Lately, it seems like every diet is a high-protein one. But according to new research, more than one-third of older adults still aren't getting enough protein to maintain muscle health, combat age-related weight gain, prevent the development of Type 2 diabetes and heart disease and live longer, healthier lives.

Presented at the American Society for Parenteral and Enteral Nutrition 2018 Nutrition Science & Practice Conference, the study evaluated the dietary patterns of 11,728 men and women age 51 and older. The study's researchers from Ohio State University and the Abbott health care company found that roughly 40 percent of the participants didn't meet current daily protein recommendations.

The older the subjects were, the less likely they were to get enough protein, according to the study's findings. Approximately 37.7 percent of those ages 51 to 60 years old did not meet requirements, while 46.2 percent of adults over age 70 got less than the recommended daily allowance. What's more, up to 10.7 percent of adults were at least 30 grams shy of their nutrition goals, explains Suzette Pereira, research scientist and muscle health expert at Abbott, who was not involved in the study.

While the results are pretty shocking to everyday dieters, they aren't surprising to researchers. "Both American and European cohort studies demonstrate that older adults are at risk of not meeting dietary protein recommendations," says Oliver Witard, a protein metabolism researcher and senior lecturer at the University of Stirling in Scotland.

For example, in one 2012 study published in the European Journal of Nutrition, researchers found that up to 10 percent of older Dutch adults living independently and 35 percent of those in institutional care fail to meet their daily protein targets.

Why Older Adults Still Aren't Getting Enough Protein

"Meal skipping may be part of the problem," Pereira says. In the recent study, 75 percent of the adults who met their daily protein goals ate three meals per day, while roughly 60 percent of adults who weren't getting enough protein regularly skipped at least one meal, she explains.

Witard notes that hunger levels naturally decline with age. "To compound this issue, protein-rich foods exhibit greater satiety value than carbohydrate- or fat-rich food sources," he says. In the study, older adults who did not meet their protein needs ate fewer greens, beans and dairy, but incorporated more refined and added sugars into their diet.

Appetite and fullness aside, "several other factors, including physical and mental disabilities that limit shopping, food preparation and food insecurity due to financial and social limitations may also make it difficult for older adults to consume sufficient protein," he says. Preparing protein-rich foods is often a time- and energy-intensive process, while most pre-prepared and packaged foods – a mainstay of the average American's diet – tend to be low in protein and high in refined carbohydrates, Pereira adds.

How Much Protein Is Enough?

Most people don't have a clear-cut answer on the right amount of protein needed for optimal health. "In a 2016 AARP-Abbott survey, 62 percent of adults thought they were getting enough protein, but only 17 percent knew that actual amount," Pereira says. Current federal recommendations include eating a minimum of 0.8 grams of daily protein per kilogram of a person's body mass per day. That equals about 0.36 grams of daily protein per pound of body weight or, for a 150-pound person, 54 grams of daily protein.

However, both Pereira and Witard emphasize that mounting research shows those recommendations are far from sufficient. "Your protein needs change based on things like age, gender, activity level or illness – and our current recommendations don't take that into consideration right now," she says. In a 2015 study of older adults published in the American Journal of Physiology–Endocrinology and Metabolism, those who ate double their recommended daily allowance of protein improved both their muscle protein synthesis (the process in which cells use protein to build muscle) and net protein balance, the difference between muscle protein synthesis and your muscle protein breakdown.

That's important since the average person begins breaking down more muscle than they build by age 40, according to Witard. "Thereafter, the average rate of muscle mass loss is estimated at 8 percent per decade until the age of 70 years, increasing to 15 percent per decade in octogenarians and beyond," he says. According to 2013 research review published in Muscle, Ligaments and Tendons Journal, after age 50, leg lean body mass declines by 1 to 2 percent per year, with leg strength declining 1.5 to 5 percent per year. "Hence, most individuals 70 to 80 years old possess only 60 to 80 percent of the muscle mass they had at 30 years old, declining to 50 percent in octogenarians," Witard adds.

For that reason, Witard says that older adults get 1.2 to 1.5 grams of daily protein per kilogram of their body mass. That works out to about 0.54 to 0.68 grams per pound of body weight or, for that same 150-pound person, 82 to 102 daily grams.

He also recommends spacing out proteins evenly through the day, with 2017 research published in The American Journal of Clinical Nutrition showing that adults ages 67 to 84 who spread out their protein intake throughout the day tend to have stronger, healthier muscles than those who get the bulk of their protein in one meal. A 2016 Biogerontology study co-authored by Witard found that older adults should consume 0.4 to 0.5 grams of protein per kilogram of body mass (or 0.18 to 0.23 grams of protein per pound of body weight) at each of their three daily meals. That's the equivalent of 27 to 34 grams of protein three times per day.

Why Protein Matters

A person's levels of muscle mass impacts more than strength. "Skeletal muscle is the largest organ in the body and provides the main reservoir for glucose disposal," Witard says. By helping to manage glucose, or blood sugar, muscle plays a major role in the prevention of insulin resistance and Type 2 diabetes.

"The amount of muscle you have also has an impact on health outcomes," Pereira says. "Your muscle health can impact your immunity as well as your risk of hospitalization or recovery. When you look at chronic diseases, there's a lot of emerging research in the oncology space. For example, research shows patients with cancer who have high amounts of muscle live longer because they can tolerate their chemotherapy drugs better than those with lower muscle mass." Strong muscles also help older adults maintain their mobility, independence and reduce their risk of falls and bone breaks, she adds.

Studies suggest that the cumulative effect is an overall longer, healthier life. According to 2017 research published in the peer-reviewed journal PLOS One, in men ages 40 to 90, larger mid-arm muscles (think: biceps and triceps) were significantly less likely to die from any cause within the study's 14.3-year follow-up. And, according to a 2014 the American Journal of Medicine study of 3,659 older adults, lean muscle mass was a strong predictor of longevity.

Track Your Protein Intake for Better Health

Knowing how much protein you need is not enough for good health. You also need to know how much you are getting.

To do so, try keeping a food journal. Record what you eat for each meal, adding up your grams of protein per day to see what your current average daily protein intake is and how it might need to change, Pereira says.

She explains that the protein content of packaged foods appears on their back label. When eating whole foods, which should make up the majority of your diet, you can easily find the protein content by typing your food's name and "nutrition" into a search engine such as Google. Generally, the first result will be a full nutrition panel from the U.S. Department of Agriculture. Online food trackers and apps, such as MyFitnessPal or Fooducate (available in the Apple App Store and Google Play Store), can also help.