Protein has long been linked with building and maintaining muscle, which is why many people turn to powders and supplements to raise their intake. But for older adults, new findings suggest that approach may not deliver the muscle gains some expect.
Protein is a key part of overall health and is essential for repairing tissue and supporting normal cell function, according to Better Health.
Even so, plenty of people do not give much thought to how much protein they actually get through food each day.
That matters even more for anyone focused on improving physical strength, preserving muscle, or supporting long-term wellbeing.
The Mayo Clinic notes that protein requirements are not identical for everyone, with needs changing depending on factors such as sex and age.
Now, research has highlighted an age group for whom protein supplementation may offer less benefit than many assume when it comes to increasing strength and muscle mass.
A Tufts University study published in 2026 found that adults over 65 did not appear to gain added benefits from taking whey protein supplements on their own to meet protein targets.
The study focused on otherwise healthy older adults and looked at whether extra whey protein, by itself, could improve muscle mass and strength over time.
In the trial, 141 participants aged over 65 took part. One group received whey protein supplements over a 24-week period, while another was given a placebo.
Researchers then assessed the participants using a range of measures designed to track muscle and strength changes, including balance tests, leg press exercises, and body scans before and after the trial.
By the end of the study, blood work showed that the supplement group had increased levels of the growth-related hormone IGF-1. Despite that, they did not show extra gains in muscle mass, a result that surprised the team behind the research.
Why might that be the case?
One explanation could relate to age-related muscle decline, a condition associated with reduced strength, poorer balance, and a higher risk of falls and fractures in older adults, according to Verywell Health.
Protein still plays an important role here because it can help preserve muscle and support strength. However, that does not necessarily mean it will rebuild lost muscle mass once that decline is already happening. In some cases, it may simply help slow further deterioration rather than reverse it.
Experts also stress that protein is only one piece of the puzzle. Resistance exercise remains one of the most effective ways to stimulate muscle growth, and protein appears to work best when it is paired with physical training rather than used as a stand-alone fix.
The Mayo Clinic says protein should make up around 10 to 35 percent of a person’s total daily calories.
For the average adult, the general guideline is 0.8 grams of protein per kilogram of body weight.
From around ages 40 to 50 onward, that recommendation may need to rise because of sarcopenia, the age-related loss of muscle mass.
Because of that, people in this age range who are not especially active may need roughly 1 to 1.2 grams per kilogram each day.
For those who exercise regularly, the suggested range increases to about 1.1 to 1.5 grams per kilogram.
Some experts recommend that older adults spread protein intake across meals rather than loading it all into one sitting, since the body’s muscle-building response can become less efficient with age.
Anything above two grams per kilogram is considered excessive.
That does not mean protein powder is useless. It can still be a convenient way to help older adults reach daily protein goals, especially if appetite is low or meals are hard to prepare. But the latest findings suggest the bigger payoff may come from combining enough protein with regular strength training, adequate calories, and overall healthy eating rather than relying on supplements alone.