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What is Dietary Fat, and Why Do We Need it?

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What is Dietary Fat, and Why Do We Need it?

Consuming fats in your diet is necessary for overall health. For years fats were critiqued and banished from people's diets. Low-fat diets were the fad from 1960 to 2000 due to limited scientific evidence. In recent decades, the tides have shifted due to research and the fact that fats are an essential macronutrient. Fats provide a source of energy, help your body absorb nutrients, regulate cholesterol, and contribute to brain and neurological development. Although fasts are necessary, not all fats are created equal. The type of fat and how much you consume are important to consider. Creating a well-balanced dietary intake of healthy fats over bad fats is one way to contribute to more beneficial outcomes.


What is Dietary Fat, and Why Do We Need it?

Dietary Fats are categorized into Unsaturated, Saturated, or Trans Fats. Unsaturated fats provide the most beneficial nutrient content for health and can help decrease your risk for certain diseases. Saturated fats can have beneficial and harmful effects, depending on the types you consume. A general consensus is that saturated fats should be consumed in moderation, whereas trans fats ("bad" fats) should be avoided at all costs.

What are Good Fats?

When it comes to overall health, dietary fats are essential. You'll want to check the types of fats you are consuming, as research has revealed that some fats are better for us than others. A rule of thumb is to primarily consume unsaturated fats, limit saturated fats and avoid artificial trans fats. Good fats that you will want to focus on are monounsaturated and polyunsaturated fats, from which you'll want the majority of your fat content to come from.

The 2020-2025 Dietary Guidelines for Americans recommends starting at age 2, Americans should consume no more than 10% of their fats from saturated fat. The remaining 20% of the daily caloric recommendation of fat consumption should be from unsaturated fats. Eating olive oil, avocados, almonds, pecans, walnuts, flaxseed, pumpkin, and sesame seed will increase your unsaturated fat intake. Omega-3s are one of the best sources of polyunsaturated fats and can help you achieve healthy fat consumption.

Unsaturated Fat

Unsaturated fat is typically liquid at room temperature and can be divided into monounsaturated fat or polyunsaturated fats. Consuming more unsaturated fat over saturated fat has been shown to improve cholesterol levels and reduce your risk of cardiovascular events and stroke. Types of unsaturated fats include

Monounsaturated fats

  • Canola
  • Olive
  • Avocado
  • Peanut
  • Almonds, hazelnuts, and pecans
  • Sesame and pumpkin seed
  • Safflower

Polyunsaturated Fats (PUFA)

  • Canola and soybean
  • Sunflower
  • Corn
  • Flaxseed
  • Walnuts
  • Fish

Fatty Acids

Fatty acids are a subcategory of polyunsaturated fats. This is further divided into Omega-3 and Omega-6 fats. Both Omega-3 & Omega-6s are essential fatty acids, meaning your body does not make them, and you must get them from your diet.

Omega-3 fatty acids are the all-star when it comes to polyunsaturated fats, as they have many health benefits. Yet many people under consume omega-3's.

Most people do not have an issue getting enough Omega-6 fatty acids, as it is commonly found in processed foods, packaged foods, vegetable oils, seeds, and nuts.

Foods High in Omega-3's

  • fish-salmon, mackerel, trout, tuna, sea bass, and sardines.
  • Oysters
  • Scallops
  • Walnuts
  • Chia seeds
  • Flaxseed

Foods High in Omega-6's

  • Canola oil
  • Sunflower seed
  • Walnuts
  • Safflower oil
  • Egg yolk
  • Tofu

What are Bad Fats?

Saturated and trans fats are known as the "bad" fats due to the potential impact they can have on your health. While trans fats should be avoided because they are an undeniable risk factor for heart disease, stroke, type 2 diabetes, and high cholesterol, saturated fats are a more complex picture.

Saturated Fats

Saturated fats are solid at room temperature and are found in animal-based foods, milk-based products, and tropical fats. The American Heart Association recommends limiting saturated fats as they have been shown to raise "bad" cholesterol and put patients at higher risk for heart disease. Recent research shows that overly processed foods like sausages and deli cheese have higher saturated fat levels than pastured raised grass-fed beef and dairy. They also react differently in the body. Processed and conventional farmed saturated fats have been shown to cause inflammation. At the same time, pasture-raised grass-fed meat and dairy are higher in Omega-3s vs. saturated fat and have been shown to have the ability to lower inflammation. Science is continuing to discover more on this topic, but it's still recommended to limit saturated fats and focus more on unsaturated fats to meet your macronutrient needs. Types of saturated fats are:

  • Coconut oil
  • Milk fats
  • Butter
  • Tallow
  • Beef
  • Pork
  • Cheese
  • Yogurt
  • High-fat meat
  • Lard

Trans Fats

Trans fats come in two forms- naturally occurring and artificial trans fat in the form of hydrogenated oils. Artificial trans fats are produced by adding hydrogen to liquid vegetable oils and adding them to food items. As of June 18th, 2019, the U.S. Food and Drug Administration has banned manufacturing partially hydrogenated oils due to their harmful effects on health. Here are examples of both:

Naturally occurring trans fats

  • Milk
  • Butter
  • Beef
  • Pork
  • Lamb

Artificial trans fats are made of Partially Hydrogenated Oils (PHO), was present in

  • Vegetable shortening
  • Margarine
  • Previously it was commonly found in microwave popcorn, some frozen foods, commercial baked goods, fried food, and packaged snack foods.  

