Written by Matt Dengler M.Ed, MS, RD, LDN
Macronutrients are the largest class of energy-providing nutrients the body requires which include carbohydrate, protein, and fat. These are the only nutrients that provide energy to the body. There are several micronutrients that help with providing energy, but only macronutrients provide calories for energy.
Example: If a product consists of 20g of carbohydrates, 5g of protein, and 0g of fat, the product would have 100 calories.
This macronutrient is needed the most out of all three, current USDA recommends adults require 45-65% of their daily caloric intake come from carbohydrates. Carbohydrates are easily broken down by the body for its main fuel source. When the body uses carbohydrates for fuel, the body can use the other macronutrients for other jobs like tissue growth and repair. For example, carbohydrates must be present in order for fats to be metabolized. Essential bodily functions like your brain, heart, muscles, and kidneys require carbohydrates to function properly and aid in the synthesis of amino acids.
These terms have to do with the chemical structure.
Simple carbohydrates have a much simpler chemical structure and are much easier to breakdown. Simple carbohydrates often have a sweeter taste, like fruit.
Complex carbohydrates are long complex chains of sugar molecules that take longer for the body to breakdown and often contain fiber like potatoes or brown rice. Complex carbohydrates are often thought to have a savory taste and will keep you fuller for longer due to the added fiber and nutrients that come with them.
Fiber is a form of indigestible carbohydrate that humans can’t breakdown, thus passing through the digestive track collecting waste. Diets lower in fiber can lead to indigestion problems like constipation, bloating, and hemorrhoids. Foods lower in fiber consist of refined carbohydrates such as white bread, white rice, white pasta, crackers, refined flour, etc. Conversely, diets high in fiber have shown to decrease obesity, heart disease, and cholesterol. Foods high in fiber consist of whole-grain bread, brown rice, fruit, vegetables, etc.
Carbohydrate Food Sources: Grains (i.e. rice, cereals, breads, oatmeal etc.), fruit, dairy, starchy vegetables (i.e. peas, corn, potatoes etc.), and beans. Some foods like nuts and seeds have smaller amounts of carbohydrates.
Currently, USDA recommends 10-35% of total calories be protein. Protein is necessary for more than just building muscle. Body cells are mostly made up of protein, making up for more than 50% of their weight. Protein can also define what an organism is and how it behaves. Since there are thousands of different proteins in the body, it is involved in many different processes like new tissue growth and repair. Protein also makes up most of our body’s enzymes and hormones that are used in digestion, protection, and immunity. Protein is used as a source of energy if carbohydrates are not available.
Protein food sources: meat, poultry, fish, dairy, cheese, soy, nuts, supplements. Other foods like some vegetables will have some smaller amounts.
Are all proteins created equal?
Short answer…No. Amino acids are the building blocks of protein, so when protein is consumed it is broken down into amino acids. There are hundreds of amino acids, but humans need 21 of them. Of the 21 amino acids, 9 of them are essential, meaning they are not created by the body and need to be consumed in the diet. Foods that are considered “complete proteins” are foods that contain all 9 essential amino acids. The foods that contain all essential amino acids are mostly found in animal sources. Plant foods also contain protein, but most don’t contain all the essential amino acids.
Vegetarian? Don’t fret, you can still get all of your essential amino acids without eating meat, but it will take more work. Combining plant-based proteins with other foods can help incorporate all of the essential amino acids in the diet. For example, combine grains with legumes (rice and beans, lentils and barley, bulgur with beans, or peanut butter with 100% whole wheat bread) to get your essential amino acids. Also, there are a select number of non-animal complete proteins as well: quinoa, soy, hemp seeds, and buckwheat.
Currently, the USDA recommends 20-30% of your total calories should be from fat. Fat is often avoided because people think it will make you fat and unhealthy. However, fat provides energy and is essential for vitamin A, D, E, K absorption. Fat is also imperative for the body’s insulation for body temperature regulation, protection for vital organs, cell membrane structure, lipoprotein structure, creation of hormones and bile acids. The main components of fat are fatty acids and play a pivotal role in brain development, reducing inflammation, and blood clotting. Your body can’t make some essential fatty acids so it must be consumed in the diet, such as linoleic (omega-6) and alpha-linolenic acid (omega-3). Omega-3 are converted to longer chains called eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). EPA and DHA have been shown to have a tremendous impact on improving and preventing cardiac events such as heart attack, heart disease, and heart failure most likely due to its ability to reduce/control inflammation.
What’s the difference between Omega-6 and Omega-3 fatty acids?
When targeting healthy fats, go for Omega-3 fats over Omega-6 fats. Omega-6 plays an important role in the manufacturing of signaling properties in the body, but the average American diet often contains a disproportionate amount of Omega-6s to Omega-3s. Studies have found the average American diet have shown an increase of Omega-6 to Omega-3 ratio to around 15:1. Higher Omega-6 polyunsaturated fats are often associated with inflammatory diseases like nonalcoholic fatty liver disease, cardiovascular disease, obesity, inflammatory bowel disease, rheumatoid arthritis, and Alzheimer’s disease. Conversely, Omega-3 fats have been found to be essential for growth, development, and help reduce inflammation. Increasing the amount of Omega-3 polyunsaturated fats to lower the ratio of Omega-6 to Omega-3 fats can help to reduce the incidence of these chronic inflammatory diseases.Fat food sources:
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