You probably grew up hearing that fat is bad for you. But now, that opinion has changed. The idea that fat is bad originated in the 1940’s when a few studies showed a correlation between high-fat diets and high-cholesterol levels. These results lead to the idea that low-fat diets are better. By the 1980’s, this idea was widely accepted across the United States.
However, the 1980’s was the decade that leads to what is commonly called the obesity epidemic.
So, what happened? Low-fat diets were supposed to improve health but the opposite happened.
Several aspects worked together, but as far as food consumption, the problem stemmed from the transition to low-fat. To replace fat, people turned to carbohydrates. Carbohydrates raise blood sugar levels and can lead to many serious health issues health issues.
The main problem, though, was the misconception of fats: different types of fat and how they affect the body. Today, there are many diets and studies to suggest high-fat diets are better than low-fat, such as ketogenic and low carb diets.
The studies in the 1940’s still hold some truth. Fat can lead to a rise in cholesterol levels, but only certain fats raise cholesterol. These are the fats to avoid.
Healthy Fat: Unsaturated Fat
Fat can be good for many reasons. In fact, healthy fat can improve cholesterol levels! Other benefits of healthy fat include:
- Major source of energy
- Helps the body absorb vitamins and minerals
- Builds cell lining or membranes
- Keeps the body warm
- Protects organs
- Aids in balancing hormones
Unsaturated fat is considered heart-friendly fat and the healthiest of the three types of fat. Unsaturated fat has two forms: monounsaturated and polyunsaturated which includes omega 3 and omega 6.
Unsaturated fat gets its name from its chemical structure. Unsaturated refers to the fact that unsaturated fatty acid (what makes up unsaturated fat) molecules are not completely surrounded by hydrogen atoms due to being double bonded.
Unsaturated fat contains one (monounsaturated) or more (polyunsaturated) double bonds. This means a single strand of unsaturated fatty acid might contain several carbon and hydrogen compounds linked with other carbon and hydrogen compounds.
The dashes signify a bond. This example image has two double bonds. In this case, the unsaturated fatty acid is technically polyunsaturated.
The double bonds mean the fatty acid can separate, so it does not clog arteries. Unsaturated fat also increases the creation of high-density lipoprotein (HDL) or “good” cholesterol. HDL can remove “bad” cholesterol from arteries and take it to the liver to be broken down.
Each of the types of unsaturated fat has various benefits. Monounsaturated protects the heart, supports weight loss, and supports insulin sensitivity. Polyunsaturated lower “bad” cholesterol. Omega 3 reduces triglycerides, slows plaque buildup in arteries, and lowers blood pressure. Omega 6 reduces the risk of diabetes, lowers blood pressure, and controls blood sugar.
Unsaturated fat is generally found in vegetables, nuts, and fish. The various types of unsaturated fat can be found in various foods.
- Olive oil
- Peanut oil
- Canola oil (though rendered unhealthy through heavy processing)
- Flaxseed oil
- Corn oil (though rendered unhealthy through heavy processing)
- Soybean oil (though rendered unhealthy through heavy processing)
- Sunflower oil
- Fatty fish
- Vegetable oil
- Leafy greens
- Vegetable oils
The recommended daily amount of healthy fat is between 44 to 77 grams per day based on a 2,000 calories diet
Additionally, most Americans consume too much omega six. The recommended ratio to consume omega 6 compared to omega 3 is 4:1. Most Americans consume 10:1 or more.
Unhealthy Fat: Saturated and Trans Fat
Saturated fats are completely opposite of unsaturated fat. Chemically, saturated fat is not double bonded. Instead, it is a single strand of carbon atoms surrounded by hydrogen atoms.
Since saturated fatty acid is in long strands with no gaps, the chains can pack tightly. These fatty acid strings increase the creation of “bad” cholesterol known as low-density lipoprotein (LDL). The increase in LDL and the saturated fat clog arteries.
Saturated fat increases cholesterol levels which, through correlation, means they can increase your risk of heart disease. It is best to avoid or limit foods with saturated fat, especially if you are on a typical high carb diet. Low carb, high fat diets have shown that saturated fats either have a neutral effect or actually improve cholesterol though, so it also depends on what the rest of your diet consists of.
- Butter and margarines
- Fatty meat such as beef and pork
- Skin of chicken
- Full-fat dairy products such as milk, cheese, and yogurt
- Palm oil
However, some of these saturated fatty foods are considered better than others. For example, dairy products are better than red meat. Also, grass-fed meat is better than non-grass-fed meat.
Trans fat is the worst kind of fat. It is found in small amounts naturally in animal foods such as meat and dairy. But most sources of trans fat are made through an industrial process called hydrogenation. The hydrogenation process is primarily used to turn healthy oils into solids to prevent them from going bad.
Additionally, trans fat helps foods last longer. It is found in many baked and fried foods, such as:
- Microwave popcorn
- Frozen pizza
This list pretty much covers every tasty treat, sadly. But it is trans fat that gives these foods it's great taste and texture.
Even though these foods taste wonderful, they should be avoided. Trans fat increases the risk of heart disease, stroke, and type II diabetes.
Trans fat foods often are sugary. This combination increases the danger of one of the bigger side effects of trans fat: decreased insulin sensitivity.
Insulin is key to helping cells absorb glucose. Decreased insulin sensitivity means your body generates more insulin when you consume glucose which increases initial glucose absorption. Cells receiving too much glucose will become inflamed and can lead to hypoglycemia.
Trans fat and sugar are not good combinations.
When focusing on consuming fat, replace as many, if not all, instances of fat consumption with unsaturated fat. Unsaturated fat will improve the health of your heart and will provide good energy for your body.
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