“You may lose or gain weight by manipulating your carb consumption but there’s a lot more to it than meal timing…”
The role of carbohydrates are often misunderstood in regards to how it can change our body composition. I shake my head each time I hear a personal trainer give misinformed advice about the significance of eating carbs at night. You may lose or gain weight by manipulating your carb consumption but there’s a lot more to it than meal timing. Once you start to properly understand how your body works it becomes easier to make the necessary changes to keep progressing with your physique. I love a big bowl of porridge oats not too long before I sleep. I find that it keeps me satiated through the night. If I was to gain weight I would not attribute it to this meal in isolation, but to the accumulation of the other calories I ate prior to this meal also.
People often believe that it is harder to use carbs as a fuel source at night because of a slowdown of your metabolism when you sleep. So any carbs you eat during this period will convert to fat. There are also suggestions that insulin sensitivity is lower at night so it’s better to avoid carbs for this reason as well. Hopefully by the end of this article you will start to think differently.
Dispelling the myth
Energy expenditure and carbs Our body uses energy in a variety of ways. Our resting metabolic rate (RMR) is the energy needed to make sure everything functions properly internally. About half of our daily energy expenditure is for our RMR. Our RMR still uses up a lot of calories whether or not we are active. The energy we use for exercise is the exercise activity thermogenesis (EAT) and the energy we expend for all other physical activity called our nonexercise activity thermogenesis (NEAT).
Energy is also expended on the thermic effect of food (TEF) but is smaller quantities than the other processes. Protein has the highest TEF so that’s one of the reasons higher protein diets are great during a fat-loss phase. The myth would suggest that our RMR would decrease when we sleep because our expenditure is lower than during the day.
We will not be exercising or doing any other activity when we’re sleeping (unless you sleepwalk!) so our EAT and NEAT do not need to be considered in depth here. Studies have found that our RMR is not significantly different when we sleep than during the day. If this is the case, eating carbs at night will not cause an increase of fat gain compared to if you eat those same carbs throughout the day.
The main cause of body composition change is the total caloric intake for the day. Staying in a daily calorie deficit (eating less than your weight maintenance calories) will result in fat-loss over time regardless of the timing of your carb consumption. On the flip side, if you eat in a calorie surplus you will still gain weight even if you refrain from eating carbs at night.
We will end up using our stored energy the following day even if we do not use it all up during the night. As long as you refrain from consuming too many calories you should not gain weight. This may surprise you but dietary carbs are not easily converted to fat. It is rare that excess carbs are turned directly into fat through a process called De Novo Lipogenesis. Dietary carbs are used as glycogen in our muscles, liver, and as a source of energy. If you eat an excess of carbs while being in a calorie surplus, this will cause your body to readily store ingested dietary fat as body fat.
This is due to fat oxidation being suppressed by the carbs eaten. An overtly high calorie diet full of carbs and fat is recipe for disaster if your goal is to maintain or lose weight. It is the combination of too many calories, carbs, and dietary fat that will results in fat gain. Carbs on their own are not the cause.
Our pancreas creates the insulin hormone to control our blood sugar. When our cells are more insulin sensitive, sugar is more easily removed from our blood and moved for storage. Being more insulin resistant causes our body to be less able to effectively use carbohydrates. This could lead to higher levels of fat storage. Having chronically high levels of blood sugar can also lead to health problems such as heart disease and diabetes.
If our insulin sensitivity was truly lower at night then eating your evening carbs could also lead to increased fat storage. Studies have shown that insulin sensitivity is consistently the same in the afternoon and evening. So it really is not a big deal in regards to insulin sensitivity to eat more carbs later in the day. You can improve insulin sensitivity in the long term by training consistently and controlling your diet. This should be the focus of concern as opposed to simply trying to cut carbs at night time.
If you saved all of your calories for the evening you would still not gain weight as long as you were in a calorie deficit for the day overall. People that follow intermittent fasting would swear by this and only allow themselves to eat within a given time frame for the day. When it comes to fat-loss and meal timings you want to choose a method that helps you stick to your calorie and macro nutrient target the most. I personally like to eat 5 smaller meals each day that amount to my total caloric needs.
I find this suppresses my appetite the most effectively. If you do not feel hungry in the morning but usually get hungrier as the day wears on, you might want to consider fasting in the morning and then saving your calories for later in the day. This way you can eat larger meals without exceeding you daily food target. Your body is not a fat storage machine at night so there’s no need to treat it like one!