Quick Takes

Will protein hurt your kidneys? Not if they're healthy. And even if you have early kidney disease, low protein carries its own risk — you lose muscle, become frail, and frailty kills. Don't accept a protein restriction without asking what your muscle mass and strength actually are.

Will protein hurt your bones? Only if your calcium is inadequate — and most people's is. The target is 1,000–1,200 mg/day. If you don't eat dairy, your realistic options are fortified plant milk, calcium-set tofu, or supplements. Most plant calcium is poorly absorbed. Don't assume. Check.

Know your muscle quality. Protein targets depend on what you're starting with. A simple grip strength test or 30-second sit-to-stand tells you something a blood test or even a DEXA body composition scan may not.

Protein without strength training may not do the job. Protein gives muscles the raw material. Resistance exercise gives them the reason to use it. Without strength training, higher protein has a fraction of the effect. The evidence for benefit from resistance exercise continues into your 80s and beyond. It belongs in every protein conversation.

How much protein? More than you think, and spread through the day. The old recommendation of 0.8 g/kg was designed to prevent deficiency, not to keep you strong. Aim for 1.2-1.6 g/kg — and at least 25–30 grams at each meal, not just dinner.

Favorite Finds

What is special about the article that inspired today’s post is that it brought together in spectacular function all the best researchers in the field of protein studies. This type of collaborative article is very difficult to pull off!! So, this newsletter is presented with our congratulations to Kanter MM, Aaron S, Austad SN, Brown AW, et al. Examining widely held propositions on human dietary protein needs and benefits: a critical review of the science that shapes both the data and our understanding of an essential macronutrient. Crit Rev Food Sci Nutr. 2026;64(6):ePub ahead of print.

SUMMARY OF THE ARTICLE:
RDA vs optimal: The 0.8 g/kg/day benchmark was designed to prevent deficiency in ~97% of healthy adults, not to optimize function, muscle mass, or resilience. Many individuals — especially those over 65 or under metabolic stress — likely benefit from higher intakes.

Aging and sarcopenia: Intakes of 1.2–1.6 g/kg/day, combined with resistance training, consistently support lean mass and functional outcomes in older adults. Benefits plateau at high doses; distribution across meals and per-meal adequacy matter as much as daily totals.

Weight management: Higher protein improves satiety and preserves lean mass during caloric restriction — but does not override energy balance. Long-term weight outcomes still depend primarily on total calories and adherence.

Protein quality: Animal proteins have higher indispensable amino acid content and per-gram anabolic effect. Well-planned plant-based diets can meet needs when total intake is sufficient and varied. Overall dietary pattern matters more than source rankings in mixed diets.

Bone: The "high protein leaches calcium and harms bone" claim is not supported when calcium intake is adequate. Contemporary data are neutral to modestly positive for bone mineral density and fracture risk with higher protein intakes.

Kidney: Higher protein raises GFR and renal workload but does not cause CKD in healthy individuals. In established CKD, higher intake may accelerate decline — individualization is essential. The evidence does not support blanket restriction.

Takeaway: Individualize protein targets by age, health status, and goals. Neither "RDA is sufficient for everyone" nor "more is always better" reflects the evidence. Context — especially frailty, comorbidity, dietary pattern, and calcium adequacy — determines the right answer for each patient.

Deep Dive

How can you make a decision about protein intake in your specific situation? Details are here. Free, no paywall 😊