What Are the Current Recommendations for Daily Protein Intake?
The Food and Nutrition Board of the National Academy of Sciences establishes a healthy dietary range for every nutrient. For protein this healthy range goes from a minimum intake of about 50 grams per day (identified as the RDA) up to about 200 grams per day (identified as an Upper Limit). For food labels, the Food and Drug Administration (FDA) uses the minimum RDA value and recommends that the average person who consumes 2000 calories daily should be getting just 50 grams of protein every day. People often interpret this amount of protein as the maximum intake when it is actually the minimum. The FDA food label is derived from research in the 1960’s and 70’s and the label guidelines have not been updated with the more advanced research during the past 50 years.
For example, Dr. Donald Layman has published over 120 scientific papers on dietary protein and the essential amino acids that make up the protein that we eat every day. None of these studies or those of his colleagues have been taken into account to update the FDA’s food label or typical dietary guidelines for daily protein intake. There are major findings that show the current recommendations for dietary protein are not adequate for adults.
Why Are the Current Protein Recommendations Insufficient?
The current daily protein recommendations were developed from studies in the 1960’s and 70’s designed to determine the minimum amount of protein necessary to prevent deficiencies in healthy, active 20-year-old men. Research has shown that these requirements for young men are significantly lower than the protein needed to maintain optimum health in older adults. Further, these recommendations are based on an old method known as nitrogen-balance that estimates the minimum needs for total protein. This method works okay for children and young adults who are still growing but fails to define needs to maintain health in adults.
Current recommends are insufficient because they do not take into account the unique roles and requirements for each of the building blocks of protein, called amino acids. We do not actually need protein; we require the 20 amino acids that are in the protein. All proteins in food or in your body are made up of these individual amino acids. Protein is simply a food source of these essential amino acids. When we eat protein, the protein is immediately broken down (i.e. digested) to the individual amino acids which are then absorbed into the body. So, protein is similar to a vitamin pill. We don’t need the pill; we need the 12 vitamins inside the pill.
The individual amino acids can then be used to make new proteins in our bodies, or they also play central roles in our everyday bodily functions. Arginine helps regulate blood pressure. Methionine and leucine are integral to the metabolic health of muscle. Lysine helps burn fat and turn it into energy. Tryptophan is essential for regulating nerve function, mood, and sleep. Cysteine is integral in combatting inflammation. Of the 20 amino acids in food, 9 of the amino acids are recognized as essential because we need a constant daily supply of them.
Dr. Layman has done studies that show in order to optimize the functions of the amino acids, the daily intake of these essential amino acids should be higher than the amount provided by the current RDA for total protein.
What Should Your Daily Protein Intake Be?
Based on research focused on optimizing adult health, the daily protein intake for adults should be approximately twice the minimum RDA. Instead of the RDA recommendation of 0.8 grams of protein for every kilogram of body weight (or 0.36 grams of protein per pound of body weight), adults should be consuming within the range of 1.2 to 1.8 grams of protein for every kilogram of body weight (0.55 to 0.82 grams of protein per pound of body weight).
Studies by Dr. Layman showed that with only the minimum amount of protein recommended by the RDA, we are not getting a sufficient amount of essential amino acids to achieve peak metabolic performance of muscles. Healthy muscles are the key to long-term regulations of blood sugar, blood lipids, and our ability to burn body fat.
For example, the RDA requirement for the essential amino acid leucine, which plays an integral role in muscle metabolism, is set at only 2.5 grams per day. While Dr. Layman’s research revealed that the average person should be consuming 3 grams of leucine with every meal – that’s over three times the RDA recommendations! For a better idea of what that looks like, it is important to know how much leucine is in food. Typically, leucine comprises about 8% of the protein you consume. If you consume 100 grams of protein, that protein will contain about 8.0 grams of leucine.
In order to achieve about 3 grams of leucine per meal, you should be consuming a minimum of 30 grams of protein at each meal. That is more than half the RDA minimum recommendation for just one meal.