Protein is very important for health. Protein is in every cell of our body. Getting enough protein can help with muscle mass (which can help burn calories), help with appetite control and help with weight loss. Also, after eating, protein has a higher thermic effect than carbs or fats meaning it raises your metabolic rate and helps you burn more calories.
The current recommended daily intake (RDI) for protein is 50 grams per day. However, there is evidence to show and many researches believe that people should really be eating more than this amount (1). There is evidence that consuming a moderate amount (25-35 grams) of high-quality protein during each meal stimulates muscle protein synthesis and promotes muscle health, and helps to preserve muscle as we age (1).
Many controlled studies have shown that the best way to achieve and maintain a healthy weight is by eating a high-protein diet (2, 3, 4, 5, 6, 7). In one study, for two weeks, subjects ate a weight maintaining diet (15% protein, 35% fat, and 50% carbohydrate), then a two week reduced calorie diet (30% protein, 20% fat, and 50% carbohydrate) and finally an ad libitum diet of (30% protein, 20% fat, and 50% carbohydrate) for 12 weeks. The diet with the best appetite control was the reduced calorie, high-protein diet. Overall, the study participants spontaneously ate about 441 calories less per day, lost about 11 pounds with 8 of these pounds from fat tissue (8). Protein reduces levels of the hunger hormone ghrelin, while increasing the fullness hormones GLP-1, peptide YY (PYY), and cholecystokinin (CCK).
So, if a high protein intake can help with muscle mass (which helps burn calories even when at rest), helps you feel full and eat less, and after eating it, you burn more calories compared to carbs and fats, you may be asking yourself, “How can I eat enough or eat more”? The answer is aim for about 30% (25-35%) of your total calories to be from protein and spread your protein intake out throughout the day by eating protein at each meal. For example, if you want to calculate 30% of your diet from protein, if you goal for calories is 1,200 per day, multiply 1200 by 0.075 = 90 grams. If your calorie goal is 1500 calories, multiply by 0.075 = 113 grams of protein per day. Then, spread your protein out between your meals and snacks if you include them.
Are all protein foods alike? Protein is made up of smaller building blocks called amino acids. Some of these amino acids are essential meaning that they have to be provided by our diet. Foods from animals such as meat, poultry, fish, eggs, and dairy have all of the essential amino acids we need to form complete proteins. Soybeans are also complete. Other foods such as grains, legumes, beans, nuts & seeds, vegetables and fruits do not contain all of the essential amino acids but if eaten in the same day, your body can form the complete proteins that it needs.
Ideas for pairing foods that make complete proteins:
Dairy with nuts/seeds and legumes
Grains with dairy
Legumes with grains, nuts, seeds or dairy
Here is a list of commonly consumed protein foods and their approximate protein content per serving listed from the United States Department of Agriculture, ndb.nal.usda.gov
|FOOD||Portion Size||GRAMS OF PROTEIN|
|Chicken, skinless, white meat||3 ounces cooked||28|
|Turkey, roasted||3 ounces cooked||25|
|Salmon||3 ounces cooked||22|
|Tuna||3 ounces cooked||23|
|Halibut and Cod||3 ounces cooked||19|
|Shrimp||3 ounces cooked||20|
|Lobster||3 ounces cooked||16|
|Steak||3 ounces coooked|
|Lean Pork||3 ounces cooked||22|
|Cottage Cheese||4 ounces (1/2 cup)||12|
|Greek yogurt, plain, low fat||6 ounces||17|
|Cheese (cheddar, mozerella)||1 ounce||7|
|Lentils||4 ounces (1/2 cup)||9|
|Garbonzo Beans||4 ounces (1/2 cup)||6|
For a comprehensive list of protein foods, check out the following link: http://www.todaysdietitian.com/pdf/webinars/ProteinContentofFoods.pdf
When estimating how much protein you are getting if eating lean meat, you can estimate 7-8 grams of protein per ounce. So, if eating a piece of meat about the size of a deck of cards, which is 3 ounces, you can estimate 21-24 grams of protein. The protein content of other foods varies widely so check out the web link above for more information.
Enjoy your protein and all of its benefits!
- Arentson-Lantz E, Clairmont S, Paddon-Jones D, et al. Protein: A nutrient in focus. Appl Physiol. Nutr. Metab. 40: 755-761 (2015).
- Tang M, Armstrong CL, Leidy HJ, et al. Normal vs. high-protein weight loss diets in men: effects on body composition and indices of metabolic syndrome. Obesity. 2013 Mar; 21 (3): E204-10.
- Abete I, Parra D, De Morentin BM, et al. Effects of two energy-restricted diets differing in the carbohydrate/protein ratio on weight loss and oxidative changes of obese men. Int J Food Sci Nutr. 2009; 60 Suppl 3:1-13.
- Wycherley TP, Moran LJ, Clifton PM, et al. Effects of energy-restricted high-protein, low-fat compared with standard-protein, low-fat diets: a meta-analysis of randomized controlled trials. Am J Clin Nutr. 2012 Dec; 96(6):1281-98
- Johnston CS1, Day CS, Swan PD. Postprandial thermogenesis is increased 100% on a high-protein, low-fat diet versus a high-carbohydrate, low-fat diet in healthy, young women. J Am Coll Nutr. 2002 Feb; 21(1):55-61
- Leidy HJ, Armstrong CL, Tang M, et al. The influence of higher protein intake and greater eating frequency on appetite control in overweight and obese men. Obesity (Silver Spring). 2010 Sep;18(9):1725-32.
- Gannon MC1, Nuttall FQ. Effect of a high-protein diet on ghrelin, growth hormone, and insulin-like growth factor-I and binding proteins 1 and 3 in subjects with type 2 diabetes mellitus. Metabolism. 2011 Sep;60(9):1300-11