Oh if I had a penny every time that I have heard this myth… I actually heard a nurse advising a patient this a few years ago when I knew nothing at all about food and nutrition. I cringed then.
Fats are one of the main macronutrients that make up our diet. None of the macros should be avoided, but the government recommends that we eat them in different proportions because they have different functions in our bodies and different effects on our health. Fat contains 9 calories per gram, which is the highest of all the macronutrients so it does makes sense to keep an eye on it when you’re trying to lose body fat. The UK government recommends that no more than 30% of our daily calories come from fats, but in the UK the current average caloric intake for fats is more like 42% of our diet. It is something that as a nation we need to make an effort to reduce.
Fat has different purposes in the body including protecting our vital organs, insulation, making the ’covers’ that go round our nerve cells and energy. It’s pretty important and by no means should it be cut out of our diets. When eaten to excess, fat is stored in the body. However, it is not as simple as you eat fat, it doesn’t get used so that same fat gets sent to the hips, stomach or wherever it is that you don’t like it being stored. In order to use fats, our body has to break them down. Fat molecules, or triglycerides (as 99% of the fats that we eat are this kind of fat) are too big to be absorbed and transported around the body, so they are broken down into their smaller components: glycerol and fatty acids. From there, they absorbed and end up in the blood stream where they are sent off to be used and the excess are then sent to the body’s fat cells (called apodicytes if you really want to know!) where the glycerol and fatty acids reform into triglycerides – so the fat that you store is made from all the different fats that you have eaten that day.
What about Carbohydrate and protein?
Both carbohydrate and protein if eaten to excess (and by excess I mean more energy is obtained by them than your body needs) will be stored as fat.
When your body has more carbohydrate than it needs, it will store some of it as glycogen in the muscles and liver. However, once these limited stores are full, then your body converts the carbohydrate into fat and stores it in the fat cells – it now has the same form that the fat that you ate and stored does. With protein, something similar happens. Excess protein cannot be stored in the body (although how great would it be if excess protein went to your glutes) so your body excretes the nitrogen it contains and converts the rest into energy. Like any other energy, and I’m sure you’re spotting a theme here, it is either used immediately, stored as glycogen or transported to the fat cells to be stored as fat.
When it comes to fat loss, the important thing is energy balance: calories in vs calories out. It is not fat or any one macronutrient which makes your body store excess fat but excess calories. Quite simply, if you eat more energy than you are using, your body will store it as fat.
I hope that this myth is well and truly busted! What health and fitness myths have you heard?