Japanese Traditional Food Analysis Series Part 2 - geefee's Worst 4 Recommended Japanese Foods

Introduction: Traditional "Good Foods" Can Become Points of Caution in Modern Health Knowledge

Last time, we presented our "Top 4 Healthy Japanese Foods," but this time, we'll cover the "Worst 4 Japanese Foods" that you should be cautious about. Japanese cuisine is globally acclaimed, but depending on ingredient processing methods and modern distribution, old wisdom may not always apply. We were often surprised by our research and actual tests, and honestly, there was a lot of information we felt "glad to know." Here, we'll focus on the risks and practical measures you can take in your daily life.

Bonito Flakes: The Risk from Smoke Behind the Umami

Bonito flakes are essential to dashi culture, but reports indicate that carcinogenic substances like polycyclic aromatic hydrocarbons (PAHs), especially benzo[a]pyrene, can be introduced during the smoking and heating processes. The Ministry of Agriculture, Forestry and Fisheries' research also detected benzopyrene in samples, and in the EU, the standard for smoked fish is set at 5 μg/kg, meaning products exceeding this standard may be subject to import restrictions. In Japan, however, there isn't a clear, equally strict standard, so consumers need to be cautious.

Solution Point!

A practical measure is to avoid frequent, large consumption and choose reliable producers or manufacturers who disclose low-temperature, short-duration processing methods. Additionally, you can reduce intake by combining umami from kombu dashi and dried shiitake mushrooms instead of relying solely on bonito flakes. When we tried it, using half kombu and half bonito flakes maintained dashi satisfaction.

Fried Foods (Tonkatsu, Tempura, Karaage, etc.): Oxidized Lipids, AGEs, and Harmful Substances from Cooking

High-temperature frying is a cooking method that easily produces substances harmful to health, such as oil oxidation, trans fats, oxidation products, and additionally, heterocyclic amines and polycyclic aromatic hydrocarbons formed during cooking. Epidemiological studies have also reported a correlation between a diet high in fried foods and an increased risk of certain cancers. Furthermore, the reuse of oil in restaurants and convenience stores is a problem, as it tends to promote oxidation.

Solution Point!

While completely eliminating fried foods is ideal, if difficult, reduce frequency and devise cooking methods. Avoid short-duration high-temperature cooking over slow, low-temperature frying, thin the batter, thoroughly drain oil after frying, and at home, use monounsaturated fatty acid oils resistant to oxidation (such as macadamia nut oil, high-oleic oils, or avocado oil) to reduce oxidative damage. Our tests showed that "fried-style" dishes made with an air fryer or oven maintained satisfaction while reducing harmful substances. When eating out, it's also effective to track the frequency of fried foods and decide on a "maximum number of times per week."

Sushi and Sashimi of Large Fish: Beware of Methylmercury Accumulation

Large, long-lived fish such as tuna, yellowtail, and swordfish tend to accumulate methylmercury through the food chain, and there are concerns about its effects, especially on pregnant women and infants. Fish is a good source of protein and has many benefits, such as omega-3 fatty acids, so it's n