For years, we’ve been told to eat carbs in the morning because if we eat them later in the day, they’ll be stored as fat. Well, that’s not true.
Here’s the problem with eating carbs for breakfast. First, most carbs we associate with breakfast—like cereal, oatmeal, bagels, muffins, etc.—are quickly broken down into sugar upon digestion. This results in a surge of blood sugar, which stimulates your body to release insulin, one of your main fuel- (fat-) storing hormones. Not great if you want to lose weight.
Second, eating carbs in the morning disrupts your body’s natural circadian rhythm. Upon waking, cortisol levels are naturally supposed to be elevated. This prompts your body into action as this hormone ensures adequate blood sugar levels to start your day.
However, eating carbs early in the day blunts cortisol release since you’re already increasing your blood sugar by eating those carbs. Doesn’t seem like a big deal until you realize that over time, this upset of natural cortisol levels can lead to shifting circadian rhythms, which will only lead to further hormonal and fat-loss problems.
Instead, to keep your metabolism revved up and blood sugar and cortisol levels happy, it’s best to start your day with at least 20 grams of protein.