Medically reviewed by Kathy W. Warwick, R.D., CDE — Written by Tim Newman — Updated on March 16, 2020 Fats are important macronutrients. There are several types of dietary fat, and some are much more healthful than others. Fat is essential for several bodily functions. It is an energy source, and it protects the skeleton and nerves. Fat also makes it possible for other nutrients to do their jobs. However, not all dietary fats are equally beneficial:
Meats, dairy products, snack foods, and baked goods contain saturated and trans fats. Some sources of unsaturated — healthful — fats include nuts, oils, seeds, and avocados. Below, we take an in-depth look at the different types of fats, including which are most healthful and which foods contain them.
Fats are classified in a range of ways, depending on their attributes:
Fats are an important part of the diet for humans and many other animals. The body stores fat for protection, warmth, and energy. Regardless of the type, all fats have the same number of calories — 9 calories per gram — compared with less energy-dense carbohydrates and proteins, at about 4 calories per gram. Different types of fat influence health in different ways, particularly blood and heart health. The next sections take a closer look at the effects of various fats on the body. Saturated fats are solid at room temperature and are sometimes called solid fats. The basic carbon structure of these fatty acids is “saturated” with hydrogen atoms. Saturated fat may increase health risks if a person consumes too much over a long period. A high intake of saturated fat may eventually raise levels of low-density lipoprotein (LDL) cholesterol in the body. This, in turn, increases the risk of cardiovascular disease and stroke. The American Heart Association (AHA) recommend that people eat no more than 13 grams of saturated fat per day. Some sources of saturated fat include:
Research indicates that it is not healthful to replace saturated fat in the diet with refined carbohydrates or sugar, which are also bad for health. Instead, a person should replace sources of saturated fat with more healthful foods, such as nuts, seeds, avocados, beans, whole grains, and vegetables. Unsaturated fats are liquid at room temperature, and they mostly derive from plant oils. Healthcare professionals consider these to be “good” fats. The two main types of unsaturated fat are: Monounsaturated fatsMonounsaturated fat molecules are not saturated with hydrogen atoms — each fat molecule has bonded with one hydrogen atom. Monounsaturated fats may lower LDL, or “bad,” cholesterol levels, and maintain healthful levels of “good” high-density lipoprotein (HDL) cholesterol. However, simply adding monounsaturated fat to the diet will not have this effect, unless a person also reduces their intake of saturated fat. Many health professionals report that a diet rich in monounsaturated fats may also reduce a person’s risk of heart disease. The Mediterranean diet, which research suggests may reduce the risk of chronic disease, contains plenty of monounsaturated fats. Sources of monounsaturated fats include:
Polyunsaturated fatsA number of spaces around each polyunsaturated fat molecule are not saturated with hydrogen atoms. Nutritionists report that polyunsaturated fats are good for health, especially those from fish and algae, known as omega-3 polyunsaturated fatty acids. The Office of Dietary Statistics say that omega-3 acids could help keep the heart healthy, reduce triglycerides in the blood, and improve brain, joint, and eye health. Omega-3 fatty acids may protect against heart disease by lowering blood cholesterol levels and, possibly, inflammation. That said, a large-scale Cochrane analysis found that omega-3 supplements had no significant benefits for heart health. Determining the effects with certainty will require further research. The other type of polyunsaturated fats are omega-6 fatty acids. These mostly occur in vegetable oils and processed foods. An excessive intake of omega-6, which is common in the standard American diet, may lead to increased inflammation. Sources of polyunsaturated fats include:
Trans fats are manufactured. They are the product of a process that adds hydrogen to liquid vegetable oils to make them more solid. Another name for trans fats is partially hydrogenated oils. Trans fats are not essential, and they have damaging health effects. Trans fats raise levels of LDL cholesterol and lower levels of HDL cholesterol. This increases the risk of heart disease, stroke, and type 2 diabetes. The World Health Organization (WHO) estimate that trans fats are linked with 500,000 cardiovascular deaths each year. Trans fats became popular when food companies found them easy to use and cheap to produce. They also have a long shelf life and can give food a nice taste. As trans fats can be used in commercial fryers many times over, they have become common in fast-food chains and other restaurants. However, the WHO have called on governments to eliminate trans fats from the global food supply. Most commercial food production companies have now eliminated trans fats from their products. Sources of trans fats can include:
