Eating Carbs and Fats Together for Optimal Benefits
Nutrient partitioning (also called nutrient timing or meal timing) is the careful scheduling of macronutrient intake to support weight loss, fat loss, or bodybuilding goals.1 Athletes who use this dietary strategy plan exactly when they eat carbs, protein, and fat to take full advantage of the nutritional advantages of each.
People who are trying to lose weight may use meal timing strategies to help them stick with their eating plan. Not all experts agree on the value of nutrient timing for fat loss or muscle gain. In fact, the research shows some promise but also indicates mixed results.
Nutrient Timing and Exercise
If you are a regular gym-goer, you may have noticed weight lifters grabbing a protein shake within minutes of finishing their session. Many times, the shakes include supplements (like herbal compounds) or other ingredients to boost the benefits of macronutrient partitioning.
The word “partitioning” is used to describe this food timing practice because scheduling your intake of protein and carbs may influence how the nutrients are used or “partitioned” in the body.
People who practice nutrient timing believe that consuming certain nutrients at specific times promotes insulin regulation for fat loss and muscle building. For example, you might consume a carbohydrate and protein-rich meal or snack right before exercise or immediately after exercise to increase insulin production.
The theory is that by elevating insulin levels, you boost glucose uptake in the muscles which builds and repairs muscle that is broken down during your workout. While some research supports timing your macronutrient intake, other studies have found no advantages to meal timing.
One large review of studies concluded that there is evidence to support eating protein within a certain timeframe, but not carbohydrates.2 The researchers stated that “high-quality protein dosed at 0.4–0.5 g/kg of lean body mass at both pre- and post-exercise is a simple, relatively fail-safe general guideline.”
They added that the timing of carbohydrate intake is less important, as long as you meet your daily requirements.
Nutrient Timing vs. Nutrient Balance
Carefully monitoring of what and when you eat can be a lot of work. For many people, simply eating a balanced diet is difficult enough. Is it really necessary to practice nutrient timing as well? The answer depends on your goals. Many experts say that getting a proper balance of nutrients is more important than food timing practices. As a result, macronutrient partitioning may be more trouble than it’s worth.
Leisan Echols, MS, RDN, CSSD, CSCS, advises that the timing of specific nutrient intake should be reserved for only those who are serious about their fitness level. “As a board-certified specialist in sports dietetics, the majority of my clients range from avid exercisers to elite athletes. Achieving optimal body composition, modifying weight (loss or gain), and/or improving performance are typical goals,” she says.
“With that said,” she continues, “for my clients, I feel that timing and absolute daily intake of nutrients are equally important. For inactive individuals, I believe absolute daily intake of nutrients is more important than meal timing.”
Avid exercisers, performance athletes, and bodybuilders may benefit from the benefits of nutrient timing. For these individuals, investing more time and effort into their athletic endeavors makes sense.
For many of us, however, scheduling the intake of each nutrient is more work than we need to put into our diets. Simply getting the right balance of nutrients at mealtimes is enough of a challenge. We may be able, however, to benefit from scheduled meal timing if weight loss or healthy weight management is a goal.
Meal Timing for Weight Management
If you’re trying to lose weight and following a calorie-controlled diet, timing your food intake may provide additional benefits. In fact, research has suggested that scheduling your food intake to eat more in the morning may offer a small boost in your results.3
One 2013 study of 93 sedentary overweight and obese women with metabolic syndrome found that front-loading calories by eating a larger breakfast, followed by a smaller dinner, was more effective for weight loss than doing the reverse (eating a smaller breakfast and larger dinner).3
Women who took part in the study ate 1,400 calories per day and maintained a sedentary lifestyle for the duration of the trial. The study authors concluded that “high-calorie breakfast with reduced intake at dinner is beneficial and might be a useful alternative for the management of obesity and metabolic syndrome.”
Echols has also seen benefits with her weight loss clients who use meal timing. She says that when she creates a specific meal and snack schedule for her clients, it provides the guidance they need to be successful.
“Having the structure of a meal plan makes eating well less stressful. Not only do [clients] know when to eat, they also know how much and what types of foods to eat to get the right balance of protein, fat, and carbohydrates.”
Echols adds that there is no perfect meal timing schedule for everyone. Your perfect food schedule may be unique to you. “It depends on the individual and many additional factors,” she says. Factors that can come into play include your physical activity level, the type of exercise you participate in, the duration of your physical activity, and even genetics.
Specific nutrient timing has the potential to provide benefits for weight loss and athletic performance. However, these benefits are probably minimal for the average person. If your goal is weight loss, eating certain foods at specific times won’t compensate for a diet that is unbalanced or too high in calories.
If your goal is to improve your athletic performance, nutrient partitioning can’t take the place of a consistent, well-designed training program, but it may prove some benefit. In short, food timing helps you fine-tune good nutrition, but it doesn’t take the place of a balanced eating and exercise plan.