The number and distribution of your meals will not impact fat loss or muscle gain in a significant manner, but what and when you eat can potentially impact your performance and/or recovery if you’re an athlete. Let’s talk about why...
Fat Loss
You may have heard that eating more meals will “stoke the metabolic furnace” and lead to greater fat loss—but this simply isn’t true! Eating more meals will not increase your metabolic rate.
The amount of energy it takes to digest and absorb food, called the thermic effect of a meal, will average right around 10% of the calories you eat in that meal. So, if you eat 2000 calories per day, you’ll still burn a total of 200 calories to metabolize that food whether it is broken up into two meals or six.
Remember, whether someone loses or gains weight is dictated by total calorie intake, not the timing of food intake. The most important factor determining your success will be just to hit your calorie and macros for the day.
Muscle Gain
Each time you eat a 20-40 gram serving of protein, you maximally activate muscle-building pathways. For this reason, it would be logical to think that eating frequent high-protein meals would give you a muscle-building advantage. Over the short-term, this appears to be true, but long-term studies don’t seem to show any significant difference when total protein intake is divided over 2 or 3 meals versus 5 or 6.
That being said, it’s very hard to carry out well-controlled long-term studies in the real world while also accurately detecting the very small changes in muscle mass that might be a product of protein distribution. So, while there theoretically might be a negligible advantage to eating 4 or 5 high protein meals per day (say 0.5%) that might be valuable to bodybuilders and serious athletes, this almost certainly isn’t worth stressing about for most people.
When Nutrient Timing CAN Matter
Nutrient timing can be somewhat more important in athletes or serious exercisers, as particular attention should be paid specifically to ensuring enough carbs are provided before a workout, as well as after to replace glycogen (stored carbs around muscle) if a person is doing multiple workouts per day. The quality of your workout and how well you recover largely depends on how well you fuel and replete your body, and this can have an impact on performance and even body composition to some extent over the long-term.
While there may not be a huge advantage to eating regular high-protein meals, if you’re looking to optimize muscle building at all costs, it’s a good idea to consume 20-40 grams of protein before, during, or after a workout and in regular intervals throughout the day (every 4-5 hours that you’re awake).