Updated U.S. Dietary Guidelines Raise Protein Recommendations to 1.2–1.6 g/kg/Day, but Experts Question Universal Application
核心洞察
The 2025-2030 Dietary Guidelines for Americans now recommend 1.2–1.6 g/kg/day of protein, up from the long-standing 0.8 g/kg/day, particularly for weight management in overweight (搜索) and obesity (搜索).
A new Perspective in The Journal of Nutrition acknowledges the guideline's strengths but argues evidence is insufficient to justify a universal higher-protein recommendation for all Americans across the lifespan.
Experts note that protein needs vary by age, activity level, health status, and goals, with groups such as those over 40, on GLP-1 (搜索) medications, or with cardiometabolic diseases (搜索) potentially benefiting most.
The 2025-2030 Dietary Guidelines for Americans have introduced an updated protein intake recommendation of 1.2 to 1.6 grams per kilogram of body weight per day—a notable increase from the long-standing recommended dietary allowance (RDA) of 0.8 g/kg/day. However, a new Perspective published in The Journal of Nutrition questions whether the evidence base is robust enough to support applying this higher range universally across the entire U.S. population.
The current RDA of 0.8 g/kg/day, as Michelle Routhenstein, MS, RD, pointed out, was established to prevent protein deficiency and "not necessarily to optimize muscle health, healthy aging, or cardiometabolic resilience." The updated range in the new Dietary Guidelines reflects a growing body of research linking higher protein intakes to benefits including weight management, lean muscle preservation, and metabolic health.
Strengths and Limitations of the New Guidance
The Perspective, authored by Dr. Stefan Pasiakos, Professor at Pennington Biomedical Research Center, and colleagues, acknowledges the strengths of the 2025-2030 Dietary Guidelines. These include a continued focus on healthy, nutrient-dense eating patterns and the evidence supporting protein intakes of 1.2 to 1.6 g/kg/day for weight management in individuals with overweight (搜索) and obesity (搜索).
Speaking on behalf of his co-authors, Dr. Pasiakos stated: "We acknowledge the strengths of the 2025-2030 Dietary Guidelines for Americans, particularly the emphasis on high-quality protein foods and the evidence supporting higher protein intakes for weight management, but the central purpose of our Perspective was to examine whether this evidence is sufficient to justify a universal higher-protein dietary recommendation for all Americans across the lifespan."
He added: "The guidelines fall short of that standard, and what is optimal for one segment of the population should not be considered optimal for all without sufficient evidence. We hope future editions of the Dietary Guidelines are grounded in an evidence base broad enough to serve all Americans, not only those for whom the current data were generated."
Personalization Over One-Size-Fits-All
Kristin Kirkpatrick, a registered dietitian, emphasized that although the current guidelines provide a good starting point, they do not offer a personalized approach to maximize health and longevity. "Protein needs vary based on factors like age, activity level, health status, and even goals," she said.
Routhenstein noted that certain groups may particularly benefit from higher protein intake, including people older than age 40, those taking GLP-1 (搜索) medications, individuals trying to lose weight, and those with cardiometabolic diseases (搜索) such as obesity (搜索).
Kirkpatrick illustrated this variability with examples from her own practice: "Right now, I'm doing this with a 14-year-old athlete, a menopausal woman taking a GLP-1 (搜索) medication, and an older man struggling to get enough calories. Three very different people, with three very different protein recommendations. That's why I don't believe a one-size-fits-all recommendation works for everyone."
Practical Implementation and Dietary Balance
Routhenstein explained that a range of about 1.2–1.6 g/kg per day is "often more supportive of preserving lean muscle, maintaining metabolic health, improving satiety, and supporting physical function." She emphasized that protein works best as part of an overall heart-healthy dietary pattern.
Achieving this target through whole foods is feasible, according to Routhenstein. For those on a vegan diet, adequate sources include tofu, tempeh, beans, and legumes. For those who consume animal protein, a combination of animal and plant-based sources evenly split between meals can be effective.
Kirkpatrick recommended spreading protein intake throughout the day: "Think eggs or Greek yogurt at breakfast, lean protein like chicken, fish, beans, or lentils at both lunch and dinner, and protein-rich snacks throughout the day."
Both experts cautioned against focusing on protein to the exclusion of other nutrients. "If you only focus on protein intake, it can definitely crowd out other nutrients like vitamin C, potassium, magnesium, folate, and fiber, which are important for optimal heart and overall functional aging," Routhenstein warned. Kirkpatrick added: "Eating more protein shouldn't mean eating less fiber, fruits, vegetables, or healthy fats."
The Path Forward
The authors of the Perspective emphasize the essentiality of protein in the diet and encourage further research to better understand protein needs across populations. Key areas for future investigation include how protein recommendations may need to differ across life stages and populations, and the role of protein in preventing and managing chronic disease.
These topics will be further discussed at NUTRITION 2026, the American Society for Nutrition (搜索)'s flagship annual meeting, scheduled for July 25–28, 2026, in National Harbor, MD, where sessions on protein metabolism, dietary patterns, muscle health, and healthy aging will feature prominently.