Dietary fats refer to a group of fatty acids that vary significantly in their structure and nutritional properties, as well as their roles and responses in the body.
All fats provide 9kcal per gram, in comparison to carbohydrates that contain 3.75kcal per gram, protein that contains 4kcal per gram and alcohol which contains 7kcal per gram.
Dietary fats are generally grouped into two main types:
- Unsaturated fats
- Monounsaturated fats
- Polyunsaturated fats
- Saturated fats
Another group of unsaturated fats includes trans fats, which are predominantly created during the production of margarines, fat spreads, and processed foods. These fats are thought to have a number of adverse effects on the body and the development of many disease states, and therefore consumption should be kept to a minimum.
Why are fats important?
Dietary fats play a number of important roles in the body, making them an essential component of the diet. Such roles include:
- A source of energy, particularly at rest and during low intensity exercise
- The development and maintenance of health of the central nervous system and brain tissue
- The absorption of fat soluble vitamins such as the vitamins A, D, E and K
- The production of hormones such as testosterone and oestrogen, amongst others
- A major structural component of all cells in the body
Which fats should I eat?
Fats should be consumed on a daily basis to optimise health and nutritional status; however, care should be given to the overall volume of such foods depending on personal energy requirements and physical goals, the types consumed, and the way food has been cooked/prepared.
As with all foods there are ‘good’ and ‘bad’ varieties, based on the impact they have on the body when consumed. Saturated fats found in coconut oil, nuts, seeds and other foods that are naturally occurring, are indeed good for us, versus the saturated fats consumed through heavily processed foods and deep fat fried foods that can have a negative impact on health.
Cooking and preparation:
The structure of a fat can be altered when cooking and during food manufacturing processes. For example, extra virgin olive oil in its unheated state e.g. when added to salads as a dressing, is a great source of monounsaturated fats and antioxidants. However, these fats and antioxidants are easily damaged when exposed to heat, and therefore shouldn’t be used for cooking. Coconut and rapeseed oil are much more resistant to damage at high temperatures and are therefore preferential to cook with.
Fats are an important component of the diet. Choose good quality sources such as oily fish, avocados, olives and olive oil, coconut and coconut oil, nuts and seeds to ensure you get the correct types of fats. Just be mindful of how much you consume and your overall energy requirements if you have specific body composition and weight goals.