One part of eating for a healthy heart and brain is eating more foods that contain unsaturated fats (like nuts, seeds, avocado, healthy oils, oily fish), and less foods that contain saturated fats (animal fats).
What are fats and why are they important?
Fats are a group of compounds that make an important contribution to our nutrition, despite their bad press. Fats are major sources of energy and the only way in which the body can store energy for a long period of time. Fats also:
- help control body temperature
- give some protection to internal organs
- supply essential fatty acids (those that can’t be made by the body)
- make up the structure and function of cell membranes
- ensure absorption of the fat-soluble vitamins
- fill us up
- make some foods taste better.
Getting the right balance of how much and what type of fat to eat is important. It's better for our heart and our brain to eat plant-based fats and oils (except coconut and palm oils) instead of animal-based fats and oils, ie, butter and meat fat.
What happens when we eat too much of the wrong type of fats?
- Too much fat can cause us to gain weight especially if you don't exercise enough, even if you choose the ‘healthy’ fats.
- Eating too much saturated fat and trans fats (see information at bottom of this page), can increase cholesterol levels and our risk of heart disease and a number of other diseases. With nearly one quarter of New Zealanders having high cholesterol, we need to start changing the type of fat we eat.
- A typical New Zealander’s diet contains around 35% of total energy as fat, whereas the goal is 20-25% and our saturated fat intake is 15% of total energy, instead of 12%.
- Remember, we all need some fat in our diets – so it’s best to choose the healthy ones!
These are considered the ‘bad’ fats because of their link to heart disease and should be eaten in small amounts. They come mostly from animal products, especially fatty meats, and dairy products, like butter, full-fat milk and cheese, but also from coconut and palm oil. Fast foods are also major contributors.
Eating saturated fat increases both good (HDL) and bad (LDL) cholesterol levels. Controlling your LDL cholesterol level is the best-known way of lessening your risk of coronary heart disease, so eating fewer of the foods that contain large amounts of saturated fat is an important way to do this.
We don’t need these fats in our diet at all. Although they are unsaturated, when food manufacturers 'hygrogenate' them to make them firm, they become more like saturated fats in their effects on blood cholesterol. Not only do they increase our levels of bad (LDL) cholesterol, but they also decrease our levels of good (HDL) cholesterol.
Mostly these fats come from manufactured foods, like some margarines and peanut butters, biscuits, crackers, cakes and potato chips. However, most spreads now available in New Zealand and Australia only contain a small proportion of trans fats.
Check food labels to see if what you are buying contains trans fats.
These are often referred to as the ‘good’ fats as they don’t have the same effect on blood cholesterol levels as saturated and trans fats. As a result, they are not as much of a concern to our health as they don’t increase the risk of heart disease. They are still a type of fat and all fats when eaten in quantities greater than our bodies need can lead to weight gain.
Unsaturated fats include monounsaturated and polyunsaturated. Omega-3 fats are a type of polyunsaturated fat.
Food sources of saturated and unsaturated fats
Almonds and almond oil
More about saturated fat and trans fats Heart Foundation
Food and nutrition guidelines Ministry of Health
Eating a health and balanced diet at different stages of life HealthEd