Your metabolism is the process by which your body converts what you eat and drink into energy that it can use. Even when you're at rest, your body needs energy for things like keeping your heart beating, managing hormone levels, digestion, breathing, repairing muscles, growing hair, and so on. This baseline energy requirement is what we call your metabolic rate and is measured in calories (the amount of energy released when your body breaks down food).
People who have a high (or fast) metabolism burn energy at a quicker rate than people with a low (or slow) metabolism, and so people with high metabolisms need more energy than their peers to undertake all their body functions. There are several factors that determine your metabolic rate, such as your body size, body composition, sex, age and genetics. You can increase your metabolism slightly through activities like muscle gain or healthier food choices, but the reality is your metabolic rate is pretty much preset and constant because it is mainly determined by genetics and therefore resistant to change.
As a rule of thumb, the recommended daily calorie intake is 2,000 calories a day for women and 2,500 for men. If you eat more calories than your metabolic rate requires then you will end up gaining weight as any excess calories consumed will be stored as fat, no matter how healthy your diet is. Conversely if you eat less calories than your metabolism requires you will end up losing weight. We will look at how you can calculate your total daily calorie target (“TDCT”) in a later blog. Once you have your total daily calorie target, you should start to think about the quality of those calories. Eating a hundred calories of vegetables will have a very different effect on your body compared with eating a hundred calories from candy, even though both carbs will provide you with the same energy.
Don’t forget you can use our app to calculate your TDCT.