There is a lot of differing advice about whether eating more fat is OK or not. I have a lot of fat in my diet – but it comes mostly from plants and some dairy. The orthodoxy that unsaturated fat is better for you than saturated fat is being seriously challenged. So I reckon it helps to better understand fats – here is a summary on a New Scientist article I read recently.
What is a fat?
They are complex biomolecules that play many roles including energy storage and as components of cell membranes. A fat molecule is made up of 3 fatty acids bound to a molecule of glycerol. This unit is known as triglyceride there are dozens of different types of fatty acid all with different properties including whether they are saturated or unsaturated.
What does saturated/unsaturated mean?
A fatty acid molecule is made up of a long chain of carbon atoms with hydrogen atoms attached. An unsaturated fatty acid contains one or more double bonds in its carbon chain. A saturated fatty acid has no double bonds.
What about animal and vegetable fats?
Both plants and animals contain both types of fat but fats from animals tend to be saturated while those from vegetables are usually unsaturated. Eggs and dairy contain unsaturated fats while palm oil, coconut oil and the cocoa butter used in chocolate are higher in saturated fat than beef tripping or lard.
Is cholesterol a fat?
No, but it is a vital link between dietary fat and heart disease. Unlike saturated fat, cholesterol is almost exclusively found in animal products: meat, fish, seafood, milk and eggs. We now know that cutting the cholesterol in your diet doesn’t have as much direct effect on blood cholesterol levels but can help indirectly. This is because cutting down on cholesterol rich foods will usually reduce your saturated fat intake.
Are some fats more fattening than others?
No. A gram of unsaturated fat and a gram of saturated fat is about 9 calories. This compares to about 4 in a gram of sugar. So in terms of calories there are no good and bad fats.
How much is there in food?
28 grams of pure saturated fat is found in 600 grams of beef mince, 290 millilitres of sunflower oil, 133 grams of cheddar cheese, 72 grams of lard, 55 grams of butter.
Oil highest in saturated fat is actually a vegetable oil – coconut oil which is 87% saturated fat. 150 grams of milk chocolate contains 28 grams. Coconut oil contains more saturated fat than minced lamb: 30% vs 10%. Olive oil contains almost as much saturated fat as margarine: 14% vs 17%.
Beef dripping is just 50% saturated fat. Lard contains more unsaturated fat than saturated: 56% vs 39%. Eggs are only about 3% saturated fat.
And avocado contains as much saturated fat has 5 packets of crisps: around 3 grams. A large latte contains more saturated fat than a cream doughnut: 6.6 grams vs 6.2 grams. Nuts are richer in saturated fat than steak: 9% vs 3.5%
Categories: Health and Lifestyle