Yan Yu, co-founder of Snowhill Science, outlines the importance of muscle mass and protein intake in improving functional longevity. We know that lifestyle choices and factors like fasting, cardio-respiratory capacity, balance stability, sleep quality, the brain, and obesity affect longevity. However, some interesting data is surfacing regarding how our protein intake and muscle synthesis can affect our longevity.

The term macro is mentioned a lot in the context of health, weight loss, and especially for calculating one’s energy requirements and calorie intake. Macronutrients are required by our bodies in large amounts for maintaining body functions and carrying out daily activities. These are carbohydrates, proteins, and fats. Macros offer energy, or calories. While carbohydrates and proteins provide 4 calories per gram, fat provides 9 calories per gram.

Protein is a macronutrient that is essential for building muscle and tissue. We need protein in our diet intake to enable the repair of old cells and to aid in the production of new cells in the body. The basic structure of proteins consists of branches or chains of amino acids. Essentially, amino acids are the building blocks of life.

The major sources of protein are meat, eggs, and milk. Protein can be obtained from plant sources as well, such as beans, lentils, some grains, nuts, soy, vegetables, and fruits.

How much protein do we need, and why might we be under-consuming protein?

The intake of macronutrients is determined in terms of the Recommended Dietary Allowance, or RDA. It’s important to note that RDA is determined based on short term studies, typically lasting only 7 days. These tests are conducted on college-aged students, and hence RDAs should serve only as a guideline, not a rule. Additionally, it’s very difficult to measure how protein is utilized by the body, which is why one should consider the RDA for protein as the minimum amount of protein they should consume, not the ideal amount of protein to be consumed. The RDA for protein intake is 0.8 gram per kg of body weight. 

What’s the quality of the protein we should consume, and how does it matter?

We need about twice the protein intake as compared to the RDA for protein intake. The rate of muscle creation declines with age, which is why we need more protein as we age. Muscle loss is easier as we grow older due to inactivity. While underestimated, this is a serious problem. Crammed schedules, less time for exercise, a lack of proper nutritional strategies, an inactive work-life environment, fat gain, and muscle loss – all these factors contribute to muscle wastage.

Some bed rest studies found that prolonged physical inactivity increases muscle loss by 6-8 times more than those who lead an active lifestyle.Thus, inactivity results in higher muscle loss than leading an active lifestyle. Furthermore, as we get older, it becomes more difficult to put on muscle mass, or muscular hypertrophy, which is only possible with resistance training.

Studies indicate that in addition to the quantity of protein we consume, the quality of protein and the specific amino acid composition of the protein also play a role in health management and longevity. Dietary protein, especially particular amino acids such as methionine, leucine, and glycine, regulate metabolic health, longevity, and aging. Thus, we need a lot more protein intake in terms of different constituent amino acids than the RDA. Scientists are advising the intake of specific amino acids in order to prevent disease and muscle decline.

Several practitioners are still stuck at recommending the RDAs for macronutrient intake, failing to accommodate age, gender, and activity levels. Look for a practitioner who gauges your individual protein needs as per your current situation. It’s important for us to develop an awareness of moving away from a one-answer-fits-all RDA.

Why is  muscle strength important in the context of longevity?

Muscles serve two major functions in our body: controlling bodily functions such as heartbeat, digestion, and breathing, as well as our functional mobility. 

Lack of functional mobility can have serious implications, such as weak grip, falling, loss of balance, and loss of mobility. Muscle metabolism regulates insulin and blood sugar in the body. Thereby, loss of muscle strength can result in an increased risk of cardiovascular diseases, type 2 diabetes, hypertension, and metabolic syndrome. Low muscle strength is also associated with cognitive impairment and a higher risk of neurodegenerative conditions like Alzheimer’s, dementia, and Parkinson’s. 

Takeaway regarding protein intake, muscle strength and longevity: 

• Dietary protein is an important macronutrient and plays a key role in health and longevity.
• RDA is the minimum amount to keep you away from sickness and maintenance, not the specific amount you need for healthy muscle function and functional longevity.
• Preventing muscle loss is easier than gaining muscle mass.
• The quality of protein you consume has a significant role in determining your muscle function and longevity.
• A diet high in high-quality protein containing specific amino acids such as methionine or branched-chain amino acids has been shown to contribute to healthy aging, improved metabolic function, and decreased muscle wastage.