Just as proteins and carbohydrates are made of smaller components, so are fats. Most of the stored fat in our bodies (body fat) and fat found in food (dietary fat) exist in a form called triglycerides. These are made up of three individual fatty acids that are connected together by another molecule, glycerol.
Fat is an important foodstuff for many forms of life, and fats serve both structural and metabolic functions. They are necessary part of the diet of most heterotrophs (including humans).
Nutritionists often talk in terms of “good” fats, such as monounsaturated and polyunsaturated fats, and “bad” fats, like saturated and trans fats. Here’s a summary of the different categories of fats.
- A “good” fat
- Reduces overall cholesterol levels, and specifically LDL or “bad” cholesterol, while increasing levels of HDL or “good” cholesterol
- Found in nuts and seeds, avocados, olive oil and canola oil
- Another “good” fat
- Reduces overall cholesterol levels, and specifically LDL or “bad” cholesterol
- Found in fatty fish such as salmon, mackerel, trout and sardines, and also in corn, safflower, sunflower and soybean oils
- A “bad” fat
- Increases overall cholesterol levels, specifically LDL or “bad” cholesterol
- Found in animal-based foods such as meat, poultry and eggs, and also in butter, cream and other dairy products
- Also found in plant-based products such as coconut, so-called “tropical oils” like coconut oil, palm oil and palm kernel oil, and cocoa butter
- Another “bad” fat
- Increases levels of LDL or “bad” cholesterol and lowers levels of HDL or “good” cholesterol
- Found in hydrogenated fat products such as margarines and vegetable shortenings
- Used in packaged snack foods such as cookies, crackers and chips, and in fried foods from fast-food and other restaurants
The following table shows, in grams, how much saturated, monounsaturated, polyunsaturated are contained in 100 grams of various commonly used oils and fats. You may take attention this table when choosing foods for your health.