An exploratory nutrition study found inadequate protein intake among vegan, vegetarian and omnivorous adults in their 70s, with the largest shortfalls among vegans and additional concerns involving protein quality, calorie intake and key vitamins and minerals.
By yourNEWS Media Newsroom
Older adults may struggle to consume enough protein regardless of whether they eat meat, vegetarian foods or an entirely plant-based diet, according to a new exploratory study that found protein intake below the recommended dietary allowance across all three dietary groups.
The research, published in The Journal of Nutrition, found that 83% of vegan participants consumed less protein than the recommended dietary allowance, compared with 40% of vegetarians and 25% of omnivores.
Although the largest shortfall occurred among vegans, researchers emphasized that inadequate protein consumption was not confined to plant-based diets and is consistent with previous findings showing that insufficient protein intake is common among older adults.
That concern becomes increasingly important with age because maintaining adequate protein and energy intake helps preserve muscle mass, strength and physical function.
The study examined adults between ages 72 and 80 who had maintained their dietary patterns for years or decades.
Twenty participants were vegetarians and six were vegans. The vegetarian participants had followed their diets for a median of 42 years, while the vegan participants had eaten vegan diets for approximately 10 years after previously following vegetarian diets for about 31 years.
Participants documented everything they consumed for three days, including food and beverages.
Researchers then evaluated total calorie intake, overall protein consumption, the quality of protein eaten at individual meals and across the full day, and intake of several vitamins and minerals.
One of the clearest findings involved the difference between simply consuming protein and consuming protein containing sufficient amounts of essential amino acids.
Protein quality was generally lower among the plant-based groups, particularly when individual meals were examined.
Lysine and methionine were the amino acids most likely to limit protein quality, according to the study.
The pattern also varied according to the time of day.
Breakfast generally had the lowest protein-quality scores, lunch ranked higher and dinner provided the strongest protein quality.
That finding suggests that concentrating most dietary protein at the end of the day may leave earlier meals with insufficient quantities or combinations of essential amino acids.
The researchers nevertheless found that vegan meals could provide high-quality protein when foods were appropriately selected.
Some vegan breakfasts containing combinations of tofu, soy yogurt, soybeans, nuts, seeds and whole grains achieved high protein-quality scores.
The results therefore did not indicate that high-quality protein necessarily requires animal foods. Instead, they highlighted the importance of both the amount and composition of meals, particularly for older adults whose total food intake may already be declining.
Calories presented another issue.
Vegan participants consumed significantly less total energy than omnivores, according to the study.
That finding matters because consistently eating too little can make it difficult to obtain enough protein, vitamins and minerals even when the foods consumed are nutrient dense.
Older people may be especially vulnerable to inadequate energy intake because appetite can decline with age while the body’s need to preserve muscle and physical function remains.
The study used the current protein recommended dietary allowance of 0.8 grams per kilogram of body weight per day when assessing inadequacy.
Researchers and nutrition specialists have increasingly questioned whether that amount is sufficient for all older adults.
A scientific review from McMaster University published in Frontiers in Nutrition concluded that current daily protein recommendations may not adequately meet the needs of elderly and critically ill adults.
Some researchers and nutrition specialists recommend substantially higher intake for older adults, with suggested levels commonly ranging from approximately 1.2 to 1.6 grams of protein per kilogram of body weight per day to help counter age-related muscle loss.
A NaturalNews.com report has also highlighted that range while emphasizing the importance of distributing protein throughout the day and combining adequate intake with resistance exercise.
Resistance training is particularly important because protein alone cannot fully prevent the decline in muscle that occurs as people age.
That progressive loss of muscle mass and function is known as sarcopenia.
Muscle loss can progress at approximately 0.8% of skeletal muscle per year beginning around the fifth decade of adulthood, according to research summarized in the source material.
Sarcopenia has an estimated prevalence of about 10% among adults older than 60 and may affect more than half of people older than 80.
That makes adequate protein intake increasingly consequential as people move through their 70s and 80s.
