We often see or hear claims about a food product being “low in carbs”, “high in protein” or “fat free”. We thought it would be a good idea to get back to the basics and do a post on these 3 macronutrients. They are the source of practically all calories in food. They are called macro-nutrients because we need these in large quantities to function properly.
Foods generally contain different proportions of fats, protein, carbs and water. However, some foods are made up of only one macronutrient such as oil (pure fat) or sugar (pure carbohydrate). Let’s review each one of these macronutrients:
1. Carbohydrates (Carbs)
Contrary to many fad diets out there – Carbs are the main source of energy for our bodies. The most simple form of carbohydrate is glucose, the only substance our brains use for energy. Our kidneys, heart and nervous system also use glucose to function properly. Out of our total energy intake for the day, it is recommended to get around 45-65% of energy from carbs. So in a 2000 calorie diet this is 900 to 1,300 calories a day, or 225 – 325 grams (One gram of carbohydrate provides 4 calories). Our body can use the energy from carbs immediately, or store it for later use. Common sources of carbohydrates include breads, cereals, pasta, rice, potatoes, fruits and vegetables.
What are some good sources of carbs?
When choosing a carbohydrate it is important to select something that is high in fiber, low glycemic index and as least processed as possible. Examples include wholegrain bread, apples, sweet potatoes, brown rice and oats.
We only need about 10-35% of our diets to come from protein – most Americans get more than ample protein every day. Proteins are important for repair and growth of tissues, building muscle, enzymes, hormones, amino acids and our immune system. Protein isn’t used immediately for energy – it’s more of a backup for our body. One gram of protein, like carbs, also provides 4 calories.
Choose foods that have high quality protein: lean meats, fish, poultry, low fat cheese, milk, yoghurt, eggs, legumes, soy, nuts and seeds.
Fats should make up about 20-35% of our diet. Unfortunately, they’ve been getting a bad reputation for decades. Nonetheless, fats are essential in our diet. Fats are important for protecting our organs, maintaining cell membranes, promoting growth and development and absorbing essential vitamins. One gram of fat contains about 9 calories (more than double a gram of carb or protein, hence the vilification).
Which fats are good for you? Choose foods that contain unsaturated fats over saturated fats, such as oily fish, nuts and seeds, olive oil, avocado and canola oil instead of full cream milk, deep fried foods, cream, butter and animal fat.
So there you have it – the big three.
For those of you that are wondering where alcohol fits into the picture, it isn’t technically considered a “macronutrient” because our body doesn’t need it to function. However, if it is contained in foods or drink it adds quite a chunk of energy, almost the same amount as fat! One gram of alcohol has 7 calories!
There are many mixed messages out there regarding low carb, high protein diets. Most health professionals will not recommend these extreme diets as a way of obtaining enough nutrition for an active, healthy life. Following a balanced diet that contains carbs, protein and fat in the right proportions should give you all the nutrients you need!