A Dentist Who Emphasizes Diet Teaches! Do You Know Foods Rich in Iron? How to Efficiently Supplement Iron Without Relying on Supplements?

The Truth About Iron, Taught by a Dentist Who Emphasizes Diet

Our geefee team has repeatedly felt the importance of "regulating iron through diet" in dental clinics and nutritional guidance settings. Anemia can lead to fatigue and shortness of breath, and can also affect oral health. Before relying on supplements, let's first look at how to improve your diet and gut environment to efficiently supplement iron.

Differences Between Heme Iron and Non-Heme Iron, and Tips for Absorption

Understanding the Differences Roughly

Iron comes in two types: "heme iron" (iron bound to protein), which is abundant in animal products, and "non-heme iron" (iron in an ionic state), which is abundant in plant products. Heme iron has a higher absorption rate, while non-heme iron is less easily absorbed, so the amount taken into the body can vary significantly even if the same amount is consumed. The Ministry of Health, Labour and Welfare's Dietary Reference Intakes (2015 edition) indicates recommended amounts for adults (approximately 10.5 mg for adult women, 7.5 mg for adult men).

Foods that Aid or Hinder Absorption

• Foods that aid absorption: Vitamin C (citrus, strawberries), animal protein (meat, fish), etc. Even non-heme iron's absorption significantly increases when taken with vitamin C.
• Foods that hinder absorption: Tannins found in tea and coffee, phytic acid in grains and beans, oxalic acid in spinach, and calcium-rich foods. Avoid consuming these before or after iron-rich meals.

Main Iron-Rich Foods and Practical Recipe Tips

"Iron-Rich Foods" Ranking (Representative Meat Examples)

Based on data from the Standard Tables of Food Composition in Japan, we introduce representative meat products with high iron content (per 100g, approximate).

• Pork Liver: 13.0 mg
• Chicken Liver: 9.0 mg
• Raw Senmai (beef tripe): 6.8 mg
• Chicken Hearts: 5.1 mg
• Duck Meat / Horse Meat: 4.3 mg (each)
• Beef Liver: 4.0 mg

Organs (such as liver and hearts) are "blood-rich parts" and are abundant in iron. Conversely, be aware that common red meats and white meats do not contain as much iron as organ meats.

Cooking Tips to Make it Easier to Eat (Methods We Found Effective)

• Blanch liver to remove blood, then use onions or milk to remove any odor. After that, purée it and serve on baguettes or in sandwiches to make it easier to eat. We tried this, and it made it more palatable even for children and those who dislike liver.
• Use seafood (dried sardines, sardines, clams, etc.) as a main dish or in broth. Cooking small fish whole, including bones, increases their nutritional value.
• Leafy greens like spinach, when combined with vitamin C-rich ingredients (lemon or citrus), increase absorption. However, spinach is susceptible to oxalic acid, so try cooking it with oil.

Before Relying on Supplements: Gut Environment and Safety Precautions

Reasons to Improve Your Gut Environment

Many people have experienced black stools or an upset stomach after taking iron supplements. While black stools are generally due to the color of iron, unabsorbed iron remaining in the intestines can feed bad bacteria and H. pylori, potentially worsening the gut environment. In our clinical experience, the quickest way to improve was to first adjust dietary habits and regulate gut flora with fermented foods and dietary fiber.

Supplement Risks and the Need for Doctor Consultation

• Many iron preparations in medical institutions are non-heme iron (inorganic salts like ferrous sulfate), which can often cause gastrointestinal symptoms.
• Excessive iron intake has been suggested to increase the risk of infection and oxidative stress. Avoid continuing supplements without careful consideration, and use them based on tests (blood tests, ferritin measurements) and a doctor's guidance.
• If you experience black stools, it is important to determine whether it is supplement-related or due to gastrointestinal bleeding. If you have any concerning symptoms or signs of anemia (palpitations, dizziness, pica, etc.), please consult a medical institution.

Specific Habits You Can Adopt Daily to "Improve Iron Absorption"

• Combine liver paste, small fish tsukudani, and citrus fruits for breakfast.
• Avoid coffee and green tea immediately after meals; leave a 1-hour gap before and after eating.
• Aim for meals where animal protein (meat, fish, etc.) is the main dish, and vegetable vitamin C supports non-heme iron absorption.
• Reduce processed foods, excessive sugar, and unhealthy fats, and increase fermented foods (natto, yogurt, pickles, etc.) and dietary fiber to improve your gut environment.
• Pregnant individuals should be cautious about excessive liver intake (liver is rich in vitamin A (retinol), and excessive intake may affect the fetus).

Summary

Iron is not something where "simply consuming a lot is good"; how it is consumed and how it is combined with other foods is very important. Liver and seafood, which contain heme iron, are efficient sources of iron, but certain individuals, such as pregnant women, need to be careful about their intake. From what we see clinically, it is safe and effective to first review your diet and improve your gut environment, and if deficiencies persist, consult a doctor to consider supplements or medication. With a little daily effort, it is entirely possible to naturally supplement iron without relying on supplements. Please try it starting with today's meals.

Disclaimer: The information in this article is for general informational purposes only and does not constitute medical advice. Please consult a qualified healthcare professional before making any health-related decisions.