The new study also identified nutritional concerns extending beyond protein.
None of the vegan participants met recommended intake levels for calcium, iron, zinc, folate, vitamin B12 and vitamin D.
Vegetarians generally consumed adequate amounts of iron and folate but showed shortfalls involving several other micronutrients.
Omnivorous participants were not free of nutritional deficiencies either, reinforcing the researchers’ conclusion that dietary adequacy cannot be assumed solely from whether someone consumes animal products.
Supplements were commonly used across all three groups.
Vitamin B12 is one nutrient of particular concern among older adults.
It is required for red blood cell formation, neurological function and DNA synthesis, and the body’s ability to absorb B12 can diminish with age.
A Mercola.com report cited U.S. Department of Agriculture data indicating that nearly 40% of the U.S. population has marginal vitamin B12 status and approximately 9% is deficient.
Strict vegans face an additional challenge because naturally occurring vitamin B12 is found primarily in animal-derived foods, making fortified products or supplementation particularly important.
Zinc was another nutrient examined.
Zinc is present throughout the body’s tissues, organs and fluids and is described as the second-most abundant trace mineral in the human body after iron.
It contributes to immune activity, wound healing, protein synthesis and numerous enzymatic processes.
The broader problem of obtaining sufficient calories while still falling short of essential micronutrients is sometimes described as “hidden hunger.”
The World Health Organization uses the term to describe situations in which the quality of a person’s diet fails to provide sufficient vitamins and minerals even when enough food may be available. Approximately 2 billion people worldwide experience vitamin and mineral deficiencies, according to information cited in a NaturalNews.com report.
For older adults, the new study suggests that addressing nutritional gaps may require looking beyond the total amount of food eaten.
The researchers’ meal-by-meal analysis indicates that protein distribution could also matter.
Instead of consuming relatively little protein at breakfast and lunch followed by a large portion at dinner, older adults may benefit from including a meaningful protein source throughout the day.
A separate study published in the American Journal of Clinical Nutrition found that distributing protein more evenly across three daily meals may help maintain muscle strength in older men and women.
Practical options depend on dietary preferences.
For people who consume animal products, protein sources can include eggs, Greek yogurt, cottage cheese, poultry and fish.
Plant-based options include tofu, tempeh, soy foods, beans, lentils, nuts, seeds and appropriately combined whole grains.
Breakfast may warrant particular attention because it was the meal with some of the weakest protein-quality scores in the new study.
Possible higher-protein breakfasts include Greek yogurt with nuts and seeds, eggs with whole-grain toast or tofu scrambled with other plant foods.
For people with small appetites, a protein supplement may provide another way to increase intake without requiring a large meal.
Supplementation, however, does not eliminate the importance of consuming enough total calories.
If an older adult chronically undereats, adding isolated protein while overall energy intake remains too low may still leave deficiencies in vitamins, minerals and other nutrients.
The study’s small size is an important limitation.
Because it was exploratory and included only 26 vegetarian and vegan participants in the specified age range, its percentages should not be interpreted as estimates of how frequently protein deficiency occurs among all vegans, vegetarians or omnivores.
Three days of food records also provide only a limited snapshot of a person’s habitual intake.
The results instead identify dietary patterns that warrant further investigation and reinforce broader research showing that older adults frequently fail to consume enough protein.
The strongest lesson may therefore be broader than the comparison between plant-based and omnivorous diets.
Older adults following any dietary pattern can fall short if they consume too little food, concentrate protein in one meal or rely on foods that do not provide sufficient quantities of essential amino acids and micronutrients.
Plant-based diets require particular attention to protein quality and nutrients such as vitamin B12, iron, calcium, zinc and vitamin D, but eating meat does not automatically guarantee adequate nutrition.
For people seeking to preserve strength as they age, the findings point toward a combination of adequate calories, protein at multiple meals, attention to protein quality and regular resistance exercise rather than reliance on any single food or dietary label.
Explainer Infographic
Comments