As much as it is emphasized and discussed, we realize that many of you still have questions about protein. Questions about protein digestion, quantity, and quality, as well as ways to optimize protein intake, are all very common and are important for you to understand in relation to your long-term nutritional status. My role as a member of the Bariatric Eating team is to address those questions and support each of you in achieving your nutritional goals every day. - Dr. Myers
Protein, the Thermic Effect and Weight Management
What if I told you that eating the right kind of foods can increase your metabolism for a few hours?
It just so happens that the extra calories required to digest, absorb and process the nutrients in a meal create something called the thermic effect of food (TEF). Thermic means “relating to heat” and the TEF represents about 10% of the caloric intake of healthy adults eating a standard mixed diet. Your personal TEF will depend on your lean body mass (amount of muscle) and the composition of your meal – meaning the ratio of protein to fat to carbohydrates.
The energy required to digest each macronutrient (macro TEF) can be expressed as a percentage of the energy provided by this nutrient:
- Fat provides 9 food calories per gram, and its TEF is 0–3%.
- Carbohydrate provides 4 food calories per gram, and its TEF is 5–10%.
- Protein provides 4 food calories per gram, and its TEF is 20–30%.
From a thermic perspective, protein provides nearly 10x the effect of dietary fat.
Protein at around 25–30% of total daily calories has been shown to boost metabolism by up to 80–100 calories burned per day, compared to lower protein diets.
The TEF of protein is one reason why your daily protein intake is important when it comes to losing weight and maintaining weight loss.
An increased protein intake is one of the best ways to preserve (and even increase) your muscle mass. Muscle is the factory in our body which burns fat and promoting protein promotes your lean muscle. In upcoming articles, we’ll cover the relationship amongst protein, exercise and lean muscle mass from a weight loss perspective.
A study from the International Journal of Obesity found that modestly increasing protein intake from 15% to 18% of daily calories reduced the amount of fat that participants regained after weight loss by 50%.
This study underscores the importance of maintaining an intake of around 75 to 90 grams of protein a day.
Pesta DH, Samuel VT. A high-protein diet for reducing body fat: mechanisms and possible caveats. Nutr Metab (Lond). 2014;11(1):53. Published 2014 Nov 19.
Westerterp-Plantenga MS, Lejeune MP, Nijs I, van Ooijen M, Kovacs EM. High protein intake sustains weight maintenance after body weight loss in humans. Int J Obes Relat Metab Disord. 2004;28(1):57-64.