They sometimes get a bad rap, but carbohydrates, fats and proteins are the building blocks of the food we eat. A balanced intake of Macronutrients is crucial to our health.
How Macronutrients Work
- Carbohydrates
Carbs are the primary energy source for the body. They power the muscles, fuel red blood cells and charge up the central nervous system. Carbs range from simple carbohydrates or sugars – such as fructose (fruit sugar), sucrose (table sugar), lactose (milk sugar) and maltose (grain sugar) – to complex carbohydrates or polysaccharides such as starch, glycogen, and cellulose.
The liver converts all carbs into glucose, or blood sugar. Some glucose is used as energy, some is stored in the liver and muscles as glycogen, and some is converted into fat.
Carbohydrates that break down quickly into energy have the highest Glycaemic indexes (GI more than 70). Carbohydrates that break down slowly release glucose gradually into the bloodstream.
SOURCES: Bread, grains, rice, pasta, beans, fruit, and vegetables. Nutritionists recommend fruits and veggies and unprocessed products – i.e. whole foods and whole grains and with no added sugars or fat. Go lightly on breads, pastas and other high energy (high GI) carbs.
- Proteins
There are thousands of different proteins in the body. Our bodies need them for growth, fuel, maintenance, repair, and regulation. Proteins form body tissue, enzymes, hormones and antibodies. Proteins are in every one of our cells. Amino acids, the building blocks of protein, are provided by a balanced diet as well.
SOURCES: The best food sources of protein and essential amino acids are lean meat, fish, beans, dairy products (especially egg whites), legumes, beans and nuts.
- Fats
Yes, we need them. Fat molecules are made up of simpler units called fatty acids. Essential fatty acids store energy, insulate us and protect our vital organs. They provide fat-soluble vitamins, and help regulate growth, immune function, reproduction and basic metabolism.
Fatty acids can be either saturated (‘bad’ fat) or unsaturated (‘good’ fat). The more liquid the fat or oil is, the more unsaturated it is. Unsaturated fats decrease blood cholesterol just as saturated fats (from meat or dairy sources) increase cholesterol.
SOURCES: Oils, dairy (butter, margarine, cheese), meat, nuts, and snack or junk foods.
How many Macros?
The unit of energy is the kilojoule (kJ) or megajoule (1 MJ = 1,000 kJ)
4.18 kilojoules are equal to 1 kilocalorie.
Your macronutrient requirements can be measured as percentages of your EER, your daily Estimated Energy Requirements (kilojoules/calorie intake). The most recent Acceptable Macronutrient Distribution Range (AMDR) was published in September 2015.
The study figures out your energy requirements based on your age, height, weight and levels of activity. For example, for a woman aged between 31-50 who is 160 cm tall and weighs around 56.3 kilos, your basic requirements are 5.5 megajoules per day. Add to that a semi-active lifestyle (desk job), and your daily energy requirement goes up to around 8.7 megajoules. A more active woman, e.g. a mum and housewife, will burn upwards of 9.8 megajoules per day.
To determine your EER, and the EER for everyone in your family, visit www.nrv.gov.au/dietary-energy.
This article was first written for Goodlifehealthclubs.com.au