A Dietitian Says This Is the Best Protein for Aging Muscles

 I add this to my KA'chava drink but it doesn't dissolve very well. Probably not getting enough.

A Dietitian Says This Is the Best Protein for Aging Muscles

Muscle loss is hard to avoid as you age, but eating enough high-quality protein can help you stay strong, mobile, and independent.

As we age, our strength and muscle mass inevitably decline — by approximately three percent and one percent per year, respectively, according to one review published in 2019. You may think muscle is mainly for gym bros chasing bigger pecs, but muscle tissue does far more than fill out a T-shirt. It moves and supports your joints, helps keep you steady and able-bodied, and may even be a relatively strong predictor of longevity.

In other words, holding on to your muscle as you age should be a priority. Doing that requires regular strength training and enough protein. That’s the macronutrient your body uses to build and repair muscle, along with your cells, hair, nails, and other tissues. But not all protein sources affect muscle in exactly the same way. Complete proteins provide all nine essential amino acids, including the ones most directly involved in stimulating muscle growth. And according to one dietitian, a familiar supplement may be especially useful for maintaining muscle as you age.

What You Should Know About Protein and Aging Muscle

Registered dietitian Jillian Kubala points to whey protein as one of the best options for maintaining muscle with age. Whey is a complete protein, meaning it contains all nine essential amino acids. Those are the building blocks of protein that your body cannot produce on its own. It also delivers a substantial amount of protein for relatively few calories and is easy to mix into a shake, smoothie, or meal.

That combination of nutritional value and convenience can make whey especially useful for older adults who have a smaller appetite or little desire to prepare protein-heavy meals from scratch. Protein provides the raw material your body needs to repair and build muscle, while strength training gives it a reason to do so.

Muscle loss with age is not caused by one factor alone. People often eat less protein and become less active over time, while age-related changes also make the body somewhat less responsive to both protein and exercise. Eating enough high-quality protein and continuing to resistance train can help counter those effects at nearly any age.

Going Deeper: Why Whey, and How Much You Need

Amino acids are organic molecules that create the protein your body needs to build muscle, sure, but also perform hundreds of other bodily processes. Your body needs 20 amino acids to function, and of those 20, nine are considered “essential,” meaning your body needs them but can’t create them on its own. You can obtain these amino acids only from food or supplements.

Almost any whey protein supplement you purchase will contain all nine essential amino acids. Whey is also particularly rich in the three branched-chain amino acids, or BCAAs: leucine, isoleucine, and valine. The body burns through BCAAs right in the muscle, and their distinctive branched structure makes them especially important for building new muscle and repairing it after a workout.

Whey’s amino acid profile isn’t its only advantage. It’s also digested relatively quickly, meaning those amino acids enter your bloodstream and become available to your muscles faster than they would with many other protein sources. Leucine is especially important here because it helps flip the switch on muscle protein synthesis — the process your body uses to repair and build new muscle tissue. Research supports this.

• A 2020 review found that whey protein may promote muscle protein synthesis, improve muscle performance, protect against age-related muscle loss, and even reduce fall risk in adults over 65. 
• A 2024 review found that combining whey protein with resistance training improved muscle mass and strength in older adults with sarcopenia. 
• And a 2026 review found that pairing whey with resistance training produced some of the most meaningful improvements in muscle and strength. 

As for how much protein you need, the old recommended daily allowance (RDA) of 0.8 grams per kilogram (about 0.36 per pound) is really just the floor to prevent deficiency — most adults benefit from more. The 2025-2030 Dietary Guidelines for Americans now put the healthy range at 1.2 to 1.6 grams per kilogram (0.54 to 0.73 per pound); for a 150-pound person, that’s about 81 to 110 grams a day, and anyone trying to hold onto muscle or living an active life should aim toward the top of that range.

Older adults have specific targets. Experts recommend at least 1.0 to 1.2 grams per kilogram (about 0.45 to 0.54 grams per pound) — well above the RDA — just to preserve muscle. Those actively building, recovering from illness, or at risk of malnutrition may need 1.5 to 2 grams per kilogram (about 0.68 to 0.91 per pound) — about 102 to 136 grams a day for that same 150-pound person.

The Takeaway

Whey protein is a convenient, easy-to-absorb supplement that can help older adults reach higher protein targets, especially when appetite or meal preparation becomes a barrier. But the supplement works best when it’s paired with resistance training. Protein provides the raw materials, and the workout puts them to use to build muscle mass. Whole-food and plant proteins still count, too; whey is simply one convenient option.

