The more you understand basic nutrition, the better informed you will be about making healthy choices. To function properly, our body requires macronutrients, nutrients needed in larger amounts, and micronutrients, nutrients needed in smaller amounts. In this blog, we will cover the macronutrients that our body needs. All macronutrients provide our body with energy in the form of calories (denoted as kcal). The amount of calories per gram of macronutrient is shown below so you have a better understanding of how much each macronutrient contributes to our caloric intake.
Carbohydrates
Carbohydrates are sugar molecules that our body breaks down into glucose. They provide our body with 4 kcal/g of energy. All organs, our brain especially, require glucose to function. However, the types of carbohydrates that we consume are very important. Complex carbohydrates, found in whole grains, legumes and fibre-rich vegetables, release glucose slowly into our blood stream and give us sustained energy. In contrast, simple carbohydrates, found in white bread, white rice, white pasta, and sugary snacks, cause our blood glucose levels to spike which gives a quick energy boost followed by a quick drop in energy levels. These spikes can lead to health problems including diabetes, high cholesterol, heart disease and weight gain. Carbohydrate-rich foods ranked as having a low glycemic index are healthier because blood sugar levels to rise slower and lower.
Protein
Proteins provides 4 kcal/g of energy as well. They contain amino acids that mainly serve as our body’s building blocks and are required for proper functioning of nervous, immune, reproductive and digestive systems. Our body needs 20 amino acids, and nine of these are called essential because they can only be obtained through diet. Animal sources of protein contain all of the essential amino acids whereas vegetable/legume sources can contain varying amounts of essential amino acids. This is why it is very important for those on a vegetarian diet to eat a wide range of foods to ensure that all amino acid requirements are met. For example, rice and beans complement each other perfectly by providing all nine essential amnio acids when consumed together and are thus considered a complete protein source.
Fat
Fat provides more than twice the amount of calories as carbohydrates or protein (9 kcal/g). Fat is essential to our diets, but there are good fats and bad fats. Two types of good fats, shown to be protective for heart disease, are monounsaturated (omega-9) and polyunsaturated fats (omega-6 and omega-3). Omega-3 fats are considered to be healthier than omega-6 and are found in high levels in fatty fish like salmon. Good plant sources include flax seeds, walnuts, canola oil, and soybean oil. Unsaturated fats are liquid at room temperature.
Saturated fat is considered to be not as healthy as the unsaturated fats, and is the type of fat mostly found in animal foods (meat and dairy) or foods containing animal by-products. Some plant foods (coconut, coconut oil, palm oil, and palm kernel oil) also contain high levels of saturated fat. Saturated fats are solid at room temperature. Recent studies indicate that saturated fat is not as bad as was previously considered, but replacing it with unsaturated fat in your diet can reduce inflammation, heart disease risk, cancer risk, and potentially cognitive decline.
The worst type of fat for your body is trans fat. It is made by hydrogenating, or solidifying, liquid vegetable oil (unsaturated fat)). Margarine and shortening are examples of this. Partially hydrogenated fat is used a lot in restaurants and the food industry because it makes the oil more stable and less likely to go rancid. Many baked goods and processed snack foods contain partially hydrogenated oils. A type of trans fat found naturally in beef and dairy fat in small amounts (conjugated linoleic acids) appears to have different health effects compared to manufactured trans fat and may have some health benefits. However, all studies investigating conjugated linoleic acids are done in supplement form.
The amount of each macronutrient required in a healthy diet can vary depending on your individual needs. The acceptable ranges for each macronutrient are:
- 45-65% of calories from carbohydrates
- 20-35% of calories from fat
- 10-35% of calories from protein
Food tracking apps can help you calculate what your typical macronutrient intake is. Consuming nutrient-dense, low glycemic index foods that contain fibre, lean protein, healthy fats as well as micronutrients such as vitamins, minerals and phytochemicals (found in plants) is a step in the right direction.
