Protein Does a Body Good
Dietary protein has many benefits. Second to water, our bodies are mainly made of protein. Athletes seek more protein because of its reputation for building muscle, but protein also builds most other tissues and feeds numerous chemical reactions that drive all manner of bodily processes. Protein gives rise to antibodies, enzymes, certain types of hormones, neurotransmitters, and much, much more.How Much Is Good?
Our need for protein is clear, but just how much and what kind of protein we need are issues of dietary debate. The recommended daily allowance (RDA) offers some guidance based on body weight. The RDA is about one-third of a gram of protein per pound of body weight for adults (about 45 grams for women, and 55 grams for men.) You could also think about it as 10 percent to 15 percent of your total daily calories.Active individuals, for example, naturally have higher protein requirements. Adding a little extra protein allows them to build back the tissue from what is broken down through activity.
What Kind of Protein Is Best?
Luckily, meeting (or exceeding) the protein RDA is well within our reach, as there are many dietary sources available. The building blocks of protein molecules are called amino acids, which are found in every living organism, from vegetables to animals and milk to fungi.Of course, not all proteins are equal—some sources deliver more of the amino acids that we need in much greater quantities.
Hundreds of different amino acids exist in nature, but the human body requires only about 20 of them. Our bodies can make 11 of these on their own when necessary, and thus they are considered “nonessential.”
Because of their complete profile of essential amino acids and relatively high number of protein grams by weight, animal sources are often considered the gold standard of protein. Plant-based foods such as rice, lentils, and broccoli also contain essential amino acids but not the complete range. A variety of vegetable sources can be combined to get all of the essential amino acids, but you will have to eat more of them to get the same amount of protein as with a smaller portion of meat.
Power of Plant Protein
According to a new study published in February in the American Journal of Clinical Nutrition, women who consume higher amounts of protein, particularly from plant-based sources, were found to develop fewer chronic diseases and were more likely to be healthier overall as they aged. Healthy aging was defined as being free from 11 major chronic diseases, maintaining good mental health, and not having certain cognitive or physical impairments.Starting in 1984, the Nurses’ Health Study began tracking nearly 50,000 middle-aged female health care professionals who were in good mental and physical condition and charted their progress until 2016. As part of their food frequency questionnaires, participants in the trial recorded details of their daily protein intake and whether it came from a plant or animal source.
HNRCA researchers observed women who didn’t develop 11 specific chronic diseases over the course of 32 years and compared them with women who did. They found that women who ate more protein saw better health outcomes overall, and among this group, those who ate more of their daily protein intake in the form of vegetables, grains, and beans, saw less heart disease, cancer, diabetes, and cognitive decline.
Greater consumption of animal protein was observed to have some correlation with better mobility as the nurses aged, and women who ate more plant proteins showed several other signs of better health long term.
HNRCA researchers found that women who obtained more of their protein from plant-based sources were 46 percent more likely to avoid chronic health problems.
Other Plant Powers
In a previous Nurses’ Health Study, greater plant protein intake in older adulthood was also associated with a lower risk of frailty and fewer functional impairments.While these studies highlight possible longevity benefits of eating more plant-based protein, keep in mind that HNRCA researchers reported no benefits in women who ate a strictly vegan diet, as the health outcomes with the best track records included some animal protein.
The study also does not suggest that plant protein is in any way superior to animal protein. Although protein was the focus of the study, HNRCA researchers concede that the results that they observed may have had more to do with factors including dietary fiber or various micronutrients.
“We cannot discount the contributions of other components of those foods that contributed to plant protein intake,” the researchers wrote.
This randomized controlled trial, published in 2023 in BMC Medicine, found that people who ate more polyphenol-rich fruits and vegetables saw better health with advancing age. The effects appeared greatest in men older than 50.
Large observational studies and randomized trials suggest that the Mediterranean diet that people have enjoyed for centuries can increase life expectancy, reduce the risk of major chronic disease, and improve quality of life and well-being.