Bottom Line

Whey is a complete, leucine-rich, and research-backed supplement for helping older adults preserve muscle, particularly when combined with strength training. Still, it’s not magic, and it’s not the only quality protein that works. Total daily protein intake and consistent resistance training are the real drivers of muscle retention, which matters for staying strong, mobile, balanced, and independent as you age.

Experts Who Contributed

• Andrew Gutman, NASM-CPT, wrote this article.
• Lauren Keary, NASM-CNC, reviewed this article for accuracy.

Seven mistakes a personal trainer says seniors should stop making at the gym

 You competent? doctor and therapist taught you all this already at the hospital gym, right? Sarcasm tag needed here!

Seven mistakes a personal trainer says seniors should stop making at the gym

Strength training is not solely the domain of bodybuilders; it is a crucial component of health and independence for everyone, particularly as we age.

When executed correctly, it plays a pivotal role in preserving bone density and building muscle mass, significantly enhancing overall quality of life.

However, the prospect of entering a gym can be daunting, and improper use of equipment poses risks, making safety paramount.

For seniors embarking on a strength training journey, understanding common pitfalls is essential to ensure a safe and effective start.

Here are seven common mistakes to watch out for when starting strength training as a senior.

1. Starting too heavy

“Our muscles, bones and connective tissues take time to adapt to resistance training, so if you start with weights that are too heavy, it creates unnecessary injury risk. It can also encourage poor movement patterns that are much harder to correct later,” explains Michael Betts, personal trainer and director of TRAINFITNESS.

Betts advises seniors looking to embark on their strength training journey to start off with body weight exercises or very light weights that almost feel too easy.

“Aim for 12-15 reps with perfect form before starting to think about increasing the weight,” recommends the personal trainer. “Approaching it like this builds strength progressively while at the same time teaching your nervous system the proper movement patterns to complete the exercises safely.”

2. Prioritising repetitions over technique

Sloppy technique doesn’t just stall progress; it increases injury risk.

“Prioritise slow, controlled movements over the amount of resistance or number of repetitions,” advises Leo Mathew, physiotherapist and rehabilitation service lead at Nellsar Care Homes. “Good technique helps prevent injuries and supports gradual progress.”

This is why seeking professional advice when starting out can be extremely beneficial.

“Invest in a few sessions with a qualified trainer who has experience working with older adults,” recommends Betts.

“They can assess your movement quality, design an appropriate programme and teach you proper form. This upfront investment prevents costly mistakes and gives you the confidence to train independently.”

3. Forgetting about a mobility warm-up

“If you’re strong but don’t have mobility, your movement patterns will be generally imbalanced and your exercise options will be limited,” says Betts.

“A lot of seniors jump straight into lifting before addressing issues like tight hips, rounded shoulders or limited mobility in their ankles which have developed from years of sitting.”

Betts recommends spending 10-15 minutes before a weights session working on dynamic stretches and mobility exercises to make your weight session more effective and reduce your risk of injury.

“The focus should be on your hips, shoulders and thoracic spine – the last of which is very commonly neglected,” says the personal trainer. “Preparing in this way prevents compensatory movements which are more likely to lead to injury and also ensures that the exercises are working the muscles they should be.”

4. Ignoring pain

Many people think pain is normal when it comes to strength training, but it’s important to listen to your body.

“Stop immediately if experiencing new pain, dizziness, or sharp discomfort – never force through these symptoms. Take advice if required.”

5. Neglecting balance and stability

“Traditional strength training often uses machines and supported positions that aren’t challenging for our balance systems,” notes Betts. “Balance is a fundamental part of functional strength that helps prevent falls and improves the quality of day-to-day movement – things that are incredibly important as we age.

“Include single-leg exercises, standing exercises and movements that challenge your stability. Simple progressions like standing on one foot, single-leg dead lifts or standing exercises with eyes closed help maintain the balance systems that naturally decline with age.”

6. Not allowing time for rest and recovery

Rest days from the gym are not lazy, they are crucial for your body’s recovery and for any long-term progress.

“Allow adequate rest during your exercise to improve strength, endurance and recovery,” advises Mathew. “Allow 2-3 rest days per week for muscle repair. Stay well-hydrated and eat nutritious foods to support and fuel recovery, performance and to maintain quality of life.”

7. Not eating enough protein

“Sufficient caloric and protein intake is required to build muscle and strength and repair from workouts and physical stress on the body,” explains Sam Quinn, personal training lead at Nuffield Health.

