By Dr. Alex Armitage, DNP, CNL, APRN, FNP-BC Specialist in Supportive Palliative Care and passionate advocate for holistic well-being.
Index:
I read a lot of the medical literature, sometimes for work, sometimes just for fun. I like to see what others are doing in medicine and the scientific community. Just published this month, February 2024, is a crucial article from the Nurse’s Health Study Cohort underscoring the importance of adequate protein intake for cognitive health. Reading this study this morning it got me thinking about 2 facts:
Most of us don’t eat enough protein, and
This statement becomes even more true as we age
Protein is foundational to good health
But how much? Read on...
Food Has Become Political and We Have Been Eating a Lie!
In the U.S., more than 93% of adults suffer from high blood pressure, blood sugar, and elevated cholesterol. Many of us struggle with being overweight and obesity rates have soared. Cardiovascular disease is our primary killer. That’s not our fault.
Instead of empowering us with knowledge and healthy choices, we’re bombarded with ads and misleading labels. For years, the food industry has saturated the market with processed foods and ultra-processed foods that are low in essential nutrients, prioritizing profits over public health.
Amidst this deluge of unhealthy options, the quest for nutritious choices becomes a daunting task. Advertisements and misleading labels cloud our judgment, transforming the simple act of choosing what to eat into a labyrinth of confusion. The barrage of nutritional information and labels only adds to the chaos, leaving us more bewildered about our dietary choices than ever before. In this cluttered nutritional landscape, one beacon of clarity shines through the fog: the critical role of protein in our diet.
The evidence is mounting that good clean protein has a profound significance on how we age. As our bodies face there is the inevitable decline of muscle mass and strength—a condition known as sarcopenia. This decline isn't just about losing muscle; it's about losing our independence, mobility, and the resilience to bounce back from illnesses and injuries. We have data that directly correlates muscle mass with longevity (see articles below for the full links)
Why Eat Protein? Top 10 Reasons in a Nutshell
Optimal protein intake plays a pivotal role in supporting overall health and well-being as we age. Here’s a list of the top 10 benefits:
Maintains Muscle Mass and Strength: Helps counteract age-related muscle loss (sarcopenia), crucial for mobility, balance, and overall functionality.
Supports Bone Health: Contributes to bone density and strength, reducing the risk of osteoporosis and fractures.
Enhances Metabolic Health: Aids in maintaining a healthy metabolism and can assist in weight management by preserving muscle mass, which is more metabolically active than fat tissue.
Promotes Healing and Recovery: Vital for the body's repair processes, aiding in quicker recovery from wounds, surgeries, or illnesses.
Bolsters Immune Function: Essential for the production of antibodies and immune cells, helping to defend against infections and diseases.
Supports Cognitive Function: This may help in maintaining cognitive health and reducing the risk of cognitive decline and dementia through various mechanisms, including stabilizing blood sugar levels and providing essential amino acids for neurotransmitter synthesis.
Optimizes Nutrient Utilization: Aids in the absorption and utilization of other nutrients, such as vitamins and minerals, essential for various bodily functions.
Enhances Mood and Mental Health: Certain amino acids from protein are precursors to neurotransmitters involved in mood regulation, such as serotonin and dopamine.
Supports Cardiovascular Health: Some protein sources, especially plant-based proteins, are associated with lower blood pressure and reduced risk of heart disease.
Improves Sleep Quality: Some studies suggest that adequate protein intake, especially from sources rich in certain amino acids, can improve sleep quality and duration.
Incorporating a variety of protein sources into the diet, including both animal and plant-based proteins, can help achieve these benefits. Older adults need to focus not just on the quantity but also on the quality and timing of protein intake to maximize health outcomes and support successful aging.
Why Do I Need More Protein as I Get Older: Protein and Aging?
1) Anabolic Inefficiency
As we age, we experience a reduced ability to synthesize new muscle tissue from protein. Anabolic processes are those that build organs and tissues, including muscle protein synthesis, which is crucial for maintaining muscle mass and strength. Over time our bodies become less efficient at processing and using dietary protein to build and repair muscle tissue. This reduction in anabolic responsiveness means that even when adequate protein is consumed, the body is not as capable of converting it into muscle mass as efficiently as it did in younger years. This inefficiency contributes to age-related muscle loss, known as sarcopenia, making it necessary for older adults to consume more dietary protein to stimulate muscle protein synthesis sufficiently and counteract the loss of muscle mass and function.
2) Increased Splanchnic Extraction
Splanchnic extraction refers to the process by which nutrients, including amino acids from dietary protein, are absorbed and then metabolized or used by the splanchnic organs (the stomach, intestines, liver, spleen, and pancreas) after ingestion. This process is significant because it determines how much of the ingested nutrients bypass the splanchnic region and become available to the rest of the body, such as the muscles and other tissues, for protein synthesis and other metabolic functions.
