Do calories count?
In June this year I heard Dr Giles Yeo speaking about his book Why Calories Don’t Count. It was food for thought (pun intended!)
When it comes to food, calories are talked about a lot. A calorie count is given on the label of most packaged food, and new legislation will make it compulsory for restaurant menus to state the calories in their food. Yet there is so much more to food than calories alone!
So, what is a calorie? At its most basic a calorie is a measure of energy that can be used to measure any fuel - not just food. The method used to measure calories was pioneered hundreds of years and the tool used is a bomb calorimeter. To calculate the number of calories, in a fuel, the heat needed to raise the temperature of 1kg of water by 1°C is measured.
This is clearly very different to what happens in our bodies when we digest food. For one our core body temperature is steady at approx 37°C. We digest and metabolise what we eat to extract, not only energy, but also vital nutrients. On top of that each of us has unique and differing energy and nutrient requirements - our digestive systems are complex. New learning about the role of our gut, and the microbes that live there, is changing the understanding of what we need to be well and healthy.
There is another significant difference between a laboratory measure of a calorie and what our bodies do with food. What happens to protein, carbohydrate and fat, and how much energy is available, is not the same for each of these macro-nutrients.
Digesting what we eat takes energy. Protein takes the most energy to digest. The body breaks protein down into amino acids and for every 100 calories eaten as protein between 20-30 calories are used to digest it. Glucose is formed when the body breaks down carbohydrates. Your body needs 5-10 of every hundred calories to process carbohydrates, which include sugars and staches. Finally, fat; the body uses very little energy to process fat. With 97-100 of the calories in fat available as energy. So while calories can be counted the equation is not a simple as calories in calories out.
The diet industry has been built on calorie counting. Yet, as a measure of a healthy diet calorie counting is a blunt tool. A more intuitive way of eating, embracing variety and eating a diet rich in vegetables, fruits, nuts, seeds and wholegrains has many health benefits. Eating good food makes eating a joy, not an exercise in limiting or counting calories. The benefits of plant rich diet are many:
- freedom from calorie counting for a start,
- doing good for your long-term health,
- reducing the risk for developing a wide range of health conditions,
- as well as being good for the health of the planet.
Cooking for you is here to help you eat well. We provide tasty plant-based meals, when you want them. And you don’t need to be a non-meat eater to enjoy them, it’s about providing a choice and an easy way to get more variety in your diet.
Read and listen to more from Giles Yeo.