A recent study published in the journalCritical Reviews in Food Science and Nutritionquestions the common belief that consuming more and more protein is the best strategy for those looking to lose weight in a healthy way. Instead, the researchers highlight that maintaining an adequate intake of the nutrient, adjusted for body weight, may be more effective in preserving muscle mass during a calorie deficit.
The research, which synthesizes discussions from a workshop held in February 2025 at the Indiana University School of Public Health, in Bloomington (USA), brought together more than 20 international experts. They evaluated 11 widely accepted propositions about the needs and benefits of dietary protein.
Many of these ideas did not have enough robust scientific evidence for full acceptance, although several were considered plausible based on preliminary data. The main focus was on aspects such as muscle protein synthesis, repair, growth and, especially, the needs during weight loss.
Quality of evidence in question
The experts analyzed methodological issues that affect data interpretation, as well as acute protein intake thresholds and possible negative effects of excessive amounts. The result points to the need for more high-quality research on several fronts.
During weight loss, the practical recommendation that is gaining strength is to prioritize maintaining the usual levels of protein per kilogram of body weight, instead of simply increasing the absolute consumption in grams. This approach helps protect lean mass, which is essential for keeping your metabolism active in the long term.
Why Muscle Preservation Matters
Losing muscle along with fat during a diet reduces basal energy expenditure and can make it difficult to maintain the weight lost. Previous studies have already indicated that intakes above the traditional RDA (0.8 g/kg/day) help with muscle retention, especially when combined with strength training. The new work reinforces that balance and consistency are more decisive than exaggeration.
For the general population, values between 1.2 g and 1.6 g per kilogram of body weight appear as the most appropriate reference in contexts of weight loss and aging, depending on the level of physical activity. Various sources, of animal or vegetable origin, can contribute, as long as the quality and distribution throughout the day are observed.
Practical implications for those who lose weight
Those who are in the process of losing weight do not necessarily need to double their portion of chicken breast or whey shakes. The most important thing is to ensure that protein does not fall below the body’s usual level, maintaining balanced meals and prioritizing resistance exercise.
This nuance brings relief to those who fear that restrictive diets always compromise their muscles. At the same time, it reinforces the importance of professional guidance, as needs vary depending on age, body composition and individual goals.