Trans fatty acids

Trans fatty acids can be found in some processed vegetable fats used in food manufacturing. They also occur naturally in some animal products, like cheese and meat. Learn more about them and how they can affect your health.

What are trans fatty acids?

Trans fatty acids are formed when liquid vegetable oils are processed so they are partially hydrogenated (hardened) for use in fat spreads, cooking fats, and shortening used in baked goods.

These trans fatty acids are most likely to be found in:

  • butter and margarine
  • crackers and biscuits
  • snack foods
  • fried foods
  • baked goods
  • other processed foods made with partially hydrogenated vegetable oils.

Low levels of trans fatty acids are also found naturally in meat and milk.

Trans fatty acids in foods sold in New Zealand

Food Standards Australia New Zealand (FSANZ) monitoring of trans fatty acids in the food supply showed that New Zealanders get 0.6% of their daily energy intake (kilojoules) from trans fatty acids.

This falls below the World Health Organization (WHO) recommended maximum of 1% of daily energy intake from trans fatty acids.

Effects of trans fatty acids on your health

Foods high in trans fatty acids increase low-density lipoprotein (LDL) – or “bad” – cholesterol levels. This increases the risk of coronary heart disease – which can lead to heart attacks – as well as increasing the risk of stroke. Unlike saturated fats, trans fatty acids also lower the levels of high-density lipoprotein (HDL), the “good” cholesterol.

Are trans fatty acids identified on food labels?

In most cases, the Australia New Zealand Food Standards Code doesn't require manufacturers to declare a product's trans fatty acid content on the nutrition information panel.

Manufacturers need to provide this information if their product makes a nutrition content claim about:

  • cholesterol
  • saturated, polyunsaturated, monounsaturated fats or trans fatty acids, or
  • omega-3, omega-6 or omega-9 fatty acids.

Many New Zealand fat spread manufacturers voluntarily choose to label the trans fatty acid content of their products.

What can I do to reduce harmful fat in my diet?

Follow healthy eating guidelines to eat a variety of nutritious foods and to limit your consumption of saturated fat.

Find out more

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