The Consumer Affairs Agency said Friday it plans to ask manufacturers of margarine and other foodstuffs to voluntarily disclose by year's end the amount of trans fat, if any, in their products to reduce the risk of cardiac disease.

The agency revealed the plan in draft guidelines for the voluntary disclosure of levels of trans fatty acids in food products. Trans fatty acids are believed to increase low density lipoprotein cholesterol, known as "bad cholesterol," and thus the dangers of cardiovascular disease.

While food makers in Japan are not currently required to disclose the amount of trans fat in their products, disclosure is now mandatory in the United States and many other countries.

The guidelines, to be formalized by year's end, call for indicating on the label the gram-based amount of trans fats per 100 grams or per meal.

The agency is also considering legislation to make this kind of food labeling mandatory.