Back at the end of February I spoke about how to work out your calories, using your BMR (Click here to read again), but all food isn’t equal, so simply focusing on your calories is just the start. The basic building blocks that our food consists of are Carbohydrates (Carbs), Protein and Fats. These are often referred to as Macro-nutrients, or simply Macros.
Carbohydrates are split into two main groups, simple and complex. Simple Carbohydrates are found in sugar, products containing refined flour, sweets, sweetened soft drinks and fruit juices, and should be avoided where possible. They can lead to spikes in blood sugar, which over time can lead to insulin resistance. Complex carbohydrates are found in fruit, vegetables, legumes, cereals and grains, whole grain products and brown rice. They don’t have the same affect on blood sugar levels, and in addition keep you feeling fuller for longer than simple carbohydrates. They also have many other nutrients in them (called micro-nutrients) as well as fibre, can help gut health and may help manage cholesterol levels. Carbohydrates are the body’s preferred source of energy in terms of mental and physical activity.
Proteins are made up of smaller building blocks, called amino acids, and in total there are 20 different amino acids in the body. What is important to know is that amino acids themselves are split into 2 categories; essential and non-essential, and that the human body can’t produce sufficient essential amino acids, so they have to come from what you eat.
Protein sources are sometimes called complete or incomplete proteins, which indicates whether they have an adequate proportion of each of the nine essential amino acids. Complete protein sources include red meat, poultry, fish, eggs, dairy, soybeans and quinoa. However, by eating a variety of foods during the day you should have enough of each of the amino acids, whether you are an omnivore, vegetarian or vegan.
Proteins are one of the building blocks of body tissue, skin, hair and muscle fibre, and also function as hormones, enzymes and antibodies. Protein isn’t a direct source of energy but can be used indirectly. As well as the complete protein sources already mentioned, other foods which are high in protein (but don’t contain all nine essential amino acids) are other grains and nuts.
The amount of protein you should consume on a daily basis depends on your body composition and what you are trying to achieve. The minimum you should be looking at consuming is one gram of protein per kilo of your own weight (note that one gram of protein is not one gram of a protein source, for example, a skinless, cooked chicken breast (172 grams) contains 54 grams of protein). This amount may go as high as 1.75 or 2 grams of protein per kilo of your own weight for fat loss, for example.
Fats come either in solid or liquid form, and are divided into Saturated Fats (such as animal fats, dairy, butter, and coconut butter), Mono- and Poly- Unsaturated Fats (including olive oil, cold water fish, avocado, and nuts), and Trans Fats (such as baked goods, fried foods, and some margarines). Omega-3 and omega-6 fatty acids come under poly-unsaturated fats.
Unsaturated Fats are used to regulate metabolism, improve blood flow, and are important for cell health. Fats are also used to transport the fat-soluble vitamins A, D, E and K. Animal fats provide cholesterol, which is essential for some processes in the body, but there needs to be a balance to ensure that cholesterol does not go too high, due to the increased risk of cardiovascular diseases.
Trans fats should be avoided where possible, and overall, about 30-35% of your daily calories should come from healthy fat sources.
Working out how you should split your Macro-nutrients.
There are a few ways you can work out how to split your macro-nutrients, depending how accurate you want it to be and how much time you want to take. The simplest way is to use your hand as a guide.
For women, your palm is the size of the protein portion you should have at each meal, one fist sized portion of vegetables, one cupped-hand portion of carbohydrates (excluding vegetables), and one thumb sized portion of fats, and you should have 3-4 meals per day. See the image below for a visual explanation, along with guidelines for men.
However, if you want to be more accurate and track/weigh your food, then the calculations below should be performed. The energy you get from each type of macro is required for this calculation, and is as follows:
- Carbohydrates: 4 kcal per 1 g
- Protein: 4 kcal per 1 g
- Fat: 9 kcal per 1 g
Based on weighing 50kg, having a BMR of 1250, and being active so having a daily target of 1.4×1250=1,750 to maintain weight, or 1,250 for 0.5kg loss per week (see Calories and BMR blog for more details on how to work this out):
Fat 30% of daily calories (stated above) = 375kcal
Fat in grams = 375/9 = 42g
Protein minimum 1g per kilo (stated above) = 50g
Protein minimum as kcal = 50×4 = 200kcal
Protein maximum 2g per kilo (stated above) = 100g
Protein maximum as kcal = 100×4 = 400kcal
Carbohydrates therefore make up the rest:
With protein at minimum, calories left are 1,250-375-200=675kcal
In grams, this works out at 675/4=169g
With protein at maximum, calories left are 1,250-375-400=475kcal
In grams, this works out at 475/4=119g
So, the macros are:
Fat 42g (375kcal)
Protein 50-100g (200-400kcal)
Carbohydrates 169g-119g (675-475kcal)
These can be converted to percentages to input into a tracking app such as My Fitness Pal if necessary.