“We naturally maintain less muscle mass as we get older, and consuming the correct amount of protein to support our physical health and exercise goals is even more important. Between 1.1-2g of protein per kilogram of body weight is recommended to build strength and recover from your workouts.”

Good sources of protein include lean meats, poultry, fish, eggs, dairy products, beans, lentils, tofu, nuts and seeds.

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Eating too much protein could backfire, experts warn after longevity review

 Simple. Have your competent? doctor give you EXACT PROTEIN PROTOCOLS! Can't do that; PURE INCOMPETENCE! I expect competence from medical staff and have been sorely disappointed!

Eating too much protein could backfire, experts warn after longevity review

A recent scientific review challenged the idea that consuming more protein necessarily leads to better health, suggesting that the optimal amount depends on factors such as age, activity level and overall health.

After reviewing more than 350 studies, researchers at the University of Wisconsin-Madison concluded that while higher protein intake can support muscle growth and other health benefits, consuming more than the body needs may offer little advantage.

In fact, it could even reduce longevity in some sedentary adults,(Sounds like us stroke survivors.) particularly when protein comes from certain sources or amino acid profiles, they concluded.

For those wondering how to adjust their own diets in light of these findings, the answer lies in personalization(Like an EXACT DIET PROTOCOL  from your competent? doctor!), activity level and food sources, according to experts.

"We are hearing conflicting things from doctors ... and influencers," Tanya Freirich, a registered dietitian nutritionist in Charlotte, North Carolina, told Fox News Digital.

READ ON THE FOX NEWS APP

"The message lately has been to increase your protein," said the expert, who was not involved in the research. 

"However, we do know that excess protein is associated with negative effects. It can put a strain on your kidney health, and it can interfere with bone and calcium homeostasis."

For sedentary individuals, cutting back on excess protein isn’t the only option, according to Freirich. Increasing physical activity can also help the body use nutrients more effectively.

"If you are moving your body — strength training, building muscle or doing sports — you probably do need a little bit more protein," she noted.

"Now, let's say you were a super active person and unfortunately had an injury and have gone down to a very sedentary level — you should modify your protein because your body is not utilizing it in the same way."

Exercise may also support longevity in ways that go beyond nutrition, Freirich noted, by helping people stay active and independent.

"Adding exercise is always a good idea because it is associated with having fewer falls, having more joy in life and protecting you from injury," she said.

For those looking to rebalance their nutrition without doing a total overhaul, Freirich offered the following five tips.

No. 1: Focus on plate proportions: Aim for 50% of your plate to consist of vegetables, 25% protein and 25% starches or whole grains.

No. 2: Do the quick math: A general guideline is to consume 0.8 grams of protein per kilogram of body weight per day for adults with lower activity levels, while those who are more physically active may benefit from about 1.0 gram per kilogram per day.

No. 3: Eat the rainbow: Incorporate fruits and vegetables across various colors to ensure a diverse intake of vitamins and micro-nutrients.

No. 4: Switch to plant proteins: Shift a portion of animal protein toward plant-based alternatives like lentils, beans, chickpeas and seeds. "A lot of people who were on protein-restricted diets and saw better health outcomes were eating a lot of their proteins from plants," Freirich noted.

No. 5: Stick to whole foods: Unprocessed foods support natural satiety signals. "Moving away from really processed foods to more unprocessed foods actually helps your body regulate a lot better," Freirich advised.

Ultimately, dietary choices shouldn't be governed by a single headline or study, according to the expert.

CLICK HERE TO DOWNLOAD THE FOX NEWS APP

"Research is ever-evolving," Freirich said. "Everyone should think about their personal situation and discuss it with healthcare providers to figure out the best route for them."

Original article source: Eating too much protein could backfire, experts warn after longevity review

Are Low-Protein Diets Better For Aging? What A New Study Actually Shows by mindbodygreen

 What to do? I wouldn't bother asking your doctor.

Are Low-Protein Diets Better For Aging? What A New Study Actually Shows

New studies highlight evolving insights on diet, exercise, and prevention

 Have your competent? doctor DETERMINE THE EXACT AMOUNT OF PROTEIN YOU NEED! EXACT!

New studies highlight evolving insights on diet, exercise, and prevention

1. New studies highlight evolving insights on diet, exercise, and prevention

Protein moderation: A large review links lower protein intake to better metabolic function and longevity, though adequate protein remains important for muscle and health.

Dietary patterns matter: A Canadian analysis shows vegetable-rich diets correlate with longer life expectancy, while high processed food intake shortens it.

