Is Protein the Key to Healthy Aging?

• Research suggests that protein may help us age more healthfully.
• Plant-based protein, in particular, seems to be linked to positive physical and mental health outcomes.
• However, eating too much protein can lead to health problems like constipation and even kidney damage.

Protein, carbs, fats, fiber—chances are, you know the basic components of a nutritious diet. But one might be more important than you realize, especially if you’re getting older.

New research published in the American Journal of Clinical Nutrition shows that protein might be key for healthy aging. The study included data on 48,762 female nurses who are part of a long-term health study. They were all middle-aged (30–55) at the start of the study, and surveyed about their physical health, diet, and mental and cognitive health every two years until 2014 or 2016.

The findings suggested that higher protein consumption was strongly linked to healthy aging, with plant-based proteins showing the most benefits.

What Counts as ‘Healthy’ Aging?

For the study, “healthy aging” was defined as having good mental health, no memory or physical impairments, and being free of 11 major chronic diseases, including:¹

• Cancer (with the exception of melanoma skin cancer)
• Type 2 diabetes
• Myocardial infarction (heart attack)
• Coronary artery bypass graft surgery or coronary angioplasty
• Congestive heart failure
• Stroke
• Kidney failure
• Chronic obstructive pulmonary disease (COPD)
• Parkinson’s disease
• Multiple sclerosis
• Amyotrophic lateral sclerosis (ALS)

At the end of the study, about 7.6% of the participants were considered to be part of the “healthy aging” group.

The researchers noted that the participants who ate more plant-based protein were 46% more likely to age healthily than those who ate more meat and dairy protein, who were 6% less likely to stay healthy as they aged.

The only age-related health benefit linked to eating more animal protein in the study was better mobility—but eating more animal-based protein was also linked to an increased risk for chronic disease.¹

Why Protein Helps You Age Well

In the study, higher protein intake was associated with positive age-related health outcomes like maintained muscle mass and less frailty. While the link isn’t totally clear, one thought is that protein could trigger muscle-building chemicals.

Protein may help offset sarcopenia, the loss of muscle mass and function that naturally occurs as people age, Sara Chatfield, RDN, MPH, a registered dietitian nutritionist at Health Canal, told Verywell. According to Chatfield, including 25–30 grams of high-quality protein at each meal may help prevent sarcopenia.

Protein may have big brain benefits, too—even helping protect against cognitive decline. Sarah Hormachea, MS, RD, BC-ADM, CDCES, a registered dietitian at Nourish, told Verywell that protein may strengthen cognitive function by shoring up brain cell structure.

“Neurotransmitters, like serotonin and dopamine, are made from tiny protein molecules called amino acids. These chemical messengers help regulate our mood, focus, memory, and cognition,” said Hormachea. “Proteins are essential building blocks for our brain cells. They give structure to the cellular membrane. Antioxidant proteins can help protect against oxidative stress and inflammation, which is known to cause cognitive decline.”

The study also found that higher plant-based protein consumption was positively linked to not just physical but also mental health outcomes.

All Protein Is Not Created Equal

When you think of protein, animal products like meat might come to mind first, but there are many plant-based proteins, too.

Chrissy Arsenault, RDN, a registered dietitian at Kori Krill Oil, told Verywell that plant-based proteins may offer the nutritional benefits you need without the downsides of animal protein that you may be trying to avoid.

“When people replaced animal protein with plant protein, they had a lower risk of chronic disease, had good physical function, and maintained good mental health—and thus aged healthily,” said Arsenault.

So, how much protein you eat isn’t all that matters—the type does, too. “If you consume a lot of red and processed meats with high amounts of saturated fat, these fats can be harmful to your health and put you at higher risk for heart disease, among other chronic diseases,” according to Arsenault.

Your best bet is to diversify your protein sources. While it’s true that red meats do contain the most bioavailable amino acids (meaning your body can easily use them), other protein sources like fish, poultry, dairy, and legumes are packed with important micronutrients that support your health, so it’s worth including them in your diet.

Chatfield agreed, adding that since most Americans already get plenty of protein in their diets, “it’s more helpful to focus on spreading out protein intake and choosing a healthy protein at each meal. Focusing on more plant-based foods may benefit mental and physical health in older age, along with other essential nutrients, fiber, and beneficial antioxidant-rich plant compounds.”

How Much Protein Do You Need—and How Much Is Too Much?

Dietary guidelines are a little different depending on factors like your age and how active you are, but the USDA recommends 5 to 6 ounces of protein per day for women aged 60 and older, and 5.5 to 6.5 ounces of protein for men of the same age.

According to Hormachea, since the overall caloric requirements for older adults are lower, protein accounts for more of their total intake.

That said, there is such a thing as eating too much protein, and excessive protein can cause constipation and kidney problems. Extra protein is eliminated through urea, a component of urine. When there is too much protein in the body, the kidneys may struggle to keep up, leading to dehydration and even permanent kidney damage.

“It’s important to couple higher protein intake with adequate fiber and fluids. There is no additional benefit to consuming more than 2.0 grams per kilogram of body weight,” said Hormachea.

If you’re not sure how much protein you should be eating or is safe for you to include in your diet, it’s best to talk to your provider. While getting enough protein is important for your health, you want to make sure you’re not consuming more than your body needs.

Takeaway Note

Including a range of protein sources in your diet may help you age healthfully—just be sure not to eat more protein than you need or what goes beyond the recommended daily amount from the USDA or your healthcare provider.