Protein is one of the most underappreciated macronutrients that I see day in and day out in my profession as a personal trainer and nutrition coach. 

A macronutrient that has the power to change body composition, satiety, muscle mass, bone health, metabolism, immune function, hormone function, cognitive affects, energy, recovery and more.

MUSCLE MASS

Are you looking to build muscle or maintain muscle with age?

Protein intake plays a key role in your desired outcome. Whether you are looking to build muscle mass for esthetic reasons or to maintain muscle to help the aging process, protein is a macronutrient you need daily. Protein is the building block of muscles. 

Individualized daily protein intake paired with resistance training will help with the goal of building muscle mass and changing body composition when paired with a few other variables.

Robert R. Wolfe, a Ph.D. and Professor of Geriatrics at Donald W. Reynolds Institute on Aging found through his research that, “dietary protein is critical for the maintenance of optimal health in normal growth and aging. If all other variables are controlled, increased muscle protein synthesis leads to improved muscle mass, strength and function over time. Increased muscle mass, strength and function are related to improved health outcomes.”

To maintain muscle mass and slow the decline of muscle degeneration (a part of the aging process called Sarcopenia), ensure you are getting your adequate daily protein intake. When paired with resistance training, it can help you keep your muscle or dramatically slow the muscle degeneration process that can start as early as 25 years of age.

HORMONES AND OUR CENTRAL NERVOUS SYSTEM

Our central nervous system and hormones require a number of amino acids found in protein foods.

Amino acids are required by all living things and play a number a crucial roles in our bodies. Our bodies do not make all amino acids naturally. There are 20 different amino acids in total, nine of which are essential to our survival and can only be found through our foods.

The best sources of amino acids are found in animal proteins. 

Harris R. Lieberman, a renowned Research Psychologist at U.S. Army Research Institute of Environmental, concluded through research that, “amino acids are used by the brain for the synthesis of various neurotransmitters and neuromodulators.”

Paola Bellosta, PhD, an Adjunct Associate Professor in the Department of Medicine at NYU Grossman School of Medicine, found through her research that, “peptide hormones, which have an effect on the endocrine system, play a prominent role in controlling energy homeostasis and metabolism.”

Amino acids have been implicated in controlling appetite, the function of the gastrointestinal and cardiovascular systems, energy expenditure, reproduction, the growth and repair of body tissue, maintain healthy skin, hair and nails.

WOUND RECOVERY

Wound healing is completed by a four stage process. Each process is imperative to the success of the wounds recovery. Your overall nutrition will play a large role in how well this process takes place, however protein plays a very important role and it can not be completed without it.

Studies in 1985, 2003 and 2006 conclude that, “a deficiency of protein can impair capillary formation, fibroblast proliferation, proteoglycan synthesis, collagen synthesis, and wound remodeling. A deficiency of protein also affects the immune system.”

ENERGY BALANCE, SATIETY, AND WEIGHT LOSS

They are all linked with a good nutrition regimen that is designed around your personal health targets.

When you add a focus on dietary protein intake and complex carbohydrates you will notice an increase in satiety (the feeling of having a satisfied appetite).

Due to the foods you are eating they have an affect on how fast you feel hungry again and or dictate to what you may crave next. When you eat a nutrition regime higher in good quality proteins and high fiber foods, the lasting feeling of being full is increased by what’s known as diet-induced thermogenesis.

Thermogenesis is the thermic effect of food. This is defined as the production of heat. This reaction takes place because your body has to work hard to digest these foods.

This process increases the amount of energy it takes for your body to digest, absorb and metabolize your food therefore increases the metabolic effect. Because your body creates more heat when digesting these foods and they are slower for your stomach to digest they burn more calories. It is a way of burning more calories without exercise.

If you are full longer you are binge eating less often which often leads to weight loss or body re-composition. Your body will sustain better energy as the food digesting slower it provides you with nutrients being up taken by the body longer therefore increasing your energy expenditure for longer periods of time.

If you’ve ever eaten only a donut, you will notice you are hungry fast, craving more sugar and you feel tired after about thirty minutes as you come down from the sugar rush. A good quality meal will provide you with a different outcome.

OSTEOPOROSIS

Osteoporosis is a loss of bone from a lack of protein intake (learn more about it at Osteoporosis: The Silent Thief). Approximately 50% of your bone is made up of protein.

One of many studies on the topic had 615 participants with a age range of 68-91 years of age. Protein intake varied depending on the age, weight, height of the individual. Lower protein intake was significantly related to bone loss at femoral and spine sites.

Protein intake with an adequate recommended daily intake based on individualized factors of the person has been proven in many studies to slow bone loss or delay the onset of it.

LOWERING BLOOD PRESSURE

In 2005, a two year study was completed using a variety of nutrition regimens to test the outcomes of lowering blood pressure. 

Once completed the authors concluded that when “compared with the carbohydrate diet, both the protein and unsaturated fat diets significantly lowered systolic and diastolic blood pressure in all participant.”

As well, “in prehypertensive participants, the protein and the unsaturated fat diets each lowered blood pressure similarly, but blood pressure reductions were statistically significant only for the protein diet.”  “

They concluded that, “in the setting of recommended levels of saturated fat, cholesterol, fiber, fruit, vegetables, and minerals, diets that partially replace carbohydrates with protein or monounsaturated fat can further lower blood pressure, improve lipid risk factors, and reduce Cardiovascular disease risk.”

Food is medicine and can help you take back some control of your blood pressure while working with your medical professional.  Medicine serves a purpose but for those individuals believing their is zero hope to help lower your blood pressure, please don’t give up.

HOW MUCH PROTEIN?

On average, the recommended daily intake is 0.8 grams of protein per kilogram of body mass per day.

Many studies have stated that to maximize protein intake, the recommended amount is 1.6 g per kg per day to 2.2 g/kg/day or converted into pounds, 0.7 g per 1lb per day to 1g per 1lb per day.

These recommendations are based on many factors, including age, height, weight, activity levels, and body composition targets. 

Older adults and elite athletes may require more protein than others. If you are currently carrying a lot of access body fat it is recommended to use one gram of protein per centimeter in height.

Many wonder if they have to have their recommended daily protein intake at specific times of the day or can they eat it all in one meal?

At one time it was thought to have to eat protein within 30 minutes post workout in order to get the benefits for muscle gain. That has been proven not to be the case.

Getting your protein in over the course of your day is what the primary target is. For energy balance you may consider spacing protein containing meals every three to five hours throughout the day. 

This is to maximize muscle protein synthesis rates over the course of a 12-hour period. It is recommended to take in protein one to three hours prior to sleep to offset the declines in muscle protein synthesis that may occur during an overnight fasting period.

To maximize muscle protein it is best paired with resistance exercise. Spacing protein for reasons such as energy, satiety, cognitive benefits, consumption factors based on the amount g/kg/day you may require over the course of a 24 hour period.

Many studies conclude that high protein diets are not hazardous for the healthy kidneys. If you have a kidney problem, do not increase your protein without speaking to your medical advisor.

REFERENCES

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