Dietary Recommendations for Midlife Patients
Physicians should therefore advise midlife patients to meet or perhaps modestly exceed the recommended dietary allowance (RDA) for protein of 0.8 g/kg per day and to make plant protein a substantial component of daily dietary protein intake, Dr. Dirschl said.
Dr. Luke D. Kim
Luke D. Kim, MD, MEd, a geriatrician at the Cleveland Clinic in Cleveland, Ohio, noted that patients with lower socioeconomic status or with difficulty in day-to-day functioning are likely to have suboptimal protein intake. Such patients may need encouragement to eat more protein. “But we should keep in mind that showing a higher associated odds ratio of better health with increased protein take does not mean causality,” he said.
According to Rachel L. Amdur, MD, an internist at Northwestern Medicine in Chicago, Illinois, the long-term follow-up data from the NHS are uniquely helpful. “Middle-aged persons may think they no longer need much dietary protein and need to be reminded. Sometimes eating carbohydrates is just easier,” she said in an interview. Physicians need to asses and counsel patients on nutrition at all stages of life. “As I tell my patients, it’s best to think of your future self now.”
In agreement is Louis J. Morledge, MD, an internist at Northwell Health in New York City. “I firmly counsel my patients about adequate and often increased protein intake in middle life. But this is always within a larger framework of overall nutritional health.” He added that middle-aged persons often find themselves “stuck in food ruts,” and one of his clinical focuses is to advise patients about the importance of healthier food choices so they can better adjust to mental, emotional, physical, and skeletal changes as they age.
Study Details
The NHS analysis drew on prospective data from 48,762 nurses under age 60 in 1984. Total protein, animal protein, dairy protein, and plant protein were derived from validated food-frequency questionnaires.
Adjusting for lifestyle, demographics, and health status, the investigators identified 3721 (7.6% of cohort) eligible participants. The mean age of participants at baseline was 48.6 years; 38.6% had body mass indexes (BMI; in kg/m2) greater than 25; 22.9% were current smokers; and 88.2% were married.
Healthy aging was defined as freedom from 11 major chronic diseases, good mental health, and no impairments in cognitive or physical function, as assessed in the 2014 or 2016 NHS participant questionnaires. Diseases/treatments included cancer, type 2 diabetes, myocardial infarction, coronary artery bypass graft or coronary angioplasty, congestive heart failure, stroke, kidney failure, chronic obstructive pulmonary disease, Parkinson disease, multiple sclerosis, and amyotrophic lateral sclerosis.
Mean total protein consumption as a percentage of energy was 18.3% (standard deviation 3%), slightly higher than the average 16% in the US diet. Of this, 13.3% derived from animals, 3.6% from dairy products, and 4.9% from plants.
Total protein intake was positively associated with higher education levels, being physically active, higher BMI, and a baseline history of hypertension and hypercholesterolemia. Conversely, total protein intake was inversely associated with intakes of total carbohydrates, nuts, alcohol, and sugar-sweetened beverages.
The associations between protein intake and healthy aging are complex and not fully understood, the authors stated.