Lipids, or fats, play essential roles in maintaining your overall health. They're so important that the Institute of Medicine recommends adults consume 20 to 35 percent of their calories per day from fat. For a 2,000-calorie diet that means consuming between 44 and 78 grams of fat per day. Meeting, but not exceeding, these guidelines will ensure you're getting enough lipids to help keep your body functioning at its best.
Roles in Your Body
While few people desire to have extra body fat, your body needs some lipids to maintain your health and body systems. Lipid stores in your body function as an energy reserve to fuel your essential body functions, such your heart beating and breathing, when you go a long period of time without eating. Lipids also play a role in the formation of your cell membranes. Deposits of fat in your body help support and protect vital organs including your heart, kidneys, liver and spleen. Lipids also provide insulation to prevent major temperature fluctuations as well.
Lipids provide a more dense form of energy, or calories, than carbohydrates or protein. A gram of fat provides 9 calories, whereas a gram of carbohydrate or protein only provides 4 calories. For this reason, fats are able to help you feel full on a small volume food and can be useful when food is scarce. If you're underweight or have a very poor appetite, fats can also be useful to provide you with the energy you need. However, if you consume more lipids than your body can use as energy in a day, the remainder is stored in fat cells in your body for later use.
Absorption of Vitamins
In addition to its other roles, fat aids in the absorption and storage of certain essential vitamins. The fat-soluble vitamins A, D, E and K all rely on lipids for absorption, transport and storage in your body. They can't be absorbed or excreted in fluid the same way the water-soluble vitamins can. If you consume more of the fat-soluble vitamins than your body needs at one time, they are stored with lipids in your liver and tissues for later use. Getting enough of the fat-soluble vitamins helps maintain your vision, reproductive health, immune system, bone density, heart health and blood clotting, according to the Colorado State University Extension website.
Essential Fatty Acids
Certain types of lipids are considered essential fatty acids because your body is unable to make them and they must come from your diet. Omega-3 fatty acids are one type of essential lipid found in fatty fish, such as tuna, salmon and halibut, and certain nuts. These lipids are essential to maintaining proper brain function and may reduce inflammation in your body. Meeting your needs for essential fatty acids may also help reduce your risk of developing heart disease, cancer and arthritis, notes the University of Maryland Medical Center website.
- Institute of Medicine: Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids
- Virtual Chembook, Elmhurst College: Overview of Lipid Function
- Colorado State University Extension: Fat-Soluble Vitamins: A, D, E, and K
- University of Maryland Medical Center: Omega-3 Fatty Acids