Whether you want to lose weight or gain it, a diet with an adequate amount of protein is key.

The Dietary Guidelines for Americans suggest your daily calories should consist of:

  • 10 to 35 percent of protein
  • 45 to 65 percent from carbohydrates
  • 20 to 35 percent of fat

The recommended daily allowance of protein is 0.8 grams per kilogram of body weight. Research suggests, though, that athletes benefit from more protein to maximize muscle growth. Those who frequently and consistently lift weights or do resistance training may benefit from consuming 1.3 to 1.8 grams of protein per kilogram of body weight per day.

That means that an active 180-pound male should consume about 106 to 147 grams of protein a day for muscle growth. An active 140-pound woman should consume between 83 and 114 grams of protein per day.

Is there an optimal time to consume this protein? While hitting the overall daily intake is most important, research does suggest that protein timing can make a difference.

Studies are mixed about whether consuming protein immediately after a workout has a beneficial effect on muscle growth. Several studies do show that protein consumed before bed can indeed foster muscle growth.

Protein supplies amino acids, which build our muscles. Our muscles repair themselves and grow while we sleep. Growth hormone is elevated during this time. This hormone boosts muscle growth and decreases fat.

Studies have shown that if you consume an ample amount of protein right before bed, you’ll take full advantage of this spike in growth hormone and maximize muscle gains. This happens because you’re providing the amino acids that are needed for repair and growth.

A 2012 study assessed the effect of eating protein before bed with 16 healthy young male participants. They performed a single bout of weightlifting in the evening and were provided 20 grams of protein immediately after exercise. Thirty minutes before sleep, eight of the men ingested a beverage with 40 grams of casein. Muscle protein synthesis rates were increased in the eight men who consumed the casein beverage before bed. This provided evidence that protein increases postexercise overnight recovery.

Another study from 2015 monitored 44 young men as they completed a 12-week resistance training program. All participants consumed a high-protein diet (1.3 grams of protein per kilogram of body weight). One group consumed a drink before bed containing 27.5 grams of protein and 15 grams of carbohydrates. The other group received a placebo drink. The group who consumed the protein drink saw greater improvements in muscle strength, muscle size, and muscle fiber size.

However, both of these studies had limitations. It’s not clear in both studies whether the increase in total daily protein intake or the protein intake specifically before bed resulted in muscle gains.

However, the overall body of research on protein intake and muscle growth has led the International Society of Sports Nutrition to take the stance that “casein protein (~ 30-40 g) prior to sleep can acutely increase MPS [muscle protein synthesis] and metabolic rate throughout the night.” They recommend nighttime protein intake for athletes who train in the early morning without eating, or in the evening after dinner.

And in a different 2015 study comparing carbohydrate snacks verses protein snacks before sleep, the protein group had improved metabolism.

A 2011 study explored the loss of muscle mass with age. Sixteen “healthy elderly men” participated in the study. Eight ingested casein, a slow-digesting protein, before bed. The other half had a placebo. Those who consumed casein protein showed a more positive overnight whole-body protein balance. This means that dietary protein before sleep promoted muscle growth, even in older and less active people.

However, other recent research shows that in sedentary, overweight individuals, a snack before bed increases insulin levels the following morning. This could potentially lead to more weight gain. This appears to be true of both protein and carbohydrates. Therefore, the benefits of a nighttime, pre-sleep protein snack are best seen in athletes, daily exercisers, or the elderly.

If you’d like to boost muscle growth during sleep, what should you eat? An average adult should aim for something with about 10 to 20 grams of protein.

Good sources of protein include:

  • poultry
  • fish and seafood
  • tofu
  • legumes, lentils, and peas
  • Greek yogurt, cottage cheese, and ricotta cheese
  • eggs
  • nuts

About 3 ounces of chicken, salmon, 90-percent lean ground beef, or 1 cup of cooked beans or lentils will help you reach a 20-gram protein mark. Some appropriate high-protein snacks include:

  • 1 cup of 1 percent milk fat cottage cheese
  • one slice of bread with peanut butter and a glass of 1 percent milk
  • a single-serving container of plain Greek yogurt with berries
  • three hard-boiled eggs

High-protein recipes

While protein powders, shakes, and bars may also provide an adequate amount of protein, it’s preferable to consume “real” food instead at most meals.

These supplements don’t offer the same nutrients as whole foods like lean meats, eggs, or yogurt. They’re also often packed with sugar or artificial sweeteners and may be high in calories. What’s more, supplements aren’t strictly regulated by the U.S. Food and Drug Administration. That said, the studies mentioned above did use protein supplements, not mixed protein meals.

If you have trouble meeting your daily recommended caloric or protein needs, a protein shake could be a good option. The U.S. Department of Agriculture recommends about 2,600 calories a day for a moderately active man and 2,000 calories a day for a moderately active woman for weight maintenance. If you’re aiming to lose weight, your calorie needs will be lower.

If you’re looking to encourage muscle growth from your workouts, consider adding protein to your late-night routine. By providing the amino acids that your muscles need to repair and rebuild during sleep, you could make gains while you snooze.