Fat generally gets a bad rap, but healthy fats are crucial for proper body function. In addition to carbohydrates and proteins, fats are macronutrients - nutrients that our bodies need in large amounts. Understanding dietary fats can make it easier to make healthy food choices.
Our food intake should consist of 20-35% fat. What does this look like?
1,500 calories: about 33-58 grams of fat per day
2,000 calories: about 44-78 grams of fat per day
2,500 calories: about 56-97 grams of fat per day
At least 90% of fat intake should be from healthy fats. This should be divided throughout the day so as to not overload our system.
Benefits of Healthy Fats:
Energy: Fats are high in energy and are more energy-dense than carbohydrates and proteins. One gram of fat provides 9 calories of energy while each gram of carbohydrate and protein provides only 4 calories of energy.
Nutrient Absorption: Vitamins can be classified as water-soluble or fat soluble. Fat soluble vitamins - including vitamins A, D, E and K - need fat in order to be used by the body. These nutrients are essential for vision, bones health, and immune function.
Protection: Fat acts as a cushion to protect our organs.
Insulation: Fat acts as an insulator and helps keep our bodies warm.
Hormone Production: Fat actually produces various hormones. Leptin (important in maintaining a healthy body weight) and vitamin D (crucial for proper cell and organ function) are produced by fat.
Optimal Cell Function: Fat cells support cell function and play a critical role in regulating metabolism.
Stable Blood Sugar: Fat has little direct effect on blood glucose levels and actually helps delay spikes in blood sugar.
Satiety: Although many factors affect digestion, our bodies generally digest carbohydrates in 2 hours, proteins in 2-4 hours, and fats in 3-5 hours. This means that foods containing fat leave us with a sensation of feeling full for a longer period of time.
Types of Fats:
Healthy Fats
Monounsaturated Fats: These fats help lower cholesterol and the risk of heart disease. Examples include olives, olive oil, avocados, and avocado oil.
Polyunsaturated Fats: In addition to helping lower cholesterol and the risk of heart disease, polyunsaturated fats also help lower blood pressure. Examples include nuts, seeds, flax, and fish.
Omega 3 Fatty Acids: These fats are linked to heart health and brain health. They are associated with lower levels of inflammation, helping decrease risk of chronic disease. It is recommended to consume omega 3 fatty acids at least 2x/week. Examples include walnuts, chia seeds, hemp seeds, flaxseed, tofu, soy, and fatty fish (like salmon, tuna, sardines, and herring). Some eggs are also a good source of omega 3 fatty acids - the food fed to the chickens makes a difference!
Unhealthy Fats
Saturated Fats: Saturated fats are associated with increased health problems, particularly high cholesterol and heart disease. These fats should be consumed in moderation and should be less than 10% of fat intake. Examples include palm oil, coconut oil, butter, cheese, full fat dairy products, high fat beef, pork, and processed foods (like cookies and donuts).
Trans Fats: These fats are the least healthy fats with no known health benefits. They are associated with increased risk of heart disease, stroke, and type II diabetes. Due to their dangers, trans fats have been largely removed from our food system. Prior to being banned by the FDA, trans fats were added to foods to lengthen their shelf life. Partially hydrogenated oils contain trans fat.
Healthy dietary fats give us energy to perform daily tasks, help support our body function, and help protect us from chronic disease. As with everything, moderation is key and a little bit goes a long way.
References:
Marchini, Peggy. "Understanding Macronutrients: Fats." Northwestern Medicine Leishman Center for Culinary Health, April 2024.
"Enhancing PT Patient Outcomes Through the Introduction of Clinical Nutrition." APTA, April 2024.
Morris, Tracy. "How Counting Macros Can Help You Reach Your Health Goals." Fitbit, April 2017. https://blog.fitbit.com/counting-macros-can-help-reach-health-goals/