You know that protein is an essential macronutrient in your diet. You may also know that the amino acids in protein are the building blocks of muscle, helping you recover post-workout. But there’s another benefit that’s rarely talked about: protein keeps you feeling fuller for longer, helping fight off those afternoon cravings and lowering your appetite.1,2
This blog is not intended to be a weight-loss management guide. Instead, we look at how athletes use a protein-rich diet to maintain a competitive weight because, depending on the sport, there may be strict guidelines they have to follow.
The experts at Ascent answer all your questions about how exactly protein keeps you full and tips to amp up your intake throughout the day.
Which protein will make you feel full?
Not all protein is created equal. Depending on the source, protein may differ in levels of appetite suppression and rate of absorption. A study by the British Journal of Nutrition examined the components of dairy protein, a common protein source, and its effects on appetite. The results revealed that since whey is fast-digesting and casein is slow-digesting, whey protein will make you feel fuller immediately following your meal.3
Another study analyzed the hunger of healthy, normal-weight women after ingesting whey protein. The subjects reported increased feelings of fullness, especially compared to carbohydrates and subsequently ate less during their following meals.4
Let's remember that protein is only one part of a healthy diet. Make sure to include fiber-rich fruits and vegetables, healthy fats, and plenty of filtered water to complete the picture of a satisfying and nourishing diet.
How does protein lower your appetite?
It’s well known that protein is more satiating than carbohydrates. But why exactly? Each macronutrient affects your body differently and in powerful ways you may not realize. Research on whey protein show that the higher levels of glycomacropeptide (GMP) in whey stimulate cholecystokinin (CCK), a gut hormone that signals satiety in our brains.5
There’s also evidence that the peptides released upon digestion and the amino acid composition in proteins such as whey may be related to why we feel satiated after eating them.4
So the next time you reach for a muffin for breakfast or cheese pizza for dinner, remember that you might be hungry again in no time. Instead, go for a protein-rich meal the first time around, and you'll stay satisfied longer.
How can I add protein to my diet?
There are a variety of easy ways to add protein to your diet. The first step is ensuring that breakfast, lunch, and dinner each contain 25 grams of protein, then adding protein-rich snacks throughout the day. Start with whole foods, such as chicken, salmon, grass-fed beef, eggs, nuts, lentils, and broccoli. Then supplement with whey protein powders to reach your goals.
Starting your day with protein is a great way to keep you satiated throughout the day. We recommend our Overnight Oats or Protein Smoothie recipes in the morning for an ultra-convenient way to increase your daily intake.
Lastly, since a fitness routine is likely a part of your healthy lifestyle, we recommend including a whey protein powder after your workout to refuel and maximize athletic performance and muscle recovery.
Do you still need a bit of inspiration? Check out our recipes page for crave-worthy meals and snacks that are delicious and packed with protein.
- (“Effect of dairy proteins on appetite, energy expenditure, body weight, and composition: a review of the evidence from controlled clinical trials | American Society For Nutrition”, 2013)
- (“The Effects of Consuming Frequent, Higher Protein Meals on Appetite and Satiety During Weight Loss in Overweight/Obese Men | Obesity (Silver Spring)”, 2011)
- (“Casein and whey exert different effects on plasma amino acid profiles, gastrointestinal hormone secretion and appetite | British Journal of Nutrition”, 2002)
- (“Effect of whey protein and a free amino acid mixture simulating whey protein on measures of satiety in normal-weight women | British Journal of Nutrition”, 2016)
- (“Effect of time of consumption of preloads on measures of satiety in healthy normal weight women | Elsevier, Appetite”, 2012)