Determining Protein Intake: A Guide for You
In the realm of nutrition, protein plays a pivotal role in maintaining overall health, building and repairing muscle, and promoting a feeling of fullness. Here's a breakdown of protein requirements, sources, and benefits.
Proteins are made up of amino acids, which link together to create new proteins. The human body produces 11 amino acids, known as non-essential amino acids, while nine amino acids are essential and must be obtained from food.
For a general population, protein intake can significantly influence weight loss and muscle preservation. High protein, calorie-restriction diets have been found to lead to increased weight loss, fat mass loss, and preservation of lean mass compared to low protein diets [1].
The recommended daily allowance (RDA) of protein for adults over 19 is 10-35% of daily calories. However, this RDA is a minimum to prevent deficiency and may not optimize muscle health, especially with aging or physical activity [1][3].
For healthy sedentary adults, the recommended intake is around 0.8 g/kg/day to meet basic nutritional needs [1][3][4]. Active adults and exercisers require a higher intake, with 1.4–2.0 g/kg/day supporting muscle maintenance and repair [1]. Older adults, peri/postmenopausal women, pregnant and lactating women, and those in periods of illness, dieting, or aging with muscle loss may require even higher levels, up to 2.3–3.1 g/kg/day [1].
Animal sources such as chicken, beef, fish, and dairy products are high-quality or complete protein sources. Plant proteins like beans, lentils, and whole grains are incomplete proteins, but still valuable sources of protein. Soy products are high-quality, complete protein sources that derive from soya beans [5].
Eating within 30-60 minutes of finishing exercise may be the most beneficial for building muscle. Including protein as part of a balanced diet can assist with weight loss [6].
However, it's essential to note that high protein diets that are high in fat may put an individual at risk for heart disease, high cholesterol, colon cancer, or other health problems [7]. Eating more than 2g of protein per kg of body weight over a long period may cause digestive, vascular, and renal problems, including kidney stones [8].
Lastly, it's crucial to establish personal protein requirements. Using an online calculator can help people establish their protein requirements based on their age, activity level, and health status [9].
References:
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5014803/ [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6000633/ [3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5694788/ [4] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5775389/ [5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5429537/ [6] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5583738/ [7] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3177870/ [8] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2857475/ [9] https://www.niddk.nih.gov/health-information/nutrition-diet/protein-and-weight-loss/calculate-protein-needs-for-weight-loss
Protein, being a vital macronutrient in the science of nutrition, is essential for maintaining overall health, building muscles, and promoting feelings of fullness. High protein, calorie-restriction diets can lead to increased weight loss and preservation of lean mass compared to low protein diets. It's important to determine personal protein requirements to optimize muscle health, especially for active adults, exercisers, older adults, pregnant and lactating women, and those in periods of illness, dieting, or aging with muscle loss. Animal sources like chicken, beef, fish, and dairy products are high-quality or complete protein sources, while plant proteins like beans, lentils, and whole grains are valuable incomplete sources.
