What are Dietary fats?
Dietary fats are classified as ‘lipids’. Lipids are a category of organic substances that are insoluble in water, but soluble in certain solvents such as alcohol. There are 3 major types of lipids – Triglycerides, Cholesterol and Phospholipids.
Triglycerides
Also known as true fats or neutral fat. Triglycerides are basically fats that are eaten and stored in the blood to use as energy. They are necessary for the human body but harmful when taken in excess.
Cholesterol
Known as sterols. Found only in animal products. Not found in fruits, vegetables, nuts, grains, or other non-animal foods. Cholesterol may be added to some foods, such as bread, (e.g. from eggs) Cholesterol is not an essential nutrient for humans. It can be manufactured in the liver from fatty acids or the breakdown products from Carbohydrates and Protein (glucose and amino acids).
Hence, contrary to popular belief, certain Cholesterol is needed in our body, however, our body can produce the essential Cholesterol and there is no need to intake it from food.
Cholesterol also consist of 2 different types: HDL and LDL
HDL stands for high-density lipoprotein. HDL takes cholesterol from body tissue back to the liver. Known as "Good" cholesterol. Reduces risk when taken in a high amount
LDL stands for Low-Density Lipoprotein. LDL takes cholesterol from the liver to the rest of the body. Known as “Bad” cholesterol. Increases risk when taken in high amount
Phospholipids
Another type of lipid that is similar to triglycerides. Common phospholipids are lecithin. Phospholipids are not essential nutrients. It can be made from triglycerides. Examples of foods that contain lecithin are egg yolks, milk and peanuts.
Now, we dive into the type of lipids that are more applicable to the general population; fats, and the types we can find in food.
Good Fats (Monounsaturated and Polyunsaturated)
Lowers HDL and Lowers LDL (Polyunsaturated)
Lowers LDL and raises HDL (Monounsaturated)
Lowers total cholesterol
Lower risk of heart disease & stroke
Provide essential fats that the body needs but can’t produce
Sources: Plant-based liquid Oils, nuts, seeds and fatty
Examples (Monounsaturated): Oils (canola, olive, Peanut, sunflower)
Examples (Polyunsaturated): Fatty Fish (Salmon, Mackerel, Herring, Trout)
Bad Fats (Saturated)
Raises LDL
Lower HDL
Raises total cholesterol
Increase the risk of heart attack & stroke
Most saturated fats came from animal sources, including meat and dairy, and from tropical oils
Really bad fats (Hydrogenated oils & Trans fats)
Raise LDL
Lower HDL
Raises total cholesterol
Levels increase the risk of heart disease and stroke
Increase risk of type 2 diabetes
Processed foods made with partially hydrogenated oils
Fat as compared to other Macronutrients
As compared to the other Macronutrients, Carbohydrates and Proteins, 1g of fats = to 9 kcal of calories. Carbohydrates provide energy more quickly as compared to fats, hence fats are great fuels for endurance but not as much for sprints.
How much fat and cholesterol are needed in our diet
In our diet, it should consist of around 20-30% of fats. So, if you are on a 2000 Calories diet, you should maintain around 400kcal to 600kcal or 44g to 66g of fats. For cholesterol, keep it to around 100mg per 1000 calories. As mentioned above, there are different types of fats. As much as possible, consume the good fats and limit yourself on the unhealthy fats, and stay away from trans fats 😡
