You’ve probably heard friends who are dieting and into health and fitness mention ‘macronutrients’ or the shortened abbreviation – ‘macros’. But what are macros and how does different macronutrient ratios impact weight and health?



fats, protein and carbohydrates make up macronutrients

Macronutrients are divided into the three main nutrients that make up the food we eat. The body needs these nutrients to survive. The three main nutrients are carbohydrates, fats and protein.


carbs are not created equal

Carbohydrates are the main source of energy for the body. They are sugar molecules and are found in many foods including bread, pasta, rice, potatoes, broccoli, carrots, fruit, biscuits, cakes and cereals. Carbs are called carbohydrates because at a chemical level, they contain, carbon, hydrogen and oxygen and are the body’s preferred energy source.

Carbohydrates are split into two groups, simple and complex.

Simple sugars are molecules of carbs that contain one or two molecules called saccharides (mono or disaccharide). These simple sugars allow the body to absorb them quickly. The sweet flavour of simple sugars makes it easy to over consume which adds to weight gain.

Examples of simple sugars are sweets, cakes, biscuits, fizzy drinks, fruit juices, smoothies, cereal bars, breakfast cereals, maple syrup, table sugar, honey, dried fruit, ice cream, sports drinks, milk, fruit and condiments, such as ketchup.

Obesity, diabetes, heart disease and cancer have all been associated with a high dietary intake of simple sugars. Read previous blog on 5 tips for sustainable weight loss.

  • A caveat about whole fruit intake. Whole fruit is an excellent source of nutrients, providing water, fibre, vitamins and antioxidants. These intrinsic sugars naturally occur in fruits and vegetables and are not the sugars we need to be concerned about.

Complex sugars/carbs contain three or more linked molecules of sugar and are called polysaccharides. These long saccharide chains are also known as starches and take longer to break down in the body. Some of the best complex carb sources come from sweet potatoes, quinoa, oats, buckwheat, chickpeas, spelt, butternut squash, whole-grain bread, brown rice, wild rice and lentils.

Complex carbs are high in energy, vitamins, minerals and fibre and gives greater satiety than simple carbs.

How many carbohydrates per day?

The Government Dietary Recommendations for the average man is 333g with 33g coming from free sugar. For women, it’s 267g with 27g from free sugar (note that free sugar is added sugar. Sugar from whole fruit and vegetables have fibre to slow the digestion process and are not classified as free sugar. Milk has proteins that slow the digestion process and therefore is not classified as free sugar).

To work out how many calories are in 333g of carbs, multiply 333 by four. Why four?

Every gram of carbohydrate contains four calories. Therefore, 333g of carbs equates to 1332 calories and no more than 132g should come from free sugar. For a woman, carbohydrate intake per day according to the GDR is 1068 calories and no more than 108 calories from free sugars.

These values are based on 2500cal/day for males and 2000cal/day for females.

For fat loss, I suggest a smaller proportion of your macronutrients should come from carbohydrates.

Based on 2500cal/day for a man and 2000cal/day for a woman.

  • MALES – 250g (1000 calories) of carbohydrates and no more than 25g (100 calories) from free sugars
  • FEMALES – 200g (800 calories) of carbohydrates and no more than 20g (80 calories) from free sugars

E.g. – 250g of carbohydrates: Bowl of porridge oats (40 g), medium banana (20g), 2 slices of brown toast with butter (40g), serving new boiled potatoes (20g), 200g of pasta (50g), cup of carrots (25g), corn on the cob (30g), 2 chocolate biscuits (25g)

how much fat?

limit saturated fats, eat unsaturated fats and avoid trans fats

Fats give you energy, protects your organs, supports cell growth, keeps cholesterol and blood pressure under control and helps your body absorb vital nutrients and certain vitamins. However, fats aren’t made by the body and have to be consumed.

Fats in foods include dairy, meats, poultry, seafood, eggs, nuts, seeds, avocados, coconuts, oils and fast food.

There are three types of fats:

  • Saturated fats are hard at room temperature and found in the greatest amounts in dairy and animal products, coconut, cakes, biscuits, chocolate, crisps, pizza, sandwiches and most fast foods. Saturated fats are best limited in the diet as high levels can raise LDL causing high cholesterol, heart disease and cancer.
  • Unsaturated fats (monounsaturated and polyunsaturated) increase your good cholesterol (HDL) and protect your heart while reducing levels of LDL in the blood. They are found mainly in olive oil, rapeseed oil, avocados, almonds, nuts, oily fish such as salmon, kippers, mackerel, sardines and plant seeds.
  • Trans fats, which is short for trans fatty acids occur naturally in some foods but are also artificially produced. Because trans fats are not healthy, responsible food manufacturers are phasing them out. But trans fats can still be found in some processed foods, such as cakes, biscuits, pies, chocolate bars, french fries, doughnuts, margarine, frozen pizza, coffee creamer and fried foods.
How much fat per day?

