4 Best Natural Bodybuilding Supplements for Building Muscle

Whether you're a competitive bodybuilder hoping to enter a natural bodybuilding competition or simply a fan of the sport, keep reading. Below, we share what natural bodybuilding is, which supplements are banned, and which supplements are safe to take as a natural bodybuilder. 

What Is Natural Bodybuilding?

Some natural bodybuilders claim taking a creatine supplement or pre-workout powder isn't natural. However, it’s tough to argue that taking something you readily consume through food or that your body produces naturally does not qualify as “natural.” If that were the case, you could also argue that eating food containing creatine and glutamine (e.g., red meat) disqualifies you from natural bodybuilding. Pretty silly, right?

The more appropriate definition of “natural bodybuilding” is refraining from using any substance banned by natural bodybuilding organizations. As such, natural bodybuilding competitions only allow competitors who do not use performance-enhancing drugs (PEDs), including but not limited to:

• Anabolic steroids (e.g. trenbolone acetate)

• Growth hormone and peptides

• Selective androgen receptor modulators (SARMs)

• Any controlled substance that is known to augment lean muscle mass gains and/or fat loss. 

Therefore, natural bodybuilders rely exclusively on their diet, training, and dietary supplements—which must contain ingredients allowed by the World Anti-Doping Agency (WADA)—to achieve peak physical condition.

Natural bodybuilders should always consult with the organization they plan to compete in about which nutritional supplement(s) are okay to use, as the list of banned supplements by the WADA may differ slightly.

How Do You Compete as a Natural Bodybuilder?

Natural bodybuilding is different from other types of bodybuilding competitions. The list of banned substances is much more stringent, and you'll often be subject to both urine and polygraph tests (especially if you place high in a competition).

Like all bodybuilding competitions, how you prepare depends on the show you enter. For example, the World Natural Bodybuilding Federation (WNBF or INBF) requires athletes to undergo polygraph testing, urine drug testing, and a contingent follow-up urine drug test immediately after the competition if they win an award. 

In addition, the WNBF requires athletes to be drug-free for 10 years prior to a competition. In other words, former steroid users would need to wait a decade before being eligible to compete in a WNBF competition. 

On the contrary, the International Federation of Bodybuilding and Fitness (IFBB) and the National Physique Committee (NPC) host bodybuilding competitions that are quite permissive about what supplements the athletes can take.

Banned Substances in Natural Bodybuilding Competitions

We cannot stress this enough: The list of banned substances will vary depending on the competition you enter and which organization is sanctioning it.

For simplicity purposes, we will focus on the WNBF's banned substances list, as it’s often recognized as the strictest natural bodybuilding organization in the industry. Therefore, if you adhere to their guidelines, you will likely be within the limits set forth by other natural bodybuilding competitions.

There are roughly 200 substances currently banned from WNBF competitions, including: 

• All anabolic steroids: Notable examples are androstenediol, trenbolone, nandrolone (deca-durabolin), mesterolone, boldenone, drostanolone, and stanozolol (Winstrol).

  • Testosterone: Testosterone is banned In almost all forms, including creams, gels, patches, and injections. The testosterone/epitestosterone (T/E) ratio measures excess testosterone in the body. If your ratio is higher than six to one (the same ratio used by the NCAA), it's listed as a failed drug test.

• Growth hormones/Growth Factors/Peptides: Human growth hormone (HGH), insulin-like growth factor-1 (IGF-1), erythropoietin (EPO), and human chorionic gonadotropin (HCG) are banned, as are most “designer” peptides.

• All steroid hormone precursors/prohormones: Hormone precursors and prohormones.

• All prescription diuretics: Diuretics help rid the body of salt and water weight. Even if they're doctor-prescribed, they're still banned.

• Ephedrine, ephedra, and most stimulants: Caffeine and its derivatives (e.g. theobromine) are fine, but many other stimulants like amphetamine and methylphenidate are banned. Be sure to check your pre-workout powder label so you don’t incidentally consume a banned stimulant.

• Cannabinoids (including CBD), hallucinogens, and opioids: Even legal (CBD) substances are banned, so be careful if you’ve been taking CBD oil. 

The 5 Best Natural Bodybuilding Supplements

As a competitive natural bodybuilder, the goal is to increase lean mass/muscle gains and cut body fat, primarily through diet and resistance training. Natural supplements can help as an adjunct to get you in tip-top shape for your bodybuilding shows.

