5 Supplements and How They Impact Performance


By Erik Bustillo, MS, RD, FISSN, CISSN, CSC, CF-OL1, CPT


Supplements are meant to supplement, not necessarily replace. This is why they are called supplements, as in being supplemental to one’s diet, and not called instead-ofs. The supplement industry is estimated to have a market size/value of over $39 billion, safe to say marketing is working and folks are interested in doing what they can do to support their health and performance. Supplements should not be seen as the only path or solution to a desired outcome(s), but simply a tool to help slightly move the needle in what practitioners and athletes view as the right direction towards said desired outcome(s). The intention of this article is to help navigate the supplement world as well as review several supplements that you may or may not be familiar with.

Prior to supplementing, individuals should consider speaking with a registered dietitian to help navigate any recent blood work, navigate the supplement world, and the science or lack thereof surrounding supplements. These are things to consider and questions to ask prior to supplementing:

  • Why do I want to take this/what is my desired outcome?
  • What does the evidence/scientific literature show?
  • Do I have a deficiency/have I had recent lab work to help identify a deficiency?
  • Is it generally regarded as safe?
  • Has it been third party tested to ensure truth to the label and check for banned substances? 


Contrary to popular belief, supplements are regulated by the Food and Drug Administration (F.D.A.); however, they are not closely monitored the way medications are. In fact, oftentimes, attention has to be drawn to an adverse event (or several) involving a supplement for it to capture the attention of the F.D.A. This is why having the support of a healthcare professional is important and can help determine whether or not to supplement and what to supplement with.

5 Nutrients to Consider Supplementing and Why:

Protein (powder) 


There are several myths & misconceptions regarding protein powder such as:

  • They are bad for kidneys and bones
  • They are not food which means they must be bad
  • They cause fat storage/weight gain


The truth about protein supplements is that they are simply an easy, portable way to ensure adequate protein is being consumed. Protein powders are safe for healthy people to consume, including children. Saying protein powder is unsafe is akin to saying drinking milk (whey & casein) or eating peas is unsafe. Protein powder is simply a processed, easier way to consume & digest (assuming no allergies) protein. Protein powders help:

  • Enhance recovery from training
  • Build muscle
  • Decrease body fat when in a caloric deficit


Whereas lack of protein can result in decreased recovery/ immune function and increased appetite.

When considering whether or not to use a protein powder, consider the following:

  • Do I have an allergy/negative reaction?
  • Do I like how it tastes?
  • Is it affordable for me?
  • Do I have somewhere to store it (both at home and when taken with you to work, gym, school, etc.)


After considering those points, if you decide to use a supplement or not, for the tactical athlete population, consider taking 1.6-2.2g/kg of body weight. Here is an example of a 200lb person:

200 / 2.2 = 90.9kg x 1.6= 145g (lower end of the range) 90.9x 2.2= 200g of protein per day

Omega 3 Fish Oil

These omega 3 fatty acids are important for brain health/development as well as heart health, particularly EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Omega 3 has been touted for its potential anti-inflammatory benefits. A few good examples of omega 3 containing foods are salmon, mackerel, and flaxseed. Fish oil has been shown to decrease triglycerides and shows potential benefits in decreasing symptoms of depression.

If considering taking omega 3 fish oil or krill oil, ensure there are no allergies present. To help determine how much to take, studies show that one should take a minimum of 1,000mg or 1g of EPA and DHA.


  • Look for EPA and DHA on a label
  • Add the EPA + DHA
  • The sum should equal a minimum of 1,000mg
  • When reading the label, consider the serving size. If the serving size reads “2 softgels,” this means the amount on the label is for 2 softgels


Math example—2 softgels = EPA 400mg + DHA 250mg= 650mg= ideally, take a minimum of 4 softgels

Creatine monohydrate

Creatine is a nutrient made up of amino acids (“building blocks” of our bodies because they make up the proteins we consume and help our body build & repair tissues, among other things). It is naturally and mostly found in beef, and seafood. Humans also produce creatine, but not enough to get the performance and health benefits seen from supplementation. Creatine has been shown to enhance recovery, build muscle, and help performance such as lifting more weight and helping to increase power output for sprinting or jumping.

If taking creatine, the most studied form is creatine monohydrate. It is effective and safe for healthy individuals. Historically, it was thought that a loading phase was necessary, but this is incorrect. Loading (i.e. taking 20g several times a day for 1-2 weeks) works to help saturate muscle creatine stores faster, but for most people, this is not needed. Simply taking 3-5g daily can be helpful. For potential brain benefits, using the Candow method named after researcher Dr. Darren Candow who has recommended taking 0.1g/kg. For example, a 70kg person would take– .1×70= 7g of creatine monohydrate.

Vitamin D

Vitamin D is a fat soluble vitamin, this means it is absorbed in the presence of fat. It is also a vitamin that acts as a pre-hormone because it is important in the production of other hormones such as testosterone. The human body produces vitamin D upon the skin making contact with sunlight, there are also some food sources such as sockeye salmon, mushrooms, milk, and vitamin D fortified products. This vitamin/pro-hormone type vitamin is vital in the development of bones and it is also important for the human immune system.

If one were to supplement with vitamin D, having blood work done beforehand is a responsible way of going about supplementing. Where these levels are will dictate how much one would use in supplement form, often ranging from 1,000 IU to 10,000 IU. If one were to focus on the natural way of increasing vitamin D levels, they would focus on getting maximum skin exposure to sunlight ranging anywhere from 15-30 minutes, 2-4 days a week.


L-Theanine is an amino acid that helps with increasing feelings of relaxation. This is not a very popular supplement, but it is growing in recognition. It is naturally found in tea and has been studied with caffeine. If someone is an avid caffeine drinker, L-Theanine is something to consider. It is especially something to consider if the person who is taking a caffeinated product experiences jitteriness. Taking 200mg with caffeine has been shown to decrease feelings of jitteriness and may also help with improving visual attention tasks and decreasing reaction time response.


Not all supplements are created equal; therefore, it is imperative to know the quality and brand of what will be used. Have a conversation with your registered dietitian and physician before supplementing, especially if you have any medical conditions.

5 supplements to consider using are:

  • Protein powders
  • Omega fish oil
  • Creatine monohydrate
  • Vitamin D
  • L-Theanine


Getting blood tests done beforehand is recommended to help with dosage suggestions. Prior to supplementing, one should make it a point to evaluate their diet and truly understand why they want to supplement, what studies show, and how supplementing may impact them. Remember, supplements are supplemental to the diet.



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