If any ingredient list on food packaging includes “partially hydrogenated oils,” it means that the product contains trans fats. The AHA advise that consumption of trans fats should not exceed 5–6% of a person’s total caloric intake. However, consuming any amount of these fats increases health risks. According to the WHO, to avoid unhealthy weight gain:
Health professionals recommend replacing saturated and trans fats with monounsaturated and polyunsaturated fats. Overall, the diet should be nutritionally adequate and contain enough calories to maintain a healthy weight. Read our comparison guide of oils, including their nutritional and cooking values, here. Not all fats are equally beneficial. It is important to understand the differences between the types of fat, read labels carefully, and make healthful dietary choices. Last medically reviewed on March 16, 2020
For many years we’ve been told to avoid or significantly limit our fat intake, with all fats causing obesity, heart problems and more... But did you know there is such a thing as ‘healthy fats’? Healthy or 'good' fats are essential for human health. Studies show healthy fats can help reduce risk of disease, help extend your life, give your brain a boost and also give your skin a healthy glow. Your body requires fat intake from food as it is a major source of energy and also helps you absorb some vitamins and minerals. In Australia, the recommended guidelines say about 30% of daily calories should come from fat. It's also important to note that most foods rarely contain one type of fat and will commonly be a combination of a few. But which fats are considered good fats? And which kind should you avoid? Read on through our quick guide to find out! THE GOOD FATSThe good, healthy fats are Unsaturated Fats, which you’ll recognise on nutrition panels as monounsaturated fats and polyunsaturated fats (omega-3 and omega-6). These good fats come mainly from vegetables, nuts, seeds, and fish. They differ from saturated fats by having fewer hydrogen atoms bonded to their carbon chains. Healthy fats help the cholesterol balance in your blood by decreasing the bad (LDL) cholesterol and increasing the good (HDL) cholesterol. Monounsaturated Fat Sources of monounsaturated fat include: Polyunsaturated Fat You've likely heard of omega-3 and omega-6 fats: these are polyunsaturated fats. Polyunsaturated fatty acids are essential fatty acids – labelled as ‘essential’ because they are required for normal body functions however your body can't produce them itself. These fats must be obtained from food sources and the two omegas kept in balance. Although these fats are considered healthy and essential for a balanced diet, just like with all food groups, you still must be mindful of what and how much you’re eating.
THE IN-BETWEEN FATSThe in-between, or 'okay in moderation' fats are saturated fats. The word "saturated" here refers to the number of hydrogen atoms surrounding each carbon atom. The chain of carbon atoms holds as many hydrogen atoms as possible — it's saturated with hydrogens. Common sources of saturated fat include red meat, full cream milk, cheese, ghee and coconut oil. Is saturated fat bad for you? A diet rich in saturated fats can drive up total cholesterol and tip the balance towards more harmful LDL cholesterol. But that doesn’t mean there isn’t a place for it in a balanced diet. Foods that are naturally high in saturated fat can be healthy and nutritious, as long as you're eating quality unprocessed foods. Full-fat dairy, for example, can be an excellent source of protein, calcium, and phosphorous. Plus, its fat content helps your body absorb essential nutrients such as vitamins A, D, E, and K. For this reason, most nutrition experts recommend limiting saturated fat to under 10% of calories per day – but don’t be afraid to add it to your diet altogether!
THE BAD FATSThe worst type of dietary fat is the kind known as trans fat. Trans fat is known to increase our risk of heart disease by increasing the bad (LDL) cholesterol and lowering the good (HDL) cholesterol in our blood. Small amounts of trans fats naturally occur in dairy products, beef, veal, lamb and mutton, whereas industrially produced trans fats are commonly found in processed foods, junk food and fast food to help increase shelf life and save costs. Trans fats have no known health benefits and it is recommended that less than 1% of total energy should come from trans fat. Here at Honest to Goodness we are proud to have a range of products that contain NO NASTIES ADDED! This means that we don't supply any food or ingredients with hydrogenated oils, which are also known as trans fats. References Barberger-Gateau, P. (2002). Fish, meat, and risk of dementia: cohort study. BMJ, 325(7370), 932-933. doi: 10.1136/bmj.325.7370.932 |