What are calories?
Calories (Kcals) are simply an expression of energy in our food, scientifically illustrated it's the amount of energy required to raise the temperature of a litre of water by 1 degree celsius.
Why do you need them?
I often get frustrated when I hear people compare their body to a car. yes, a car requires fuel as does your body BUT (and it's a big BUT!) when you turn off a car engine it stops burning fuel. Your body is different, it's burning fuel from the moment you were conceived until you die, regardless of additional energy expenditure. This means that even if you were to sleep for the next 7 days your body still requires lots of energy to breathe, for your heart to beat, to support restoration and for your organs to function (this basic calorie requirement is known as your basal metabolic rate or BMR).
What is Metabolism?
In simple terms metabolism is the rate at which your body converts fuel into energy for use (metabolic rate).
What influences my metabolic rate?
Many factors influence metabolic rate, including
- Muscle mass
- Illnesses or disease
- Level of activity
- Environmental temperature
- Thermic effect of food
- Body composition
The maths, How many calories do I need?
These days there are many apps and websites which offer calculators, the problem with this is you never know how the figures are generated. I would suggest using the formula below:
The Schofield Calculation:
18-29yrs BMR= 15.1x weight (KGs) + 692 SEE= 156
30-59yrs BMR= 11.5x weight (KGs) + 873 SEE= 167
18-29yrs BMR= 14.8x weight (KGs)+ 487 SEE= 120
30-59yrs BMR= 8.3 x weight (KGs)+ 846 SEE= 112
SEE (Standard error of estimation: The calculation may be too many or too few by this amount).
BMR x1.4 inactive men and women (this applies to most people in the UK)
BMR x1.6 moderately active women
BMR x1.7 moderately active men
BMR x1.8 very active women
BMR x1.9 very active men
THE SIMPLE WAY (Bagley 1996; Glynn et al 1999):
BMR = 25 kcals/kg body weight
I want to lose weight, can I simply slash my energy consumption and lose weight?
Energy consumption should not be slashed in order to lose weight it should be reduced in a measured way which will vary from one person to another. Simply eating 500 Kcals per day will not work, this is well below BMR for a human regardless of the variants above (the only people that can recommend this sort of action is a nutritionist, dietitian or suitably qualified health care practitioner). Eating too few calories for a long time will cause a number of issues:
-Fatigue: Tiredness, No fuel in = unable to expend energy.
-Mood swings: feeling deprived, unable to concentrate, twitchy.
-Hormonal in balances: Not having enough energy from calories causes confusion in homeostasis (your natural chemical seesaw). Particularly Leptin (the hormone that tells you when you are full up) and Ghrelin (which tells you when you are hungry).
-Reduced metabolic rate: A confused body without fuel has no idea where it's next energy is coming from so stores some energy in case it goes into stress or an adrenal/ shocked state (over time this becomes an issue called adrenal fatigue AKA metabolic damage).
-Undernourished: Eating way below caloric requirement is likely to mean you just aren't eating enough, variety in the diet is lacking, which means you aren't nourishing your body.
So how do I lose weight?
Create a reasonable calorific deficit, generally 10-15% lower than your calorie requirements. This must be done, carefully. Starting a "diet" on Monday and hoping to lose 16lbs by the weekend, simply isn't reasonable. PLEASE NO MORE SETTING YOURSELF UP TO FAIL.
"PIGEON STEPS WILL CONQUER EVEREST with consistency!!!!"
What should I do if I am currently eating well under my calorie requirements, and trying to lose weight?
Many of our clients here at Three Pillars of Fitness require help with metabolic repair, this is a really difficult principle to accept "YOU AREN'T EATING ENOUGH TO LOSE WEIGHT!!" Many clients who fall into this category are also exercising, really hard. In this case we work really closely to coach a new mentality towards health: MIND: DIET: EXERCISE. A plan consisting of 6-8 phases is developed according to the individuals requirements, beginning with reducing exercise and slowly introducing more nourishment, energy and calories. If you are struggling to understand your energy requirements, reach out and book yourself a FREE CONSULTATION by clicking here.