. |
| Bone Health | Excellent source of vitamin K2 for bone strength. | N/A (no significant bone health-related cons). |
| Gut Health | Provides potent probiotics for a healthy microbiome. | Some individuals may experience gas or bloating. |
| Nutrient Absorption | Fermentation reduces antinutrients, boosting bioavailability. | N/A (no significant nutrient absorption-related cons). |
| Metabolism & Weight | High protein and fiber promote satiety. | Potential for weight gain if portions are too large and calorie intake is not managed. |
Recommended daily portion size and serving suggestions
Traditionally, a small portion of natto, about 40-50 grams (1.5–1.8 ounces), is eaten per day. For most people, this is a safe and effective amount to reap the benefits without potential side effects. In Japan, it is a popular breakfast dish, often served over rice with soy sauce and mustard.
- Breakfast: Serve a 40g pack over hot steamed rice. Stir vigorously to create a frothy, stringy texture before adding condiments.
- Lunch: Mix natto with salad or vegetables for a high-fiber, energizing midday meal that prevents post-lunch drowsiness.
- Dinner: Consume a moderate portion in the evening for skin repair benefits during sleep. Pair with soup or vegetables rather than heavy carbohydrates.
- Alternative forms: For those who dislike the taste or texture, natto powder capsules are an option. Dried natto can also be added to snacks.
Conclusion
For most healthy individuals, eating a small portion of natto daily is not only safe but also a fantastic way to boost overall health, especially for heart and gut function. The concentrated amounts of vitamin K2 and nattokinase provide unique benefits that are difficult to find in other foods. However, the importance of moderation and awareness of potential contraindications—particularly for those on blood thinners or with thyroid issues—cannot be overstated. By being mindful of serving size and consulting a healthcare provider where necessary, you can confidently make this traditional Japanese superfood a part of your daily routine.
Frequently Asked Questions
Q: What is the recommended daily dosage of natto? A: A standard portion is typically one pack, or about 40-50 grams. This provides sufficient nutrients like nattokinase and vitamin K2 without overdoing it.
Q: Who should avoid eating natto daily? A: Individuals on anticoagulant medications, those with a soy allergy, or people with hypothyroidism should be cautious or avoid daily natto consumption.
Q: Does eating natto make your blood too thin? A: The nattokinase in natto has a mild blood-thinning effect. However, for those already on blood-thinning medication, daily intake can increase the risk of bleeding and requires medical supervision.
Q: Is natto safe during pregnancy? A: There is insufficient evidence to confirm the safety of nattokinase supplements during pregnancy. Pregnant women should consult their doctor before regular consumption of natto.
Q: Can natto be eaten at any time of day? A: Yes, natto can be eaten any time. Morning consumption can boost metabolism, midday can enhance focus, and evening intake can aid in tissue repair.
Q: What are the main side effects of eating too much natto? A: Potential side effects from excessive intake include digestive issues like gas and bloating, and an increased risk of gout due to high purine content.
Q: How can I mask the taste and texture of natto? A: Many people mix natto with seasonings like soy sauce and karashi mustard. For beginners, incorporating it into rice, omelets, or even using dried natto or powder can be a good option.
Q: Is the vitamin K in natto bad for your arteries? A: No, the vitamin K2 found in natto is beneficial. It helps direct calcium to the bones and prevents it from calcifying in the arteries, unlike poorly absorbed calcium.
Citations
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