Can high protein damage healthy kidneys?

No, in adults without kidney disease. Multiple long-term studies including the Nurses' Health Study found no association between high protein intake (over 2 g/kg/day) and kidney function decline in adults with normal eGFR. The recommendation to limit protein for kidney protection applies to existing chronic kidney disease, not to healthy kidneys.

Is 30 grams the maximum protein per meal?

No, but the marginal return on muscle protein synthesis tapers above about 0.4 to 0.6 g/kg per meal (roughly 30 to 50 g for most adults). A single 60 g meal does not build proportionally more muscle than a 30 g meal. Above the threshold, the extra protein is oxidized for energy or used for other functions. For maximum muscle gain, distribute total protein across 3 to 5 meals.

Do I need protein right after training?

Not within 30 minutes. The original anabolic window research overestimated how narrow the window is. Updated meta-analyses suggest the post-workout window is closer to 4 to 6 hours, and total daily protein matters more than timing. Get a normal meal within a few hours of training and you are fine.

Should older adults eat more protein?

Yes. Anabolic resistance (the reduced muscle protein synthesis response to a given dose of protein) starts around age 50 and grows steadily with age. Per-meal protein threshold rises from about 0.4 g/kg to 0.6 g/kg by age 70. Sarcopenia prevention guidelines now recommend 1.2 to 1.6 g/kg/day for adults over 65, with meals of 30 to 40 g of high-leucine protein.

How much protein you actually need

Jillian Foglesong Stabile, MD

FAAFP, DABOM · Reviewed June 10, 2026 · ISSN 2017 bands

Body weight

Goal

Screening estimate only, not a medical or nutrition prescription. Protein needs vary with activity, age, health conditions, and kidney function, so a licensed physician or dietitian personalizes targets. Individual results vary.

Chapter 01 · The floor

Why the RDA is too low for most people

The 0.8 g/kg RDA was set in 1980 for sedentary adults. It is designed to prevent deficiency, not to optimize body composition or recovery. Active people, older adults, recovering patients, and people on calorie deficits all need more than the RDA to maintain lean mass and support training.¹

Goal	Protein band	What it supports
General health (RDA)	0.8 g/kg	Prevents deficiency in sedentary adults
Endurance athlete	1.2 to 1.4 g/kg	Supports repeated training loads
Active adult	1.2 to 1.6 g/kg	Maintains lean mass with activity
Muscle gain	1.6 to 2.2 g/kg	Supports building new muscle
Weight loss, preserve muscle	1.6 to 2.4 g/kg	Holds onto lean mass in a deficit

Weight loss demands the most protein, to hold onto lean mass in a deficit.

Chapter 02 · The timing

Per-meal distribution

Muscle protein synthesis is triggered above a leucine threshold, roughly 0.4 g/kg per meal in adults. Three meals of 30 g beat one meal of 90 g for building muscle, because the body can only use so much per sitting before the rest is oxidized for energy.² Spreading total protein across 3 to 5 meals is the practical takeaway.

Total daily protein matters most, but distributing it across meals gets you more from the same total. Individual results vary.

Chapter 03 · The caveat

The kidney question

Healthy kidneys handle 2.0 g/kg and above without issue; long-term studies in adults with normal kidney function find no association between high protein intake and decline in kidney function. The recommendation to limit protein applies to existing chronic kidney disease or hepatic disease, which requires physician supervision before increasing protein. Individual results vary.³

Every medication on sipra is prescribed by a licensed physician, so your care always starts with a visit. Your sipra membership gives you ongoing access to those physician visits, so you can check in, adjust your plan, and ask questions whenever you need, without paying per visit. It is how we keep high-quality care convenient: one membership, physician access whenever you need it, and support at every step.

Sources

Jäger R et al. "International Society of Sports Nutrition Position Stand: protein and exercise." Journal of the International Society of Sports Nutrition. 2017;14:20. doi.org
Morton RW et al. "A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength." British Journal of Sports Medicine. 2018;52(6):376-384. doi.org
Helms ER et al. "A systematic review of dietary protein during caloric restriction in resistance trained lean athletes." Journal of the International Society of Sports Nutrition. 2014;11:20. doi.org

Compounded medications are not FDA-approved and require a patient-specific prescription. Brand names are trademarks of their owners; sipra is not affiliated with them.

General education, not medical advice. Last reviewed June 10, 2026 by Jillian Foglesong Stabile, MD, FAAFP, DABOM. Prices snapshot ISSN 2017 bands. Individual results vary.