As we age, the efficiency of this process can change. An increased splanchnic extraction means that a higher proportion of ingested protein is retained or used up by these organs and less is available for muscle and other peripheral tissues. This can contribute to the challenges older adults face in maintaining muscle mass and function, necessitating higher overall dietary protein intake to compensate for these age-related changes in nutrient metabolism and distribution.
How Much Protein Should I Eat?
The consensus from various studies emphasizes the importance of not only meeting but exceeding the current Recommended Dietary Allowance for protein in older individuals to support skeletal muscle health and overall well-being. The current recommended dietary allowance for protein (0.8 g/kg/day) is now thought be inadequate for maintaining muscle health in older adults by many nutritional experts.
Recommendations vary, but digging into the medical literature and according to protein metabolism experts, an average daily intake in the range of 1.0 to 1.2 g/kg body weight per day for older adults (>65 years), with higher intakes (1.3 – 1.8 g/kg body weight/day) advised for those engaging in exercise or being otherwise active, or if you have acute or chronic.
Caution if you have certain medical conditions such as kidney disease or Parkinson's Disease
Individuals with severe kidney disease not on dialysis, may need to limit protein intake. If this is you please speak with your nephrologist for guidance.
Individuals with Parkinson's disease need to pay attention to timing of protein intake. Protein can interfere with the absorption of levodopa. For this reason, if you have Parkinson's Disease separate your meals from medication by at least an hour and if you are having significant difficulty moving you may want to eat most of your protein in the evening when you are less active. The type of protein that you eat if you have Parkinson's disease is very important, as dairy is not generally recommended and plant-based protein sources are more favorable. This warrants a longer conversation that is beyond this article.
Let's Do The Math
So for a man who is 180 lbs (82 kg), his minimum protein intake should be above 100g a day, probably closer to 150 – 180 g a day if he is active. This is not as easy as it sounds! Try it yourself – spend a day tracking your protein intake and it may surprise you as to how hard these goals are to achieve.
Here’s a fun little calculator if you would like to play around with protein intake numbers for yourself and your loved ones https://www.calculator.net/protein-calculator.html
Optimal Protein Intake Per Meal
To maximize muscle protein synthesis, each meal should contain approximately 25–30 g of protein, with 1-2 high-protein snacks. Muscle protein synthesis in the elderly may be blunted when the quantity of protein is less than approximately 20 g per meal, or the amino acid leucine is not taken in high enough quantities. Given the role of leucine as the master dietary regulator of muscle protein turnover, the ingestion of protein sources enriched with this essential amino acid, or its metabolite β-hydroxy β-methylbutyrate, is thought to offer the greatest benefit in terms of preservation of muscle mass and function in old age. It is possible to supplement with leucine if your intake is not high enough, but if you hit the 30g protein/meal target you should be fine.
When Should I Eat Protein?
1) Spread Your Intake Throughout the Day
The traditional dietary pattern in many cultures tends to be carb-heavy in the morning and protein-heavy in the evening. However, research suggests that for maintaining muscle mass and overall health, a more balanced approach is beneficial. Distributing protein intake evenly throughout the day can ensure a constant supply of amino acids and lead to more efficient muscle protein synthesis.
Start the day with a protein-rich breakfast, such as eggs, Greek yogurt, or a protein smoothie.
Include a source of protein in every meal and snack, like chicken, fish, legumes, or nuts.
Consider the quality of protein, opting for sources that provide all the essential amino acids.
2) Post-Exercise
The timing of protein intake relative to physical activity is another critical consideration. Consuming protein shortly after exercise is particularly beneficial for muscle repair and growth. This window of opportunity, often referred to as the "anabolic window," is a period when the muscles are particularly receptive to nutrients, and protein can be utilized most effectively for recovery and growth.
Why is post-exercise protein important? Exercise, especially strength training or endurance activities, causes micro-tears in muscle fibers, which need to be repaired. Providing protein after such activities supplies the necessary building blocks (amino acids) for muscle repair and growth, enhancing recovery, and improving strength and muscle mass over time. This is the best way to build muscle: a combination of exercise and protein!
Aim to consume protein within 45 minutes to an hour after exercise. This timing helps maximize the body’s ability to use protein for recovery and muscle building.
Key Findings from the Study
So this brings us back to the study that I was reading this morning on the need for protein in healthy aging, which concluded that plant-based proteins have some advantages over animal-based proteins. The study highlights several critical points:
A higher protein intake was associated with greater longevity and quality of life.
Not all protein sources affect health outcomes equally.
Plant protein intake showed more favorable associations with healthy aging, including reduced chronic disease incidence, better physical function, and improved mental health status.
Substituting plant protein for animal or dairy protein, carbohydrates, or fats was associated with improved odds of healthy aging, indicating that not only the amount but also the source of protein is crucial for health outcomes.
What Does This Mean For Me?