Movement benefits heart: Long-term studies find lifestyle changes in prediabetes and regular activity in AFib patients reduce multiple chronic diseases and death risk.

References

A surprising new study makes the case for a low-protein diet | Prevention
Study finds healthy eating patterns matter more than individual foods | Mens Fitness
AFib patients who exercise live up to 1.2 years longer, 87,000-person study shows | Tech Times
A long-term prediabetes intervention lowered the risk of multiple chronic diseases | Morning Overview
Biweekly GLP-1 drug clears first human test via dual fatty acid engineering | Tech Times
Latest Self Improvement Trends 2026 Explained - accio.com | accio.com
[SPONSORED] Top Self-Improvement Apps for Students in 2026 Guide | The Daily Princetonian

2. Canadian Machine Learning Study Connects Vegetable-Rich Diets to Lower Mortality

A Canadian study employing machine learning techniques found that long-term eating patterns rich in vegetables were associated with reduced mortality and increased life expectancy. The research highlights the potential long-term benefits of plant-heavy diets.

References

A surprising new study makes the case for a low-protein diet | Prevention
Study finds healthy eating patterns matter more than individual foods | Mens Fitness

3. Dietitians emphasize protein's role in muscle mass and health

Dietitians state that while reducing protein intake may benefit some individuals, protein remains essential for preserving muscle mass and supporting overall health. They caution against eliminating or drastically reducing protein without considering its critical functions in the body.

References

A surprising new study makes the case for a low-protein diet | Prevention
Study finds healthy eating patterns matter more than individual foods | Mens Fitness

4. Long-term lifestyle intervention for prediabetes

A structured lifestyle intervention was implemented for individuals with prediabetes over an extended period. The program aimed to address prediabetes through sustained changes in diet, physical activity, and other health behaviors. Participants received ongoing support to maintain these lifestyle modifications.

References

A surprising new study makes the case for a low-protein diet | Prevention
A long-term prediabetes intervention lowered the risk of multiple chronic diseases | Morning Overview
Study finds healthy eating patterns matter more than individual foods | Mens Fitness

5. Analysis of 87,000 Adults Finds Low-Level Activity Reduces Stroke and Death Risk in Atrial Fibrillation

So make sure your competent? doctor gets your recovered enough for this amount of exercise to prevent your next stroke!

An analysis involving more than 87,000 adults revealed that even low amounts of regular physical activity were linked to reduced risks of stroke and death among people with atrial fibrillation. The study suggests that modest exercise can yield significant cardiovascular benefits in this population.

References

A surprising new study makes the case for a low-protein diet | Prevention
AFib patients who exercise live up to 1.2 years longer, 87,000-person study shows | Tech Times
Study finds healthy eating patterns matter more than individual foods | Mens Fitness

6. Cardiologists link extreme endurance training to increased AFib risk

Another reason not to do high intensity training.

Cardiologists note that while even light physical activity benefits patients with atrial fibrillation, extremely intense endurance training may increase health risks for some individuals. They advise moderation in exercise intensity for this patient group.

References

A surprising new study makes the case for a low-protein diet | Prevention
Study finds healthy eating patterns matter more than individual foods | Mens Fitness
AFib patients who exercise live up to 1.2 years longer, 87,000-person study shows | Tech Times

7. Experts advocate individualized application of dietary and exercise findings

So make sure your competent? doctor gives you EXACT PROTOCOLS ON THIS! You do want to blame your doctor for failure to meet these health needs, right!

Medical and nutrition experts agree that new research findings should be applied in a balanced and individualized manner. They stress that personal health needs and conditions should guide dietary and exercise decisions rather than adopting extreme changes.

References

A surprising new study makes the case for a low-protein diet | Prevention
Study finds healthy eating patterns matter more than individual foods | Mens Fitness

8. Dual fatty acid engineering used in GLP-1 drug design

The biweekly GLP-1 drug incorporates dual fatty acid engineering in its formulation. This design approach is intended to influence the drug's pharmacological properties, such as duration of action.

References

Biweekly GLP-1 drug clears first human test via dual fatty acid engineering | Tech Times

Reduced Protein Consumption Linked to Better Health and Longer Lifespan: Study

 

Whoa! Goes against everything we've been hearing about protein lately. Ask your doctor to clarify. Can your doctor get you active enough(100% recovered?) to need more protein?

Reduced Protein Consumption Linked to Better Health and Longer Lifespan: Study

New research reshapes approach to muscle, strength and protein

 Will this change your doctor's protocols on these? OH sorry, your incompetent? doctor has no protocols for you at all! You're supposed to recover by focusing on energy from the ether!

