So nutrition is a minefield right? You can find a study, an article, a blog post, a YouTube video or social media guru who will convince you that any diet is the right one. The truth is nutrition is an incredibly personal and individual thing and you need to find what works best for you, fits your lifestyle and is sustainable. There are however a few things that science makes facts! One of those things is the ‘calorie’. Today Sam Parker, currently studying an RSPH Level 4 in nutrition and a diploma in culinary medicine lays out the facts on calories. Read, digest (pun intended) and take away what you will.

“I am studying nutrition and my brain is always full of how the body uses food, the calculation of PAL and BMR, the thermic effect, blah blah, I’m just a big fat food nerd. Then at the box the other week I heard a statement that got my cogs really working.

“A Calorie is just a calorie right?” A fair assumption, but is this just that, just an assumption or is this fact.

I’m going to try and address the statement.

Er yes in terms of the amount of calories you eat and no in terms of the type of calories you eat, yep sorry not helpful.

Let’s break this down……

The science, a calorie is the energy needed to raise the temperature of one gram of water by one degree Celsius. (What)

Or how about some Maths.

Carbohydrate has 4kcal per 1g

Fat has 9kcal per 1g

Protein has 4kcal per 1g

Alcohol has 7kcal per 1g

Ah ha, getting somewhere, so not all calories are equal in a Maths equation.

Fact! If you eat more calories than you burn you will put on weight, no matter what the calories are made up of. However, if you eat the correct amount calories for your weight, age and activity levels the type of calories does matter as you will recover quicker, have a better immune system, you’ll have more energy, your organs will work efficiently and you will build more lean muscle mass, therefore, you can hit those AMRAPS with more vigor and lift a ton more weight. (Eating too many calories or too few calories is a whole other topic).

Therefore, calories are important but the type of calorie you consume is of the upmost importance.

Calories come from the food and drink we consume and food and drinks are made up of macronutrients (Carbohydrate (carbs are types of sugars), Protein and Fat) and micronutrients (vitamins, minerals) fibre and water. A calorie (Kcal) is the energy used to fuel your body’s brain function, vital organs, immune system, waste system, and used for repair and growth and also fuels any physical activity.

What are Macros

A Macro is the main type of food that we consume that provides the body with fuel to survive.

Protein  provides energy but also provides the body with the necessary tools to repair connective tissue and ensure the body’s fibres move efficiently. Protein regulates body processes such as the transportation of nutrients, it moves oxygen around your body, ensures your blood clots (plasma protein), forms bone, cartilage, protects your organs and grows muscle. Protein calories are less fattening than calories from carbs and fat as the protein takes more time to digest and metabolise into the body, they are also more satiating which tells the brain you are full. Win!

Fat provides energy and is stored as a reserve, fat is essential for our body as fatty acids provides insulation to your vital organs, fat is a major structural part of our cell membranes and is used to transport vitamins around the body and also keeps our skin from evaporating water.

Types of fats

Omega 3 and Omega 6 are vitally important for the heart, reproductive, immune and nervous systems and also the repair and manufacture cell membranes. On top of this, essential fatty acids also regulate inflammation, regulate body temperature and waste production and help our muscles contract.

Fat is essential to our body’s efficient function so do not cut it out of your diet hoping to drop some weight, this can be dangerous to your overall health.

Fats are more calorific (1g = 9kcal) so watch your consumption of good fats (nuts, diary, avocado, olive oil, meat, oily fish and eggs) and reduce or do not consume the bad fats (trans fats) found in margarine, fast food, ready meals and commercially fried/ baked goods.

Carbs at the main energy source for the body especially if you exercise as Carbs can be quickly absorbed and converted into energy. However, Carbs are sugars and care should be taken over how much and what type you eat.


Simple carbs are easy to digest and raise blood sugar levels quickly and tend to be low in fibre. As the body can only store so much energy at one time the excess energy is stored in reserve as trigylcerides (a type of fat lipid). If simple carbs are over consumed over time the body loses its ability to know when it has consumed enough energy from carbs. This is known as insulin resistance and can lead to Type 2 Diabetes.


Complex carbs are harder to digest and raises the blood sugar slowly keeping you fuller for longer. The insulin hormone is not triggered as much and the energy is slowly moved to where it is needed rather than spiking the insulin hormone to create excess energy. Complex carbs are wholegrains, vegetables, beans and sweet potatoes.

Alcohol has NO nutritional value so if you eaten your calories for the day then the energy from the kcals in alcohol is stored in your lipid tissues as fat – hello beer belly anyone.

Its’ fun and good for your social wellbeing, but that is it on a nutritional level. Sorry!

What are Microvitamins and Minerals

Vitamins and Minerals

Veg and Fruit is essential in your diet to assist the macros do their jobs, micronutrients transport the macros around the body. Each micronutrient and mineral does a different job so a diet full of different vegetables is important for your fibre intake (gut health), to fight free radicals (cancer cell killing and heart health) and for cell repair and maintenance (carrots helping your eye health is a real thing).

Watch out for fruit and fructose sugars, if you have type 2 diabetes or are pre diabetic watch your consumption as the fructose sugars will trigger the insulin hormone and provide your body with too much energy (like simple carbs). Load up on loads of veggies to ensure you get all your vitamins.

Thermic effect of food

If the pathway that the food is metabolized through is more efficient the quicker the food is digested i.e. simple carbs, Protein’s pathway is less efficient and takes the body longer to digest, as the protein is digested heat is created in the body which burns off the calories as it is metabolized, ever had meat sweats! So more energy to digest equals less calories in the body to be used, or stored, as energy.

Your body metabolises (burns) calories from Fat, Carbs and Protein at different rates. With Protein burning more calories than fat and carbs which makes protein less calorific gram for gram than the other macros.

For instance, 100 calories protein is reduced to 75 calories for the body to use and 100 calories of fat is reduced to only 98 calories for the body to use.

The foods that take more calories to burn are called high satiety foods, for instance, beef, eggs, beans and chicken, and low satiety foods, which burn less calories when they are digested, include foods made of refined sugars and simple carbs.

In short 500 calories of jam donuts are super tasty but are only going to send your insulin hormone wild and cover your face in refined sugar, whereas, 500 calories of chicken, sweet potato and green veg is going to fuel you through your workout and help your body recover and build some muscle gains.

So no, this was a long-winded way of saying a calories isn’t just a calorie.

To summarise:

Make sure you eat protein, a small amount of healthy fat and complex carbs (lots of veg) and fibre with each meal. Keep your consumption of alcohol, sugars and trans fats to a minimum and drink plenty of water and you will be on track for a healthier diet.”