Overview
What is it?
Peanut protein is a plant-based protein derived from peanuts, a type of legume that grows underground . It is a naturally occurring protein source found in whole peanuts, peanut butter, and various peanut-derived products like peanut flour and peanut protein supplements . Peanut protein contains all the essential amino acids required by the human body, though it is relatively low in methionine and threonine compared to animal proteins .
How does it work?
Peanut protein provides the body with amino acids, which are the building blocks of protein . When consumed, peanut protein is broken down into its constituent amino acids during digestion. These amino acids are then absorbed into the bloodstream and transported to various tissues, including muscles . In muscles, these amino acids are used to support muscle protein synthesis (MyoPS), the process of building and repairing muscle tissue . This is particularly important after resistance training, as exercise creates small tears in muscle fibers that need to be repaired for muscle growth .
What are the benefits?
Peanut protein offers several potential benefits, especially when combined with resistance training. It may enhance muscle hypertrophy, which is the increase in muscle size, particularly in older adults . Studies suggest that peanut protein supplementation can lead to increased muscle thickness and strength, such as improved knee flexion torque . Additionally, peanut protein serves as a sustainable, plant-based alternative to animal proteins, aligning with dietary preferences for more plant-forward eating patterns . Peanut oligopeptides (POPs), derived from peanut protein, have been shown to improve antioxidant capacity, regulate energy metabolism, and enhance mitochondrial function in mice, potentially delaying fatigue and improving endurance .
Effectiveness
What does the research say?
Research on peanut protein's effectiveness for building muscle mass has yielded mixed results. One study found that peanut protein supplementation, combined with resistance training, significantly increased vastus lateralis (a thigh muscle) thickness and knee flexion torque in older adults, suggesting it may support muscle hypertrophy and strength gains in this population . However, another study involving younger adults found that peanut protein supplementation did not significantly enhance resistance training adaptations compared to a control group . While the younger adult study did not show significant improvements, there were trends suggesting potential benefits for females in lean tissue mass and vastus lateralis thickness . These findings indicate that the effectiveness of peanut protein for building muscle may vary depending on factors like age and potentially sex. Also, one study showed that peanut protein caused a deficit in contractile properties in soleus in rats .
Side Effects
Allergic reactions
Peanuts are a common allergen, and individuals with peanut allergies should strictly avoid peanut protein . Allergic reactions can range from mild symptoms like hives and itching to severe, life-threatening anaphylaxis, which requires immediate medical attention .
Weight gain
While peanut protein itself is not inherently fattening, overconsumption of peanut products, especially those high in fat and calories like peanut butter, can contribute to weight gain if not balanced with overall calorie intake and expenditure . It's important to consume peanut protein as part of a balanced diet and be mindful of portion sizes.
Evidence
Clinical Studies & Trials
[1] Mechanisms of mechanical overload-induced skeletal muscle hypertrophy: current understanding and future directions.
This review discusses the mechanisms underlying muscle growth in response to mechanical overload, such as resistance training. It highlights the role of mTORC1 signaling, ribosome biogenesis, satellite cell activation, and muscle protein synthesis in muscle hypertrophy.
View study[2] Common questions and misconceptions about protein supplementation: what does the scientific evidence really show?
This review addresses common questions and misconceptions about protein supplementation. It notes that peanut butter is often marketed as a good protein source but contains lower protein content per serving compared to lean meat or low-fat dairy products.
View study[3] Immediate Hypersensitivity Reactions (Archived)
This article discusses hypersensitivity reactions, which are exaggerated or inappropriate immune responses to antigens or allergens. It classifies these reactions into four types, with types I, II, and III being immediate reactions mediated by antibodies.
View study[4] The Effects of Peanut Oligopeptides on Exercise-Induced Fatigue in Mice and Its Underlying Mechanism.
This study investigated the effects of peanut oligopeptides (POPs) on exercise-induced fatigue in mice. The results showed that POPs improved antioxidant capacity, regulated energy metabolism, and enhanced mitochondrial function, thereby delaying fatigue and improving endurance.
View study[5] Effect of dietary incorporation of peanut and linseed meals with or without enzyme mixture on physiological performance of broilers.
This study evaluated the effects of peanut meal (PNM) in broiler diets. It found that PNM can substitute corn and soybean meal, reducing feed costs. While PNM did not significantly affect body weight or carcass parts, combining it with linseed meal and enzymes improved nutrient digestibility.
View study[6] Peanut protein reduces body protein mass and alters skeletal muscle contractile properties and lipid metabolism in rats.
This study compared the effects of peanut protein (PP) with casein and cod protein on body composition and muscle properties in rats. It found that PP reduced body weight gain, body protein mass, soleus muscle mass, and liver weight compared to the other proteins. PP also impaired contractile properties in the soleus muscle and increased plasma cholesterol and body fat mass.
View study[7] Effects of Peanut Protein Supplementation on Resistance Training Adaptations in Younger Adults.
This study examined the effects of peanut protein supplementation on resistance training adaptations in younger adults. It found that peanut protein supplementation did not significantly enhance adaptations compared to a control group, although trends suggested potential benefits for females in lean tissue mass and vastus lateralis thickness.
View study[8] The effects of resistance training with or without peanut protein supplementation on skeletal muscle and strength adaptations in older individuals
This study investigated the effects of peanut protein supplementation combined with resistance training in older adults. It found that peanut protein supplementation significantly increased vastus lateralis thickness and knee flexion torque, suggesting it may support muscle hypertrophy and strength gains in this population.
View study