This is the first of 4 installments to what runs our bodies: 1) fat, 2) carbohydrates, 3) proteins, and 4) water. For this first post under Nutrition I thought the topic of Fat would be an attention getter. We all talk, think, dream about and eat fat!! Most women think they have too much, or that what they do have is not in the right area. Men just like to eat fat flavored food! But seriously, what is fat? Does it do anything besides annoy us and cost us $$$?
The surprising answer is yes. First let’s get some basics down.
Calories – we equate fat with calories, and that is correct. So what exactly is a calorie? A calorie is a unit of measure. It measures the amount of energy, or heat, it takes to raise the temperature of one gram of water one degree C. (or 1.8 degrees F.). Food nutrition labels give the number of calories in a specific serving size. (These are actually kilocalorie.) Fat has 9 calories per gram, carbohydrates & protein contain 4 calories per gram. So one gram of fat = 9 calories and one gram of carbohydrates or protein = 4 calories. Our bodies require a certain amount of calories for it to function properly. But there’s more to it than that. Where should these calories come from? They come from three sources: fat, carbs, and proteins. This post is going to be all about FAT!
What is fat? It is a combination of 3 fatty acid molecules and 1 molecule of glycerol. The fat cells in the body do not multiply greater in number, just greater in size. So what does fat do in the body anyway? To answer this we must first know that there are two types of fat tissue – white (or “yellow”) & brown.
White Fat – Also known as storage fat, is what we refer to when we say “I’m so fat”. It has two main functions – a) storage of energy and b)produces hormones. When we go without food for 4-6 hours this white fat is broken down and used as fuel for energy, hence the name “storage fat”. This fat is needed for the production of hormones. Some other attributes of white fat are:
- helps satiate us when we eat it in its natural form
- insulates us from cold and heat
- serves as protection to bones and organs from shock
- prevents fatty acid deficiency
- insulates and surrounds nerve fibers
- is a component in cell membranes
- helps body metabolize fat soluble vitamins as vitamins A, S, E, and K
White fat located under the skin is called sub-cutaneous fat, this is what is measured to find body fat percentage. Visceral fat is fat found in the abdominal cavity around the internal organs. Too much visceral fat may engender health issues.
Brown fat – This fat is less abundant. Its main function is to generate heat, and it has a higher number of mitochondria which contain a high amount of iron. This gives it its dark reddish-brown color and why it is called brown fat. Babies, children, and animals that hibernate have higher levels of brown fat. When brown fat is stimulated it will actually burn white fat. Brown fat is found in bone marrow, organs, central nervous system, and muscles.
So that is a partial rundown of body fat. Let’s move on to dietary fat. Here is where we get our supply of fat, and it does matter what kind we choose to take in. There are 4 types of dietary fat.
Saturated fat is a fat that has all the “places” on the carbon chain filled with hydrogen and has no double or triple bonds. It is solid at room temperature. Some examples are animal fat, cream butter, and cheese. This is the fat the American Heart Association warns us about.
Trans-fats are fats not found in nature, but are man-made. This type of fat is made from a hydrogenation process of an unsaturated fat making it stable and solid at room temperature. Some examples are vegetable shortening, margarine, and soft tub spread. Body cells do not recognize this substance and it may be quite harmful. They are used to make commercial baked goods.
Unsaturated fat has two types, monounsaturated and polyunsaturated.
Monounsaturated fats have one double bond in the carbon chain. It is liquid at room temperature.
Polyunsaturated fats have more that one double bond in its carbon chain. This fat is known as the “healthy fat”.
Monounsaturated Fat Sources
- olive oil
- sunflower oil
- peanut oil
- sesame oil
- nuts (peanuts, macadamia, hazelnut, pecans, cashews)
- peanut oil
Polyunsaturated Fat Sources
- soybean oil
- corn oil
- safflower oil
- sunflower, pumpkin, sesame seeds
- flax seeds
- fatty fish – salmon, tuna, trout, herring, mackerel
What we learned – we need fat in the diet! Wierd to say that or to think it, but it’s true. However make sure it is the right form of fat, naturally occurring in nutritious food.