Saturated & Unsaturated Fats
Oil is often the very first cooking ingredient that goes in the pan, they’re great for getting the onion and garlic sizzling, releasing their aromatic flavours whilst preventing the food from burning and sticking. Oil is also often used for frying, roasting, baking and drizzling.
As an essential ingredient in many recipes, what are the differences between them all when it comes to saturated and unsaturated fat content? We take a look and discuss the role of both in terms of their impact on health.
Oil is 100% Fat
Unlike many other foods that are made up of a combination of carbohydrates, protein and fats - oils consist of 100% fat. This means, gram for gram oils are the most energy dense with 9 kcals (kilo calories) of energy per gram of fat. Compared with carbohydrates and protein which have 4 kcals of energy per gram, therefore fats are more than double the energy density.
For example, 1 tbsp (11g) of oil provides 99 kcals of energy and 10 tbsp (110g) of oil provides 990 kcals of energy. Hence, it is commonly known that fats such as oils and foods rich in fats should comprise a smaller proportion of total foods consumed. We discuss how much fat to eat in our Fab 5 Formula guide.
Benefits of Fats
It’s important to remember that fats are essential for health. Fats are an essential nutrient the body needs to function properly and therefore to maintain good health.
Fat supports the absorption of fat soluble vitamins (A, D, E and K). These vitamins need fat to be present in the body in order to function properly. Fat is also essential for many other functions from building and repairing the body’s cells and hormone production to being used as energy and keeping our skin plump and hydrated. Fats are essential (and they taste great!)
What Is Fat?
Fats can be a solid or a liquid at room temperature. Solids are classified as fats such as butter, margarine, lard and the fat you find in meats like beef or salami. Liquids are classified as oils such as olive oil, sunflower oil, vegetable oil and sesame oil. Both solid fats and liquid oils are fats.
Triglycerides are the most common types of fat we consume, but there are different types of triglycerides that are determined by the structure of the fatty acid. There are saturated fatty acids and unsaturated fatty acids.
You have probably heard that LDL cholesterol is “bad”, but why? Low-density lipoproteins (LDL) are a type of transportation parcel where cholesterol is carried away from the liver to parts of the body where it is needed.
When cholesterol is high it can be deposited on the walls of our arteries, known as atherosclerotic plaque. As time goes on and the plaque continues to build up, the artery becomes narrower and can restrict blood flow and therefore lead to a heart attack or stroke.
It is found that having high LDL cholesterol increases cardiovascular risk, due to its role where it has a higher potential of getting stuck. Therefore, reducing levels of LDL is the most reliable way of improving cardiovascular risk (1).
The link between saturated fat and cardiovascular risk is undeniable. A wide range of studies over the last seven decades have not only shown us that high saturated fat intake increases LDL cholesterol, but also that reducing consumption has the ability to lower both levels of LDL cholesterol and cardiovascular risk (2).
Should you avoid saturated fats? No. There’s no need to eliminate saturated fat from your diet, not only for your health but also for your soul! Most foods and oils (as you will see further below) contain a mixture of saturated and unsaturated fats, thus understanding the ratios can help you make better informed choices.
The UK guidelines recommend keeping saturated fat to no more than 30g a day for men or 20g a day for women. Instead of focussing on restriction, we advise focussing on the addition (or substitution) of unsaturated fats and keeping overall fats to no more than 35% of total energy intake (this is a guide, not a rule). Find out more in our Fab 5 Formula guide.
It’s not only the reduction of saturated fat that’s beneficial but what we end up replacing it with; the most benefit coming from unsaturated fats such as those found in olive oil. In fact, it is widely known that the Mediterranean diet is one of the most beneficial for cardiovascular health due to olive oil, or even better extra virgin olive oil.
Both monounsaturated and polyunsaturated fats are known as the good fats or healthy fats because they have heart and health benefiting properties. Research shows that they help to lower LDL cholesterol (3) and therefore reduce the risk of high blood pressure, heart disease and stroke (4) (5) (6).
Fats in Cooking Oils
When it comes to choosing which cooking oils and fats to use for cooking and baking on a regular basis, we advise choosing those with higher ratios of unsaturated fats than saturated fats.
As you can see in the graphs below, we have charted the breakdown of fats by types of oils and fats that are commonly used in the UK and most western countries (and some less common ones too). Although butter, ghee and margarine are not technically oils (they are solid at room temperature), we have included those for data comparison as they are commonly used for cooking.
Extra virgin olive oil and other cold pressed oils are unrefined and therefore have not undergone a chemical and heating process to extract the oils. The method of cold pressing oils retains much more of the nutrients. However, where it may not be practical or possible to purchase cold pressed oils, olive oil and other vegetable, nut or seed oils are great options.
The following graphs are ordered by the type of fat from highest to lowest.
Data sources: McCance and Widdowson’s The Composition of Foods integrated dataset (Co FID); USDA Food Composition Database, April 2018 (United States) via Nutrium.io
Isn’t Coconut Oil Healthy?
Besides coconut sounding healthy, some debate that the type of saturated fat in coconut oil helps raise HDL “good” cholesterol and that it consists largely of medium chain triglycerides (MCTs) which may be beneficial for health (7). Both these claims are false in terms of their intended outcome.
Yes, coconut oil does contain high amounts of MCTs, but what a lot of the media and product marketing overlook is the fact that coconut oil largely consists of the MCT lauric acid, which does not behave in the same way as the MCTs with health benefits. The MCT’s with health benefits make up only a very small proportion of coconut oil (8).
Although lauric acid does raise HDL “good” cholesterol, it also raises LDL “bad” cholesterol and the two do not mean they are offset. Research shows that raising HDL does not correlate with reduced cardiovascular risk (9) (10), but raising LDL absolutely does (11).
Coconut oil is 86.5% saturated fat and is shown to significantly increase LDL (12).
The best oil?
The absolute best oil is… it depends on the situation of course, but if we had to choose just one oil to recommend using on a daily or regular basis it would be extra virgin olive oil.
Olive oil is universally considered the healthiest source of fat (13), it improves heart health and is scientifically recognised by the European Food Safety Authority (EFSA) to have antioxidant properties (14).
But, don’t forget that variety is important! We love using different oils for different recipes depending on the taste and cooking method.
The Bottom Line
There’s absolutely no need to eliminate or fear saturated fats.
Fat is an essential nutrient - choose unsaturated fats more often as they have health benefiting properties.
Butter, ghee and coconut oil are rich in saturated fats and should be enjoyed sparingly.
Olive oil and other vegetable, nut and seed oils are rich in unsaturated fats and should be included as a source of healthy fats.