Muscle men aren’t the only ones needing to load up on more protein. Recent evidence suggests that the current Recommended Dietary Allowance (RDA) for protein, which is 0.8 gram per kilogram of body weight per day for healthy adults over age 19, is too low for elderly people and those who engage in high volumes of aerobic activity. A May 2017 Frontiers in Nutrition paper makes a strong argument that older adults can have lower rates of muscle and function loss with protein intakes of 1.2–1.5 g/kg BW/day.

Similarly, Canadian and Japanese researchers published a study in PLOS One in 2016 which determined that the protein requirements for endurance athletes should be set at 1.2–1.4 g/kg BW/day to meet the metabolic demands of training. Endurance activities like cycling and running can damage muscles and increase the use of muscle protein for energy needs, both of which boost the call for protein at the dinner table. These groups can get their fill by eating protein-rich foods at every meal and seeking out foods that provide leucine, an amino acid that is especially important at maintaining and building lean body mass. Leucine is in dairy, meats, eggs, soy products (edamame, tofu), beans and whey protein powder.

Editor’s note: See the Research column in the October 2017 for an overview
of protein supplements.