5 Protein Myths You Should Know

Written by: Rocío Rivera-Ortega, MS, RD, LND & Tatiana Velez, MS, RD, LND, CPT

Co-author: Nancelys M. Rodriguez

Assortment of green vegetables such as peas, asparagus, and lettuce on a wooden table.

Interest in wellness and physical activity has become increasingly important in Puerto Rican society as people aim to maintain good health and improve body composition. As a result, protein consumption has increased as support for fitness goals.

Protein is an essential component of the body that plays important roles in tissues and organs. It is consumed through the diet from both animal and plant sources.

Some foods that contain protein include white and red meats, fish, dairy products, soy products, and legumes.

Do you know how much protein you should consume per day? Should you drink protein shakes every day? Should you only consume protein to increase muscle mass?

If you participate in physical activity or high-performance sports, this information can guide you toward better nutrition and performance.

Below, common statements and questions about protein will be discussed.

Why is protein important for health?

Among its primary functions, protein helps support joints, sends signals that regulate many cellular processes, contributes to immune system responses, and transports other molecules throughout the body.

In addition, protein intake is associated with muscle mass and muscle growth, both in sports performance and overall health throughout all stages of life.

Protein consumption is essential for muscle growth, especially for individuals involved in high-performance sports.

According to an article published by Beaudry et al. in 2022, approximately 30% and 38% of body composition corresponds to protein in women and men, respectively.

In this article, Fuel Labs discusses five myths about protein within the wellness and fitness space in Puerto Rican society.

Using scientific evidence as a foundation, these statements are evaluated while emphasizing the importance of individualizing protein intake and supplementation according to each person’s needs and physical activity or sport.

Myth 1: Everyone who goes to the gym or exercises should take protein supplements to gain muscle mass

When we go to a gym, it is common to see a protein shake station, leading many people to consume them regularly. It is often assumed that protein intake must increase immediately after workouts.

However, before determining whether protein shakes are necessary, it is important to evaluate total daily protein intake and the type of training being performed.

According to the Academy of Nutrition and Dietetics, the daily protein recommendation for physically active individuals and athletes ranges from 1.2 to 2.0 grams per kilogram of body weight per day. Therefore, before supplementing with protein, it is extremely important to evaluate dietary intake to determine whether additional protein or supplementation is actually needed.

When daily protein intake is assessed, most individuals are already meeting their protein needs through food alone and do not necessarily need protein shakes or supplements. Scientific studies also show that consuming more than 2.2 g per kilogram of body weight does not result in greater muscle gain.

However, for high-performance athletes and strength sports athletes, protein requirements may be higher. If an athlete cannot meet their nutritional needs through food alone, protein supplementation may be appropriate.

To properly analyze protein supplements available on the market, determine individualized amounts, and evaluate frequency of use, consulting with a registered nutritionist-dietitian is recommended.

Myth 2: The solution for weight loss or better performance is eating more protein

When people set weight-loss goals, it is common to eliminate fats and carbohydrates while significantly increasing protein intake throughout the day. However, although protein helps preserve muscle mass during weight loss, consuming excessive amounts of protein does not automatically result in weight loss or increased muscle mass.

Daily protein intake should not exceed 35% of total daily calories. Carbohydrates and fats remain extremely important when trying to build muscle and lose weight because they help maintain energy balance and proper organ function.

Additionally, studies demonstrate that consuming carbohydrates and protein together after exercise supports muscle recovery, which is especially important during muscle-building phases (Margolis, 2021).

Myth 3: If I consume excess protein, I eliminate it through urine

Several scientific articles show that healthy kidneys can adapt to protein consumption in the diet. However, individuals with kidney disease or kidney-related conditions may experience complications, including protein excretion in the urine.

Healthy kidneys do not eliminate essential nutrients or excess protein simply because more than 30 grams are consumed per meal, despite general recommendations from Mayo Clinic suggesting 15–30 g per meal.

This demonstrates that if a high-performance athlete requires more than 30 grams of protein per meal to maintain performance and improve recovery based on their sport, there should not be increased risk if kidney function is healthy.

Myth 4: Only meat is a good source of protein

Culturally, many people grow up believing protein only comes from meat, fish, and chicken. In Puerto Rican culture, it is common to hear that “a meal is not complete without a piece of meat on the plate.”

In addition to animal protein sources, there are also plant-based protein sources that come from plants.

Plant protein sources include legumes such as lentils, beans, and chickpeas. Other plant-based protein foods include tofu, edamame, quinoa, soy, chia seeds, nuts, and whole grains.

According to data from the United States Department of Agriculture (USDA), these foods provide the following amounts of protein:

½ cup tofu: 21.76 g
1 cup canned pinto beans: 13.13 g
1 cup medium-grain white rice: 4.43 g
1 cup cooked soybeans: 7.96 g
1 serving (6 oz) plain yogurt: 5.9 g

These foods provide additional ways to meet daily protein recommendations while incorporating high-fiber plant foods that support bodily function during physical activity.

Myth 5: You cannot get enough protein from plant sources alone

As interest in wellness increases, plant-based diets have become more common. This may be due to personal beliefs, environmental concerns, medical conditions, or other personal reasons.

One concern regarding plant-based eating is the belief that plant proteins do not provide enough nutrients to support all bodily functions.

However, to achieve adequate protein intake, plant foods can be combined strategically to provide all essential amino acids.

Amino acids are the building blocks of protein. Essential amino acids must be consumed through the diet because the body cannot produce them on its own.

One example of proper protein complementation is a meal containing rice and beans, which together provide all essential amino acids.

According to a scientific study published in 2021 by Craig and colleagues, consuming a plant-based diet can provide adequate protein intake when a variety of foods are consumed throughout the day.

The same article also shows that athletes can meet nutritional recommendations necessary to support high-performance training while consuming plant-based protein sources.

Scientific literature establishes that plant proteins provide essential amino acids but require attention to vitamin B12, vitamin D, iron, and calcium levels (Marsh, 2013).

Consulting with a registered nutritionist-dietitian is recommended if you wish to follow a plant-based diet to ensure all nutritional requirements are met.

In summary

Protein is an essential nutrient and should be included in all meals throughout the day to maintain proper health, especially musculoskeletal health. Both animal and plant protein sources can help meet nutritional recommendations.

For individuals participating in high-performance training, understanding individualized protein requirements is important for maintaining optimal levels.

This review demonstrates that increasing protein intake can support weight loss and muscle gain goals; however, it does not necessarily mean supplementation is required.

It is equally important to maintain balance with the other primary nutrients—carbohydrates and healthy fats—to support proper bodily function.

In conclusion, excessive protein intake does not automatically lead to greater muscle gain, and before following wellness trends, it is important to evaluate information sources and consult qualified healthcare professionals.

ReferencES

Beaudry KM, Binet ER, Collao N and De Lisio M (2022) Nutritional Regulation of Muscle Stem Cells in Exercise and Disease: The Role of Protein and Amino Acid Dietary Supplementation. Front. Physiol. 13:915390.

Craig, W.J.; Mangels, A.R.; Fresán, U.; Marsh, K.; Miles, F.L.; Saunders, A.V.; Haddad, E.H.; Heskey, C.E.; Johnston, P.; Larson-Meyer, E.; et al. The Safe and Effective Use of Plant-Based Diets with Guidelines for Health Professionals. Nutrients 2021, 13, 4144.

Marsh, K. A., Munn, E. A., & Baines, S. K. (2013). Protein and vegetarian diets. Medical Journal of Australia, 199(S4).