Protein for Muscle Growth and Healthy Aging: How Much Do You Need?

Protein supplies amino acids that your body uses to maintain and repair muscle. But more is not always better, and the useful amount depends on your age, training, total energy intake and health status.

For muscle and healthy aging, protein works best alongside resistance training. In 2026, the American College of Sports Medicine updated its resistance-training guidance after reviewing 137 systematic reviews involving more than 30,000 participants. The central message is simple: consistent resistance training drives strength and muscle gains; nutrition supports that adaptation.

How much protein do you need?

There is no single number for everyone. The ranges below are practical evidence-informed starting points for generally healthy adults, not prescriptions for people with kidney disease or other conditions requiring individualized nutrition.

For someone weighing 70 kg, 1.0–1.2 g/kg/day is about 70–84 g of protein, while 1.6 g/kg/day is about 112 g.

Do you need 2 grams per kilogram?

Not routinely. Higher protein intakes are sometimes used by athletes, people dieting aggressively or people with specific clinical needs, but that does not mean everyone gains more muscle by pushing protein higher.

In a major meta-analysis of resistance-training studies, gains in fat-free mass appeared to plateau at roughly 1.62 g/kg/day. This does not make 1.6 a magic number; it is better viewed as a practical ceiling for the average additional muscle-building benefit seen in that research.

Older adults: why protein becomes more important

Aging is associated with progressive loss of muscle mass and function and with a reduced anabolic response to food and exercise in some circumstances. Maintaining strength becomes increasingly important for mobility, balance and independence.

A 2026 Singapore review on sarcopenia cites protein targets of approximately 1.0–1.2 g/kg/day for healthy older adults, with higher individualized intakes used in illness, frailty or malnutrition. It also emphasizes that protein supplementation is most useful when paired with resistance exercise rather than treated as a stand-alone solution.

For training guidance, start with our Strength Training & Weight Lifting hub or the Beginner Weight Training Program.

How much protein per meal?

Total daily protein matters most, but spreading protein across meals can make it easier to reach your target and may be especially useful for older adults.

A practical older-adult heuristic is roughly 25–30 g of protein per meal, or around 0.4 g/kg per meal. This is not a strict biological limit. Your body can digest and use more than 30 g of protein; the figure is simply a practical amount that has been studied for stimulating muscle protein synthesis.

Seven useful high-protein foods

You do not need a “superfood.” A varied diet can provide protein from both animal and plant sources.

Can plant protein build muscle?

Yes. Plant-based diets can provide sufficient protein for muscle maintenance and growth when total intake, food variety and overall energy intake are adequate. Soy foods, legumes, grains, nuts and seeds can contribute meaningfully.

Some plant proteins contain less of one or more essential amino acids per serving than many animal proteins, but you do not need to combine “complementary proteins” at every single meal. Eating a varied diet across the day is generally sufficient.

Do you need protein powder?

No. Protein powder is a convenience product, not a requirement for muscle growth. Whole foods can meet protein targets while also providing vitamins, minerals, fiber and other nutrients.

A supplement can be useful when appetite is low, meals are rushed, dietary restrictions make intake difficult, or a higher target is otherwise hard to reach. If you use one, treat it as food supplementation rather than as a muscle-building shortcut.

When should you eat protein?

The idea that you must consume protein within a tiny “30-minute anabolic window” is overstated. A protein-containing meal within a reasonable period around training is practical, but your total daily protein and consistent resistance training are more important than minute-by-minute timing.

For many people, simply including a substantial protein source at breakfast, lunch and dinner is a better strategy than eating very little protein all day and most of it at one evening meal.

Protein while losing weight

During an energy deficit, adequate protein plus resistance training can help preserve lean mass. This matters because weight loss can include both fat and lean tissue. Protein cannot prevent every loss of lean mass, but it is one component of a better-designed weight-management plan.

What if you have kidney disease?

Do not automatically apply high-protein muscle-building targets if you have chronic kidney disease. Protein requirements change with kidney function and whether someone is receiving dialysis. NIDDK advises people with CKD to work with a healthcare professional or renal dietitian to determine the appropriate amount; some people who are not on dialysis need a more moderate protein intake, while dialysis can increase protein needs.

A simple practical template

• Include a meaningful protein source at each main meal.
• Use resistance training consistently; protein does not replace training.
• Choose a mixture of plant and/or animal protein sources that fits your preferences.
• For healthy older adults, pay particular attention to breakfast and lunch, where protein intake is often low.
• Use protein powder only when it genuinely makes the diet easier.
• Do not chase very high intakes if you are already meeting an effective target.

Explore the broader Nutrition & Healthy Eating hub for dietary-pattern guidance.

Bottom line

For healthy adults who resistance train, around 1.6 g/kg/day is a useful evidence-based target and going substantially higher does not consistently produce more lean-mass gain. For healthy older adults, approximately 1.0–1.2 g/kg/day is commonly recommended, with active older adults often benefiting from at least about 1.2 g/kg/day. The strongest combination for preserving or building muscle remains adequate protein plus progressive resistance training.

Sources

• American College of Sports Medicine: 2026 Resistance Training Guidelines
• Morton et al.: protein supplementation and resistance training meta-analysis
• Annals, Academy of Medicine Singapore: Sarcopenia—current evidence and clinical implementation
• Protein and Aging: Practicalities and Practice
• NIDDK: Healthy Eating for Adults with Chronic Kidney Disease

Medical note: Protein needs can change with kidney disease, liver disease, pregnancy, frailty, acute illness, malnutrition and other medical conditions. Individualized clinical advice takes priority over general targets.