Research Behind The Health Benefits of Good Fats

There are many health benefits to eating unsaturated "good" fats. Here are some of the ways unsaturated fats can enhance your health.

Optimize Cholesterol

Unsaturated fats have a positive impact when it comes to LDL and HDL markers of cholesterol. Monounsaturated fats have been shown to lower LDL cholesterol, while Polyunsaturated fat-DHA has been shown to lower triglycerides and increase HDL. Both have great potential in stabilizing cholesterol in comparison to saturated fats.

Lower Blood Pressure

Omega-3 fatty acids may be the best form of polyunsaturated fatty acids for heart health and beyond. One review of research found that amongst 71 clinical trials between 1987-2020, the consumption of 3g of DHA and EPA omega-3 fatty acids resulted in an average reduction of 4.5 mm Hg in those with hypertension.

Support Brain Health

There are many nutrients necessary for brain development and function. Unsaturated fats in the form of omega-3s have been shown to be important in fetal brain and nervous system development. Throughout life, healthy fats contribute to overall brain health while also providing nutrients that have promising results in treating depression, preventing dementia, or managing cases of epilepsy.

Reduce Premature Mortality

Unsaturated fats in one's diet were looked at from the standpoint of mortality risk. In a prospective observational study, researchers found that those who had consumed more unsaturated fats compared to saturated fats had a reduced risk of mortality by 7%.

Decrease Inflammation

Inflammation is a normal response to bodily processes. The disease can then arise when inflammation becomes a predominant and chronic response. Supplementation of Omega-3 PUFA has been shown to prevent inflammation in conditions with an inflammatory component.

Aides in Nutrient Absorption

Some nutrients require a "helper" to get them into the cells. Fats are foundational for getting fat-soluble vitamins A, D, E, and K into your cells for utilization. This study reveals that taking vitamin D-3 with fats significantly enhances the absorption of the vitamin compared to taking vitamin D3 supplementation with fat-free meals.

Research Behind The Health Risk of Bad Fats

While the type of saturated fats is essential to consider, there are detrimental health effects from consuming excess processed saturated fats and trans fats.

Increased Risk of Heart-Related Issues

Studies have shown that diets high in SFAs are associated with an increased risk of coronary heart disease. There is conflicting information on this topic, and more studies are showing that it's the type of saturated fat consumed that may increase heart disease risk. Limiting the amounts of saturated fats in the diet and focusing more on unsaturated fats to meet your macronutrient needs are still recommended by the American Heart Association.  

Increase Cholesterol Levels

Trans fats are the worst type of fats to consume, primarily for their effect on cholesterol. Trans fats create an imbalance by increasing your "bad" LDL cholesterol while decreasing your "good" HDL cholesterol. A diet laden with trans fats increases the risk of heart disease, one of the leading causes of death in adults. Trans fats are so unhealthy that the FDA has prohibited food manufacturers from adding the major source of artificial trans fats to foods and beverages. Several countries and cities in the United States have also limited or banned the use of trans fats.

Promotes Inflammation

Activation of inflammatory processes and endothelial dysfunction are two of the ways in which trans fats promote inflammation. Evidence suggests that trans fatty acids create a pro-inflammatory environment that can lead to atherosclerosis, acute coronary syndromes, sudden death, dyslipidemia, heart failure, and insulin resistance.

Try These Tips To Reduce Unhealthy Fat In Your Diet

Staying within the dietary guideline of limiting saturated fat to less than 10% of total fat intake is an optimal way of controlling fat in your diet. To fill in the gap in fat consumption, you can replace saturated fats with foods rich in unsaturated fat. Try implementing these tips to reduce unhealthy fat in your diet:

  • Use an omega-3-rich oil for cooking. For example, olive, avocado, and coconut oil are all great options.
  • Eat fish rich in omega-3 fatty acids, such as salmon, at least twice a week
  • Opt for grass-fed meat, lean poultry, and wild-caught fish
  • Limit processed foods, which often contain saturated fat and potentially trans fat. Although synthetic partially hydrogenated oils are now prohibited from being added to American food, they can still contain natural forms of trans fats.
  • If it has a label, read it and look for hidden trans and saturated fats.
  • Reach for fresh fruits and vegetables in place of packaged food and snack items.



The foods you consume can profoundly impact your health and well-being. Making a conscious decision about your food changes the trajectory for at-risk conditions such as heart disease and premature mortality. While fats are necessary for your health, avoiding trans fats, consuming primarily unsaturated fats, and being selective about your saturated fat intake is important. If you are at risk for cardiovascular disease, have elevated cholesterol, or suffer from other conditions, unhealthy fat intake may exacerbate it. It is always best to consult your functional medicine practitioner on the best nutrition plan for you.

The information provided is not intended to be a substitute for professional medical advice. Always consult with your doctor or other qualified healthcare provider before taking any dietary supplement or making any changes to your diet or exercise routine.
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