Protein is a key part of any diet, with experts even arguing that it is the most important part of a meal. While the importance of protein in any diet is not up for debate, there’s a lot of controversy about how much protein we actually need. Although there’s a standard RDA for protein, recent studies show that the body needs much more protein. This article will examine how much protein the body actually needs and the best practices for incorporating plant and animal protein into your diet.
Protein is the primary building block of the body. It is necessary for making muscles, skin, bones, and organs, as well as enzymes, neurotransmitters, hormones, and other essential molecules in the body.
It is fair to say that the body cannot survive without protein, as it is responsible for the growth and repair of body cells. Enzymes, made from proteins, are also critical in virtually all body processes. Besides its biological processes, extra protein is useful in weight loss, weight gain, and strength training routines.
Recommended Dietary Allowance (RDA) is the estimated amount of a nutrient per day considered sufficient to meet the requirements of about 98 percent of healthy individuals in a group. In other words, the RDA is the adequate intake amount of a particular nutrient.
The RDA for protein is 0.8 grams per kg (0.8g/kg/d) of body weight. According to the CDC, the average American male weighs 90.6kg (or 200lbs), while the average American female weighs 77.5kg (or 170 lbs). This corresponds to a recommended 72 grams of protein daily for men and 62 grams for women in the United States.
While the Recommended Dietary Allowance suggests the term refers to the adequate amount of a nutrient to be taken daily, the term is misleading. In reality, the RDA for a nutrient is the minimum amount of that nutrient a person needs to survive, and not the optimal level required for good health.
For instance, the RDA for protein is 0.8g/kg, as determined by nitrogen balance studies, but that is only the amount required to avoid deficiency. The amount of protein required to maximize muscle mass, strength, and maintain good health is significantly higher.
Starvation studies even show that grossly depleted individuals could still maintain nitrogen balance until a few moments before their death. Consuming just the RDA for macronutrients, including protein, would only meet 40 percent of the total energy requirement. This implies that although the RDA for protein may be sufficient to keep an active body functioning, it is not enough for maximizing health.
The RDA protein is not the optimal protein intake level; instead, it is the minimum level the body requires to function normally. To get the optimal protein intake level, we need to consider the Acceptable Macronutrient Distribution Range (AMDR) specified by the Dietary Guidelines for Americans.
The AMDR considers numerous macronutrients the body needs, and it is recommended that adults get 10 to 35 percent of their total caloric intake from proteins.
Using the weight and height specifications of an average, physically active 20-year-old American man, the estimated daily caloric need is 3458 kcal. Ten percent of that caloric need is 346 calories, while 35 percent is 1210 calories. Since one gram of protein yields four calories, the man approximately requires between 87 and 303 grams of protein daily. That translates to between 0.96g/kg/d and 3.34g/kg/d (or grams of protein per kilogram of weight per day) to meet 10 to 35 percent of total caloric intake.
This calculation shows that the adequate protein intake is indeed higher than the RDA for protein for that man. You can do a similar calculation online using AMDR guidelines to get an appropriate reflection of how much protein you need daily.
Not everyone needs the same amount of protein. Many factors affect the optimal daily protein intake, including age, muscle mass, sex, activity level, overall health, and pregnancy and lactation status. Below are classes of people who may need more protein.
Children’s bodies are constantly growing. Given that protein is the major component required for the growth and development of cells and muscles, children need more protein proportional to their body weight than adults.
After the age of 30, muscle mass decreases approximately three to eight percent per decade. The progressive loss of muscle, also called sarcopenia, occurs at an even faster rate after the age of 60, largely due to the more sedentary lifestyle of older adults. Therefore, the elderly need to get more protein to preserve weight mass.
While the normal RDA for protein is 0.8g/kg, older adults need 1 to 1.2 grams of protein per kilogram of body weight. One study showed that elderly people with a protein intake of 1.2g/kg recorded improvements in their physical performance and muscle mass.
Protein is critical for the development of fetal tissues and organs. It also aids the growth of breast and uterine tissue in pregnant women. In addition, during lactation, women need to consume more protein to maintain their own muscle mass while supplying their babies with adequate nutrition through breast milk. Experts even state that breastfeeding mothers may need as much as two times more protein than non-nursing women, which would work out to 1.6g/kg.
The more physically active a person is, the more calories they need to consume daily. Since athletes usually undergo intense physical exercise and training, they have a higher RDA for protein. According to one study, athletes can consume up to 3.5 grams of protein per kilogram of body weight.
Protein can help in losing weight. That may seem strange and contradictory, considering protein is the major dietary component for muscle gain. However, studies show that protein can increase metabolic rate and reduce appetite, helping to burn present calories and limit calorie intake. For weight loss, the RDA for protein should be between 1.6 and 2.4 grams per kilogram of body weight.
Also, if your diet targets weight gain or muscle building, you need a higher protein intake than the RDA. However, taking more protein alone is not enough for proper muscle building, and it has to be coupled with exercise for the best results.
Protein plays a significant role in rebuilding and repairing the body. As such, people recovering from an injury need to consume more protein than the normal RDA for protein. Aside from injuries, some medical conditions may require increased protein intake. One such medical condition is Adrenal Fatigue (AF).