Eat A Variety of Protein But Favor Plants:
Eating a variety of protein sources, particularly plant-based proteins such as legumes, nuts, seeds, and whole grains, can be beneficial. These foods not only provide essential amino acids but also deliver other nutrients and compounds, like fiber, vitamins, minerals, and polyphenols, which collectively contribute to health and well-being.
Moderation in Animal Protein Consumption:
Given the study's findings, moderating the intake of animal proteins, particularly red and processed meats, might be advisable.
Strategic Substitutions Go a Long Way:
Substituting plant proteins for animal proteins or less healthy macronutrients (like refined carbohydrates) is recommended. So eat nuts, bean, seeds, chickpeas instead of hamburgers, pizza or chips.
Here are some common sources, with those particularly rich in leucine highlighted for their notable contribution to stimulating muscle protein synthesis:
Animal-Based Protein Sources
Chicken breast: A lean source of protein that's versatile in recipes.
Turkey: Another lean protein, especially breast meat.
Eggs: Contain all essential amino acids, making them a complete protein source.
Greek yogurt: Offers a high protein content with beneficial probiotics.
Cottage cheese: High in protein and calcium.
Fish (e.g., salmon, tuna): Rich in protein and omega-3 fatty acids.
Beef: Especially lean cuts, high in leucine.
Pork: Lean cuts like tenderloin are good protein sources; pork is rich in leucine.
Plant-Based Protein Sources
Lentils: A versatile and protein-packed legume.
Chickpeas: Can be used in a variety of dishes, from salads to hummus.
Black beans: A staple protein in many cuisines around the world.
Quinoa: A complete protein, containing all nine essential amino acids.
Tofu: Made from soybeans, tofu is a staple protein in many vegetarian and vegan diets.
Tempeh: Another soy-based product, rich in leucine.
Edamame: Young soybeans, high in leucine, and can be enjoyed as a snack or added to dishes.
Peanuts and peanut butter: While higher in fat, they're good protein sources and have a notable leucine content.
Dairy and Dairy Alternatives
Milk: A traditional source of protein and calcium.
Cheese: Hard cheeses like Parmesan are rich in leucine.
Whey protein: A by-product of cheese making, exceptionally high in leucine, often used in supplements and shakes for muscle building.
Nuts and Seeds
Almonds: Offer a good amount of protein per serving.
Pumpkin seeds: A high-protein snack that's also rich in minerals.
Chia seeds: These can be added to smoothies or yogurt for a protein boost.
Inspiration!
So as I write this article today I have the slow-cooker going because I will not have much time in the kitchen. Let me share one of my favorite dump-it-all-together recipes for a high-protein crockpot Taco soup. You cannot get simpler than this. Use any ground meat that pleases you (or a plant-based substitute) and garnish with various toppings of avocado, cheese, sour cream, green onions, and cilantro – Oh, so good! For my friend, T – this is barely cooking!!! (but it still counts as real food.)
My blessing for you today
Happy cooking! I hope that being in the kitchen reduces any stress, brings you a sense of achievement, allows for bonding with your loved ones when you feed them, and brings you a long and healthful life!
Additional reading for geeking out!
Ardisson Korat, A. V., Shea, M. K., Jacques, P. F., Sebastiani, P., Wang, M., Eliassen, A. H., Willett, W. C., & Sun, Q. (2024). Dietary protein intake in midlife in relation to healthy aging – results from the prospective Nurses’ Health Study cohort. The American Journal of Clinical Nutrition, 119(2), 271-282. Link
Srikanthan, P., & Karlamangla, A. S. (2014). Muscle mass index as a predictor of longevity in older adults. The American journal of medicine, 127(6), 547–553. Link
Wang, H., Hai, S., Liu, Y., Liu, Y., & Dong, B. (2019). Skeletal muscle mass as a mortality predictor among nonagenarians and centenarians: A prospective cohort study. Scientific Reports, 9, Article 2420. Link
Bauer, J., Biolo, G., Cederholm, T., Cesari, M., Cruz-Jentoft, A. J., Morley, J. E., Phillips, S. M., Sieber, C., Stehle, P., Teta, D., Visvanathan, R., Volpi, E., & Boirie, Y. (2013). Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. Journal of the American Medical Directors Association, 14(8), 542-559. Link.
Baum, J., Kim, I.-Y., & Wolfe, R. (2016). Protein consumption and the elderly: What is the optimal level of intake? Nutrients, 8(6), 359. Link
Paddon-Jones, D., & Rasmussen, B. (2009). Dietary protein recommendations and the prevention of sarcopenia. Current Opinion in Clinical Nutrition and Metabolic Care, 12(1), 86–90. Link
Landi, F., Calvani, R., Tosato, M., Martone, A. M., Ortolani, E., Savera, G., D’Angelo, E., Sisto, A., & Marzetti, E. (2016). Protein Intake and Muscle Health in Old Age: From Biological Plausibility to Clinical Evidence. Nutrients, 8(5), 295. Link