Fat: The Good, the Bad, and the Ugly
Beginning in the 1940’s, scientific studies saw a correlation between high-fat diets and high cholesterol. While correlation doesn’t always equal causation, low-fat diets were promoted for patients at high risk for heart disease. This diet began to catch on among all Americans in the 1960’s, and by the 1980’s the low-fat approach became an accepted truth promoted by scientists, media, the government, and the food industry.
However, according to pubmed.gov, there was no clear evidence that this diet prevented heart disease or promoted weight loss, even as many Americans subscribed to this idea. Ironically, as the low-fat ethos persisted, Americans became fatter and more unhealthier than ever. Obesity in the country rose to a level that was considered to be an epidemic.
Fat as a Macronutrient
All foods are made up of one, two, or all three macronutrients: protein, fat, and carbohydrates. The body needs fats to absorb vitamins, to provide energy, to build the walls of your cells, to insulate your body, and for essential fatty acids that can’t be made by the body – more on that later.
Within the scope of macronutrient fat there are four types:
- Saturated Fat
- Becomes solid at room temperature
- No double bond in chemical structure
- Found in animal-based foods like beef, poultry, full-fat dairy products, and eggs, and coconut oil
- According to heart.org, can raise the level of LDL cholesterol in your blood increasing risk of heart disease and stroke
- Monounsaturated Fat
- Chemical structure with one double bond
- Oils that contain monounsaturated fats are typically liquid at room temperature
- Examples are olive oil, canola oil, peanut oil, safflower and sesame oil, which have a combination of mono and polyunsaturated fats.
- Monounsaturated fats are believed to reduce bad cholesterol in the blood and are believed to be healthy in moderation.
- Polyunsaturated Fat
- Chemical structure with more than one double bond
- Liquid at room temperature and found mostly in fatty fish, plant-based oils, seeds, and nuts
- Trans Fat
- Some trans fats occur naturally in the gut of some animals and food made from them (milk and meat products) but this term mostly refers to artificial trans fats, created industrially by adding hydrogen to liquid vegetable oils to make them more solid (Partially Hydrogenated Oils)
- Eating trans fats is known to increase risk of developing heart disease, stroke, and developing type 2 diabetes.
Essential Fatty Acids
Polyunsaturated fats contain two essential fatty acids: omega-3, and omega-6. The numbers have to do with where the carbon-carbon double bond occurs in the chemical structure of the fatty acid, but for us non-chemists, we will remain concerned with their health benefits. Both omega-3 and omega-6 are essential for making eicosanoids, which are hormones important to the immune system, nervous system, and other hormones. Eicosanoids from the different fatty acids act differently; omega-3 promote heart health, support mental health, may help decrease fat in the liver, and fight inflammation. According to healthline.com, omega-6’s are mainly used for energy. The body is unable to make omega-3’s so it is crucial to get them through your diet.
Omega-3’s can be found in plant sources like flaxseed and flaxseed oil, walnuts, and chia seeds. Animal sources of omega-3’s care called docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), and can be found in fish. DHA and EPA are found in different kinds of fish, but since this is a category within a category within a category, let’s say that fish contain omega-3 fatty acids which are good for your health.
Omega-6 fatty acids can be found in seed oils like canola, soybean, and sunflower oil, and in nuts like walnuts, almonds, and Brazil nuts. Nuts contain mostly omega-6’s but also a smaller ration of omega-3’s. If you read our last article, however, it is advisable to go easy on the seed oils. Though they are a good source of mono and polyunsaturated fats, the heating and refining process may kill the antioxidants and polyphenols that remain in extra virgin olive oil, because there is no heating needed.
So What’s the Deal? Healthy or Not?
It is believed that the low-fat diet made Americans unhealthy because we lumped fat into one single word and banned it from our shelves – the truth is more complex. Yes, trans fats should be avoided. Most of the scientific and health community would also say to limit saturated fats found in animal products, although followers of the carnivore diet and keto diet would disagree, and we should enjoy quality healthy fats like mono and polyunsaturated fats found in oils and fish. When we banned all fat, we cut off all the benefits like improving heart health, supporting hormone function, support blood flow and inflammation, and ironically – maintaining a healthy weight. Unfortunately fat has become a loaded word over the years, but our health depends on battling that characterization. Fat is a good for us all, so let’s give fat a big fat welcome back!
2022 07 10