Adrenal fatigue occurs when the body cannot cope with chronic life stressors and can seriously affect the quality of life. Naturally, the body has an in-built stress-coping mechanism known as the NeuroEndoMetabolic (NEM) Stress Response.
The NEM comprises six circuits of organs and systems that work together to face stress. If the body is consistently weak from a chronic medical condition or injury and protein is inadequate in the body, the Bioenergetics circuit of the NEM may dysregulate. If this persists, Adrenal Fatigue may arise.
Fortunately, one of the primary steps to managing Adrenal Fatigue is diet. An adrenal fatigue diet comprises about 20 to 30 percent animal protein and 10 to 20 percent legumes and beans, which are plant proteins. This is consistent with the recommended 10 to 35 percent of total caloric intake from protein.
Dietary protein can come from either animals or plants. The main difference between the two types of protein is their amino acid content.
Protein itself is made of amino acids. There are 20 different types of amino acids, but the body can only produce 11 of these. The other nine amino acids must be obtained from the diet and are considered essential amino acids.
Animal proteins are often regarded as complete proteins because they contain all nine essential amino acids. On the other hand, plant proteins are known as incomplete proteins because they typically lack at least one essential amino acid. Still, some plants, like soybeans and pea protein, contain all essential amino acids. Complementary plant protein sources can also be paired in the diet to make complete proteins.
Considering that animal protein generally is more complete than plant protein, in terms of amino acids, many see it as better. But while that view is understandable, it is not that simple, as plant proteins can be made “complete” by combining them. Simply, you can eat complementing plants to make sure you are getting all of the essential amino acids.
When choosing between the two, it is more consequential to consider the other nutrients that accompany the protein sources. For instance, red meats, particularly processed ones, contain all the essential amino acids, but studies have linked them to cardiovascular conditions because of they raise cholesterol. Interestingly, studies link plant protein to reducing risk factors for cardiovascular conditions.
Also, plant protein sources contain fiber which promotes the feeling of fullness and reduces overeating, making it important in weight loss.
Both plant and animal proteins have their benefits and shortcomings, and the best resolution is to incorporate a variety of these proteins into the diet.
Besides the RDA for proteins, there is also controversy on the effects, if any, of the patterns of protein intake (protein distribution) in a day. Basically, some experts believe that protein intake should be distributed evenly across all meals of the day as opposed to a skewed distribution, where the bulk of protein intake comes in just one meal. The skewed protein distribution is more typical for Americans, with the lowest intake at breakfast and the highest at dinner.
There have been conflicting studies on this topic. Some studies support an even protein distribution, as consuming the bulk of protein at one time is seen as a “waste” because the body oxidizes excess amino acids. However, other studies show that there’s no difference in protein synthesis in both even and skewed protein distribution diets. More studies are needed to confirm if one of these protein intake patterns is actually better, but for now, all that matters is getting an adequate amount of protein daily.
Still, for some conditions, like Adrenal Fatigue, a protein-rich breakfast as soon as possible after waking is essential. This contradicts the common American pattern of concentrating on protein intake during dinner and taking the least amount of protein during breakfast. Therefore, people managing Adrenal Fatigue or under high stress should favor an even protein distribution or even skewed distribution but with breakfast constituting the bulk of protein intake.
Since there are so many protein sources, it is markedly easier to incorporate protein into your diet than many specific vitamins and minerals. Below are some tips that will guide you on how best to meet or exceed the RDA for protein.
In a meal containing various components, eat proteins first. This prevents overeating, as protein helps stimulate fullness. Also, proteins help regulate blood sugar and insulin levels while eating.
Plant proteins typically lack one or more essential amino acids. However, you can overcome this obstacle by combining various plant proteins into your diet. This also makes it easier to have proteins in all meals as the possibilities are endless.
Protein supplements are common among athletes and bodybuilders, but you can also take them if you consistently fall short of your daily protein intake. Ensure you speak to your health expert before taking any supplements, though.
One of the best ways to incorporate protein into your diet is by consuming snacks high in protein. So, instead of chips and crackers, which offer low amounts of protein, you could snack on cheese, yogurt, nuts, jerky, and other protein-rich snacks.
The RDA for protein is the estimated amount of protein per day considered sufficient to meet the protein requirements of most people, and it is 0.8 grams per kilogram of body weight. However, that is only the minimum level to avoid deficiency, and you need more to reach adequate amounts of protein required for good health. Other sources suggest you may need up to about 3.5 grams per kilo of body weight if you have other health needs or exercise frequently. Fortunately, there is protein in many foods, and there are many options for increasing your intake.
For more information about the optimal diet for your body's needs, the team at Dr. Lam Coaching can help. We offer a free, no-obligation phone consultation at +1 (626) 571-1234 where we will privately discuss your concerns and various options. You can also send us a question through our Ask The Doctor system by clicking here.
Both protein types have their advantages and downsides. Unlike plants, animal proteins contain all essential amino acids; however, some animal proteins have been linked to cardiovascular conditions. Plant proteins, on the other hand, can reduce the risk of these conditions. Regardless, combining both in diet is the best approach.