New research reshapes approach to muscle, strength and protein

New research reshapes approach to muscle, strength and protein

Size isn’t everything: Studies show technique, leverage, and neural adaptation can let smaller athletes outperform bigger ones in strength tests.

Protein myths busted: Experts say most healthy people need less protein than popular advice suggests, and timing is less critical than total daily intake.

Over 50 strength: A new Women’s Health plan offers a science-based, sustainable path for women in midlife to build muscle, improve health, and maintain mobility.

1. Role of Skill, Leverage, and Neural Efficiency in Strength

Strength performance is heavily influenced by factors such as technical skill, biomechanical leverage, and neural efficiency. These factors can enable individuals with smaller muscles to outperform larger counterparts in certain lifts.

2. Training Recommendations for Size Versus Strength Goals

For muscle size, higher training volume is recommended, while for strength, heavier loads are more effective. A combination of both approaches can be used to target both size and strength simultaneously.

3. Complete protein needs can be met through varied diet over time

Dietitians emphasize that it is not necessary to consume all essential amino acids in a single meal. A varied diet over the course of a day can provide complete protein for healthy adults.

4. Muscle building potential for women over 50

Women over the age of 50 are capable of building muscle. This challenges assumptions that significant muscle growth is not possible in this demographic. The statement emphasizes that age alone does not prevent strength and muscle development.

5. Prevalence of ineffective training methods among women over 50

Many women over 50 are engaging in training methods that are not optimal for building muscle. This suggests a gap between current exercise practices and the most effective, evidence-based approaches for this age group.

6. Launch of WH+ Strong After 50 Program

Women's Health has introduced the WH+ Strong After 50 program, a four-week sustainable strength training plan aimed at women over 50. The program is designed to address age-related muscle and bone loss through structured exercise and lifestyle guidance.

Protein Restriction Improves Metabolism and Longevity

 Whoa! Goes against everything we've been hearing about protein lately. Ask your doctor to clarify. Can your doctor get you active enough(100% recovered?) to need more protein?

Protein Restriction Improves Metabolism and Longevity

Summary: A major review of over 350 studies suggests that reducing protein intake improves metabolic health, reduces cellular damage, and can extend lifespan.

The review challenges recent blanket recommendations advocating higher protein consumption. While high-protein diets support muscle synthesis in active individuals and athletes, excess protein intake in sedentary populations may accelerate age-related metabolic decline.

Protein restriction triggers key anti-aging mechanisms, including the elevation of fibroblast growth factor 21 (FGF21) and reduced signaling through specific branched-chain amino acids (isoleucine, valine) and methionine, promoting metabolic efficiency and cellular preservation without requiring total caloric restriction.

Key Facts

• Broad Scientific Synthesis: Evaluates data across more than 350 published studies spanning yeast, fruit flies, rodents, and human clinical trials examining protein restriction and longevity.
• FGF21 Endocrine Axis: Identifies fibroblast growth factor 21 (FGF21) as a central metabolic driver; low protein intake elevates circulating FGF21, boosting energy expenditure, improving glycemic control, and lowering systemic inflammation.
• Key Amino Acid Drivers: Pinpoints methionine, isoleucine, and valine as primary amino acid drivers of growth signaling pathways that, when overconsumed without physical activity, promote inflammation, metabolic dysfunction, and accelerated aging.
• Calorie-Independent Benefits: Demonstrates that restricting protein intake yields weight loss, reduced fat mass, and lower fasting blood glucose in human trials without requiring overall caloric restriction.
• Activity-Dependent Nuance: Highlights that regular exercise and high physical activity insulate athletes and active individuals from the metabolic risks of high-protein diets by utilizing amino acids directly for muscle remodeling.

Source: Cell Press

Protein-fortified foods are popping up everywhere, from cereal and coffee to even protein water. But a new review covering over 350 papers on protein restriction and aging—publishing July 31 in the Cell Press journal Cell Press Blue—suggests that consuming less protein could have greater health benefits and could, in some cases, extend lifespan. The authors describe how protein restriction slows aging by improving metabolism, changing how cells respond to nutrients, reducing cellular damage, and preserving healthy cell function. 

“It’s absolutely crystal clear that there are benefits of protein to muscle growth and exercise response of active individuals,” says Dudley Lamming, the paper’s corresponding author, of the University of Wisconsin-Madison. “But because most people are relatively sedentary, many people are likely consuming more protein than they actually need, which probably has negative health consequences.” 

