Hannah Ebelthite is a freelance health, fitness and wellbeing writer. With nearly two decades experience in journalism, she has held staff posts on Cosmopolitan, Zest and Healthy magazines, and writes for a wide range of...

There are three major types of fat: saturated, monounsaturated and polyunsaturated fats, each made up of units known as fatty acids. Most foods contain a mixture of fats but are categorised according to the type found in the largest amount. Olive oil is often referred to as a monounsaturated fat, for example, but it also contains smaller amounts of saturates and polyunsaturates.

Saturated fats

These are generally solid at room temperature and are linked to increasing levels of total and LDL or bad cholesterol in the blood, increasing the risk of heart disease. Most commonly – but not exclusively – found in significant amounts in animal products.

• fatty meat
• chicken skin
• processed meat
• full-fat milk, cheese and yogurt
• cream
• ice cream
• butter, lard or dripping
• palm oil
• ghee
• cooking/baking margarine
• deep-fried foods
• baked goods (such as cakes, pastries, pies and biscuits)
• coconut (including cream, oil and milk)

Polyunsaturated fats

Polyunsaturates tend to be liquid at room temperature and may help to lower total and LDL cholesterol (but may also lower HDL or good cholesterol). They can be divided into two groups – omega-3 and omega-6. Both are important for heart health but omega-3s also help to reduce inflammation and are important for cognitive function. Although our bodies can make omega-3 fats from plant foods such as seeds, nuts and vegetable oils, the best ‘ready made’ source is oil-rich fish.

• polyunsaturated margarine
• sunflower oil, seeds and spread
• flaxseed (linseed) oil and seeds
• safflower oil
• maize oil
• corn oil
• sesame oil
• soybean oil and soya spread
• pumpkin seeds
• sesame seeds
• walnuts
• pine nuts
• brazil nuts

Monounsaturated fats

These are also usually liquid at room temperature. Health experts agree they’re the healthiest type as they help to lower total and LDL cholesterol but, unlike polyunsaturates, they also maintain levels of HDL or good cholesterol, making them a great choice for a healthy heart.
Olive oil

• olives
olive oil and olive-based spread
rapeseed oil and spread
• avocados and avocado oil
• peanuts, peanut oil and peanut butter

So what are trans fats?

These occur naturally in small amounts in meat and dairy products but are also made when unsaturated fats are altered during processing to increase their shelf life. The resulting processed fats (called hydrogenated vegetable oils or HVOs) are used in a variety of products, such as cakes, biscuits, pastry and fried foods, and act in the same way as saturated fats in the body, increasing LDL cholesterol. But they also reduce HDL cholesterol levels. Trans fats are less of a problem than they used to be as food manufacturers have worked hard in the past decade to remove all HVOs from products, and average intakes in the UK are now well below the recommended maximum. It’s still worth checking the ingredients list, though – you’ll need to look for the words ‘hydrogenated vegetable fats or oils’.

• products that contain hydrogenated or partially hydrogenated vegetable oil (HVO/PHVO)
• shortening
• deep-fried foods
• commercially baked products