The Government Dietary Recommendations for the average man is 97g with 31g coming from saturated fats. For women, it is 78g with 24g from saturated fats.

Every gram of fat contains nine calories. Therefore, 97g of fats equates to 873 calories and no more than 280 calories should come from saturated fats. For a woman, fat intake per day according to the GDR is 702 calories and no more than 216 calories saturated fat.

These values are based on 2500cal/day for males and 2000cal/day for females. 

E.g. – 97g of fats: 2 scrambled eggs on toast with butter (30g), avocado (29g), KitKat Chunky (10g), packet of crisps (10g), one serving of mackerel (18g)

macronutrient protein

protein provides the body’s building blocks

Protein is made up of amino acids that are attached to one another in long chains called polymers. Proteins are broken down during digestion leaving behind amino acids.

The key functions of protein are growth, repair and maintenance of tissue and providing structure to the body.

Proteins also produce enzymes which allow key biochemical reactions to take place within the body and some proteins are hormones which act as chemical messengers between cells, organs and tissue.

Protein also regulates the concentrations of acids in the blood and other fluids and helps maintain a balance in the body.

Amongst many other vital jobs for the body, protein boosts the immune system and transports and stores vital nutrients and can be used as an energy source.

There are 20 different amino acids required for the body to function properly of which nine are considered essential. The essential amino acids are not synthesised in the body and must be obtained through diet. Nonessential amino acids are synthesised by the body.

9 essential amino acids:

Isoleucine, leucine and valine are known as the branched chain amino-acids (BCAAs). The molecular structure of these three amino acids includes branches, hence the name.

Branched-chain amino acids are essential nutrients that help support muscle metabolism and build muscle tissue.

Examples of foods which are high in protein are lean meats, poultry, seafood and fish, eggs and diary products, tofu, tempeh, edamame, lentils, beans, hemp seeds and green peas.

Daily protein intake?

The Government Dietary Recommendations for the average man is 55.5g. For women, it is 45g.

Every gram of protein contains four calories. Therefore, 55.5g of protein equates to 222 calories. For a woman, protein intake per day according to the GDR is 180 calories.

These values are based on 2500cal/day for males and 2000cal/day for females. 

For fat loss, I suggest an increase in protein intake compared with the GDR guidelines.

Based on 2500cal/day for a man and 2000cal/day for a woman.

  • MALES – 156g (625 calories) of protein
  • FEMALES – 125g (500 calories) of protein

E.g. – 156g of protein: 38g of vivo life perform protein shake (26g), 3 large boiled eggs (18g), 2 chicken breasts (70g), Tofu salad (35g), 50g of nut medley (7g)





Government Dietary Recommendations




Fat Loss Recommendations


Some weight loss diets recommend restricting carbohydrates to as low as 10-15% whilst upping protein intake to 40-50%.

However, the risks of using a high-protein diet with carbohydrate restriction may present health problems and is not recommended:

  • High-protein diets that restrict carbohydrate intake can result in nutritional deficiencies and insufficient fibre which can cause problems such as bad breath, headache and constipation.
  • Some high-protein diets include foods such as red or processed meat and full-fat dairy products which are high in saturated fats, may increase the risk of cancer, increased LDL and heart disease.
  • A high-protein diet may impact and stress kidney function which may cause issues with eliminating waste products.
  • Diets that are high in protein and meat may cause calcium loss. This is sometimes associated with osteoporosis and poor bone health.


Finally, it is important that you keep your calories to the recommended daily allowance for good health and body composition.

MyFitnessPal is an app to help you calculate your calories and macronutrients.

An average man should consume no more than 2500 calories per day and a woman no more than 2000 calories per day.  This may vary depending on age, height and activity levels. If your calories are too high, weight will increase regardless of macronutrient ratios.

A good method to find your correct daily calorie consumption is by calculating your basal metabolic rate (BMR).

BMR is the amount of calories required to sustain life. Then you add your daily activity levels.

Click here to find out your BMR.

Remember. A healthy outside starts with the inside. Healthy food, healthy life and don’t overdo it.

let what you eat heal you