For decades, scientists have known that eating less calories can extend lifespan in many organisms and reduce the risk of age-related diseases like cancer. But maintaining a calorie-restricted diet is difficult for most people. 

Previous studies have found that eating less protein can extend the lifespan of flies and rodents without reducing their calorie consumption. Several recent clinical trials in humans have also shown that reducing protein intake can reduce weight and fat mass and improve fasting blood sugar in humans, even though protein-restricted individuals tend to eat more calories.  

But at the same time, some studies have found that eating more protein could promote weight loss and reduce age-related muscle loss in older adults when paired with exercise. Those findings prompted US authorities to update its dietary guidelines this year, recommending an increase in daily protein intake to 1.2–1.6 grams per kilogram of body weight (0.5–0.7 grams per pound), nearly doubling the previous recommendations.   

With Americans consuming more protein than ever and older adults encouraged to boost their intake, Lamming and his colleague set off to review decades of research on protein restriction and aging. Drawing on more than 350 papers, the team outlined potential mechanisms that consistently emerge across studies and may explain how protein-restricted diets could improve health and promote longevity. These mechanisms suggest that protein restriction slows aging by improving metabolism, changing how cells respond to nutrients, reducing cellular damage, and preserving healthy cell function. 

One of the key players is a hormone called fibroblast growth factor 21 (FGF21), which rises when protein intake is low. FGF21 can increase the body’s energy expenditure, improve blood sugar control, and reduce inflammation. Studies in mice have shown that animals with higher FGF21 levels lived longer than normal mice, and the benefit was more pronounced in male mice than female mice. Eating less protein raises FGF21 levels in humans as well. 

The review also highlights several amino acids, the building blocks of protein, that appear to drive many of these effects, including methionine, isoleucine, and valine. Studies show that consuming too much of these amino acids could trigger biological processes that promote growth, increasing the risk of obesity, inflammation, and other age-related diseases.  

“These studies show that the amount of protein sedentary people are eating today may have negative health consequences, at least at the population level,” Lamming says. 

He adds that while some people, like pregnant women and some older adults, have higher protein needs, for most sedentary adults, protein-fortified food may not provide the health benefits people expect.  

Lamming notes that athletes often consume large amounts of protein without developing metabolic diseases. He suspects that regular exercise, perhaps by using protein to build strong healthy muscles, helps protect them from the negative health effects associated with a protein-rich diet. 

“Recent recommendations have encouraged people to eat more protein, but they’ve also encouraged people to exercise more,” Lamming says. “We probably need to personalize protein recommendations based not just on age, but also on how physically active people are.”  

Funding: This work was supported by the National Institute on Aging, the Wisconsin Partnership Program, and the University of Wisconsin–Madison.

Key Questions Answered:

Q: How does protein restriction improve metabolic health without cutting total calories?

A: Reducing protein intake triggers an increase in the hormone FGF21, which enhances energy expenditure, decreases systemic inflammation, and improves blood sugar control. Additionally, lowering the intake of specific amino acids like isoleucine, valine, and methionine dials back growth signaling pathways that otherwise drive metabolic stress and fat accumulation.

Q: Why are high-protein diets harmful for sedentary individuals but beneficial for athletes?

A: Active individuals and athletes rapidly utilize ingested amino acids to repair and synthesize muscle tissue, neutralizing excess metabolic stress. In sedentary individuals, unneeded amino acids overstimulate nutrient-sensing growth pathways, which can lead to insulin resistance, metabolic dysfunction, and accelerated cellular aging.

Q: Should older adults automatically lower their protein intake based on this review?

A: Not necessarily. Nutritional needs are highly individualized; older adults facing age-related muscle loss (sarcopenia) or pregnant women often require higher protein levels, particularly when paired with resistance exercise. The review emphasizes that dietary protein guidelines should be personalized based on physical activity levels and specific physiological demands rather than applied as a single population-wide target.

Editorial Notes:

• This article was edited by a Neuroscience News editor.
• Journal paper reviewed in full.
• Additional context added by our staff.

About this diet and aging research news

Author: Julia Grimmett
Source: Cell Press
Contact: Julia Grimmett – Cell Press
Image: The image is credited to Neuroscience News

Original Research: Open access.
“The Hallmarks of Protein and Amino Acid Restriction in Aging and Longevity” by Bailey A. Knopf, Dudley W. Lamming. Cell Press Blue
DOI:10.1016/j.cpblue.2026.100079