October 15, 2021

The main goal of many individuals at the gym is weight loss. However, others may be interested in just the opposite. Some may be less interested in weight loss and more interested in weight gain and building muscle. 

Building Muscle Mass

Muscle hypertrophy, or muscle growth, occurs as a result of muscular damage. When we exercise, our muscle fibers are torn. As a result, the body sets out to repair the damage. It does this by fusing torn muscle fibers together to form new muscle protein strands. These new strands are known as myofibrils. The repaired myofibrils increase in thickness and number. This leads to an overall increase in muscle mass and size. 


Muscle growth occurs when the rate of muscle fiber repair is greater than the rate of muscle fiber breakdown. The building of muscle does not occur during exercise. Rather, it takes place during rest and recovery. While our bodies rest and recover, torn muscle fibers are mended resulting in muscle growth. 


Because muscle growth happens during rest and recovery, proper nutrition is critical to building muscle. The food we eat is fuel for our bodies and our muscles. Eating the proper foods provides the body with the nutrients it needs to repair damaged muscle fibers and promote muscle growth. 

Nutrient Profile: Peanut Butter for Muscle Building

Peanut butter is a nutrient-rich whole food that can be a great addition to a muscle-building diet. Check out the benefits peanut butter has to offer and why your clients may benefit from including it in their diet. 


Protein is an extremely important nutrient when it comes to building muscle. Amino acids are the building blocks of protein. They help to repair muscle tissue after exercise. Consuming a protein-rich diet can help promote muscle hypertrophy. Peanut butter contains 8 grams of protein per 2 tablespoons. While peanut butter is not protein-dense in comparison to other whole-food options, it can be a great addition coupled with other high-protein sources such as cottage cheese and whey protein powder.

Monounsaturated Fats

Monounsaturated fat is a healthy fat found in peanut butter. These fats help to develop and maintain cells in the body. Monounsaturated fats such as those found in peanut butter may help reduce levels of LDL cholesterol and lower the risk of heart disease

Vitamins and Minerals

Peanut butter is filled with vitamins and minerals including:


Folate (Vitamin B9)

Folate is a water-soluble B vitamin. It is important in red blood cell formation and is critical for healthy cell growth and function. Folate may also exert positive effects on skeletal muscle development


Vitamin E

Vitamin E is a fat-soluble vitamin that plays a vital role in repairing the plasma membrane of cells. Muscles experience a natural tear and repair process. Vitamin E helps to support this natural process to promote healthy muscle building. Without sufficient Vitamin E, the plasma membrane of muscle cells cannot heal properly and muscle growth will not occur. 



Magnesium is one of the most abundant minerals in the body. It is involved in over 600 cellular reactions. Magnesium acts as a natural calcium blocker and helps the muscles relax. Low magnesium levels may lead to muscle cramps or spasms. Magnesium consumption can aid in your client’s recovery and support their muscle-building goals. 



Zinc is a trace mineral that is not stored by the body and must be consumed through the diet. It is an important mineral that aids in muscle protein synthesis, the process by which protein consumed becomes part of the muscles. Zinc is also vital in supporting the functions of insulin-like growth factor, a hormone released after exercise that promotes muscle growth. 



Iron is an important mineral in the body. Without enough iron, red blood cells can’t carry enough oxygen to the muscles and tissues that need it. Consuming adequate amounts of iron helps provide adequate oxygen to working muscles during exercise. 

The Affordability Factor

Active consumers are bombarded by shelves filled with energy bars, protein powders, and weight gain shakes. And these engineered sports foods are anything but affordable. Consumers interested in muscle building may be purchasing calorically dense meal replacement products or other mass-gaining protein powders. But supplementing with such products can get expensive fast. 


Peanut butter is a healthy alternative. It is calorically dense and relatively inexpensive. One tablespoon of peanut butter provides 100 calories for about $0.07. Peanut butter can be an affordable option for individuals looking to consume more calories throughout the day. 

When Should I Be Eating Peanut Butter?

Including a nutrient-rich food like peanut butter may be a great addition to your client’s diet. It can help them feed their muscles and promote muscle growth. Encourage your clients to add peanut butter to their regular meals and snacks throughout the day. Consider mixing peanut butter into a morning protein shake to kickstart the day or curb afternoon cravings by spreading some peanut butter on a rice cake.


It is good to avoid peanut butter as a pre-workout meal or snack. Peanut butter is high in fat and eating it before a workout can delay digestion. This is because it takes longer for the body to digest fat. Consuming peanut butter before working out may lead to your clients feeling sluggish and slow. 


Peanut butter is also not the best for a post-workout meal or snack. The most important thing after a workout is to refuel the body quickly. Peanut butter’s high fat content causes the body to work overtime to digest everything properly. In addition, it is relatively lower in protein compared to other high protein options like cottage cheese or a protein shake. Post-workout snacks should offer high protein and quickly digestible carbs. 

What Kind of Peanut Butter?

There is no shortage of peanut butter brands and varieties on the shelves today. Not all peanut butters are made the same and not all of them have the same ingredients. Encourage your clients to shop with care when selecting a peanut butter. It is best not to judge based on fat percentage or protein because values are fairly similar across all brands. Instead, your clients should look for natural peanut butter options. 


Natural peanut butters have very few ingredients and most do not contain added sugar. Natural peanut butters use peanuts as the main ingredient with some added oils and salt for taste. Commercial peanut butters often have various oils added to decrease production costs. Added sugar is also found in commercial peanut butters to enhance taste. 


Natural peanut butter has a slightly different taste than the commercial peanut butter most consumers are used to. It may take some time for your clients to find a brand and flavor they like. But switching to a natural peanut butter is a healthier option overall. 


If you have clients who want to enjoy the taste of peanut butter without the extra calories, powdered peanut butter is a great option. Powdered peanut butter is newer to the scene but provides the same nutrients as peanut butter without the additional unwanted calories. 

Peanut Butter: A Muscle-Building Food

Peanut butter provides protein, monounsaturated fats, several vitamins and minerals, and won’t break the bank. Including a nutrient-rich food like peanut butter may be just the addition your clients need.


Interested in learning more about how nutrition can support muscle building and affect overall athletic performance? Check out ISSA’s Nutritionist course. Help clients uncover why they eat the way they do and how they can build healthy eating habits to support their fitness goals!



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