In fact, competitive lifters and bodybuilders agree it's nearly impossible to win first place at a natural bodybuilding competition without using supplements. Whether you're competing for Mr. Natural Olympia or at a regional WNBF contest, you'll be happy to know the following supplements are allowed (and effective):

1. Creatine Monohydrate

Creatine is an amino acid-like molecule found naturally in many cells (especially skeletal muscle cells). It plays a pivotal role in muscle bioenergetics by replenishing adenosine triphosphate (ATP). In fact, creatine monohydrate is the single most-studied sports supplement, and research results consistently demonstrate its efficacy for improving athletic performance, increasing muscle mass, reducing fatigue during training, and more [1, 2].

Creatine (monohydrate) is also considered one of the safest sports supplements on the market. According to a recent research review by the International Society of Sports Nutrition, creatine is not only safe but can also prevent exercise-related injuries [3].

In addition, there is no scientific evidence that short—or long-term use of creatine causes negative side effects in active adults. You might urinate a bit more, but that just means the creatine is working since it helps pull water into muscle tissue. 

2. Whey Protein Isolate

Whey is a complete protein derived from milk, meaning it contains all nine essential amino acids—the "building blocks" of protein that our body can't produce on its own. Given that natural bodybuilders generally require a generous amount of protein, whey protein powder is a worthwhile investment.

While lean meat is rich in protein, whey protein isolate is easily digestible and rapidly absorbed, making it ideal for stimulating muscle protein synthesis after working out. It is one of the most practical and effective supplements for active individuals, especially those looking to build muscle and preserve lean mass during fat-loss phases [4]. 

In addition, whey protein has been scientifically shown to stimulate muscle growth more effectively than other protein powders, such as soy [5]. Supplement brands are also increasingly focusing on enhancing the flavor profiles and textures of protein powders, recognizing that taste is a key factor in consumer satisfaction and preference.

Transparent Labs 100% Grass-Fed Whey Protein Isolate helps natural bodybuilders get enough protein with delicious natural flavoring and no artificial sweeteners. Alternatively, a plant protein powder like Transparent Labs Organic Vegan is ideal for plant-based bodybuilders.

3. Branched-Chain Amino Acids (BCAAs) and Essential Amino Acids (EAAs)

Essential amino acids (EAAs) are a group of nine amino acids that we must consume for proper biological function and protein synthesis. Any "complete" protein source contains a sufficient balance of all nine essential amino acids. 

BCAAs are a subset of three EAAs—L-leucine, L-isoleucine, and L-valine—considered "master regulators" of muscle protein synthesis [6]. Hence, EAAs and BCAAs have become popular supplements for active individuals and natural bodybuilders looking to improve recovery and maintain/increase muscle mass [7].

Beyond promoting muscle protein synthesis, EAAs and BCAAs can attenuate muscle protein breakdown (MPB)[8]. As such, supplementing with BCAAs/EAAs helps preserve lean muscle mass on a calorie-restricted diet and during strenuous training sessions. 

BCAAs and EAAs are typically taken before, during, or after physical exercise. Standard dosage ranges from 5 to 10 grams, with varying amino acid ratios.

4. L-Glutamine

L-glutamine is the most abundant amino acid in the body and plays a vital role in various physiological functions, including immune support and recovery. As an important fuel source for lymphocytes and other immune cells, glutamine bolsters the immune system during periods of intense training [9].

Additionally, supplementation can aid gut health and reduce muscle damage after working out [10]. Research indicates that glutamine supplementation may also positively impact muscle hydration by acting as a cell volumizer, thereby enhancing muscle growth and strength [11]. A common glutamine dosing strategy is ingesting 5-10 grams post-workout to expedite recovery processes and bolster immune function. 

Maximizing Muscle Growth with Natural Bodybuilding Supplements

While some argue that natural bodybuilding shouldn't include dietary supplements, most competitive athletes and bodybuilders will (rightfully) argue that taking supplements is essential for achieving optimal results and reaching one's genetic potential. 

Recognized bodybuilding associations, including the World Natural Bodybuilding Federation and the International Federation of Bodybuilding and Fitness, clarify that natural bodybuilding means avoiding performance-enhancing drugs and artificial implants. This may include legal and illegal substances, anabolic steroids, growth hormones, and muscle implants.

However, if you’re keen to compete in a natural bodybuilding competition, know there are plenty of safe, effective, and natural supplements you can take. In fact, BCAAs/EAAs, creatine, glutamine, and whey protein are naturally occurring nutrients and arguably the most effective supplements for natural bodybuilders.