In Japan, Largely Unregulated Compared with Other Developed Countries — Everyday Trans-Fat Foods You Should Definitely Avoid

Trans fats are common but hard to see — first, know the difference

You may have heard the term "trans fatty acids," but many people aren’t sure exactly what they are. The trans fats we encounter in daily life fall into two main categories: "naturally occurring" and "industrial (artificial)." Naturally occurring trans fats are found in the meat and dairy of ruminant animals like cows and sheep and include conjugated linoleic acid (CLA), which has some positive health reports. By contrast, industrial trans fats are created when liquid vegetable oils are partially hydrogenated to make them solid, and these have been linked to health risks. Below we outline those differences, which foods to avoid, and practical countermeasures in an easy-to-understand way.

Risks and evidence associated with industrial trans fats

Association with cardiovascular risk

Industrial trans fats have been reported to worsen lipid profiles by raising LDL ("bad") cholesterol and lowering HDL ("good") cholesterol, which is associated with an increased risk of coronary artery disease. In response to epidemiological studies and public health recommendations overseas, many countries have moved to reduce and regulate industrial trans fats.

Relation to glucose metabolism and inflammation

Diets high in trans fats may also be associated with impaired glucose metabolism and chronic inflammation. The WHO recommends keeping intake of industrially produced trans fats as low as possible, ideally below 1% of total energy intake.

The situation in Japan and why trans fats are "hard to see" — differences in labeling and regulation

In Japan there isn’t the same nationwide legal regulation or uniform labeling requirement as in some Western countries, and declaring trans fat content is generally voluntary. The Ministry of Agriculture, Forestry and Fisheries and the Food Safety Commission have published survey data, but when you look at ingredient lists on supermarket processed foods you often only see terms like “vegetable oils/fats” or “margarine,” making it difficult to tell whether industrial trans fats are present. We’ve been surprised ourselves by someingredient labels, and if we don’t consciously avoid certain products we can end up consuming trans fats without realizing it.

Which foods tend to be high, and how to spot and avoid them in daily life

Typical foods with high content

• Shortening and margarine (processed fats)
• Certain baked goods — biscuits, cookies, pies — and some snack foods
• Commercial frying oils and some fast-food fried items (varies by manufacturer)
• Processed creams and some frozen foods or instant noodles that use processed fats

Surveys by the Ministry of Agriculture, Forestry and Fisheries indicate that shortening and margarine can contain high concentrations, but levels vary widely by product.

Shopping and cooking tips

• Check ingredient lists: watch for terms like "partially hydrogenated oils" or "hydrogenated"
• Choose products labeled "trans fat zero" or "reduced trans fat" when available
• Use liquid vegetable oils (olive oil, canola/rapeseed oil, etc.) or butter when possible. Butter contains small amounts of naturally occurring trans fats, but these differ from industrial trans fats
• Reduce the frequency of eating out or buying prepared foods and cook at home so you can control the quality of the oils you use

Our practices and precautions

When the geefee team checked supermarket labels, we felt products listed only as "vegetable oils/fats" deserved careful attention. For example, we once held back from buying a commercial biscuit because its ingredient list included "vegetable oils/fats" and the label did not specify trans fat content. In practice, we avoid products whose ingredients say "partially hydrogenated," and instead choose items explicitly labeled "0g trans fat" or simple, handmade-style snacks with straightforward ingredients, which gives us greaterpeace of mind.

That said, naturally occurring trans fats in meat and dairy are not necessarily something to completely avoid — nutrients from milk and yogurt, such as calcium and protein, are important. The point is balancing "quality" and "quantity."

Conclusion

Trans fats differ between naturally occurring and industrially produced types, and the primary concern is industrial trans fats. Because labeling and regulation in Japan are still incomplete, it’s important to carefully check ingredient lists and avoid over-relying on margarine and shortening in cooking and eating habits. What we can do at the table is choose the types of oils we use and reduce processed foods. Start by making a habit of checking ingredient lists at the supermarket.

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.