To Supplement or Not To Supplement?

One of the number one questions that I receive as a Registered Dietitian is, “Should I be taking supplements?”. My answer is always, “Well… it depends.”

Start with skepticism

Screen Shot 2019-08-08 at 11.25.23 PM.png

Let’s start with some background info:

The dietary supplement market generates $124 BILLION in sales, every year, and it is rapidly growing. In my opinion, this is closely linked to our cultural obsession with dieting, six-pack abs, glowing skin, and our on-going search for the next quick fix, pill, and just about anything to distract us from what really matters: our relationship to food, movement, and our mental health. Regardless, you should know that the companies that make supplements are generally very profitable, well funded, and put a lot of dollars into advanced marketing to convince you that you need supplements. Their best interest may not be your best interest.

Also important: THE DIETARY SUPPLEMENT INDUSTRY IS UNREGULATED! Although your supplements may make health claims, much like prescriptions, there is no agency that monitors the efficacy, purity, safety, or ingredients of dietary supplements. Supplements can be contaminated with unsafe ingredients, or simply not contain what they claim to. Case in point: In 2018, a US Olympian, Madisyn Cox, was banned from competition after testing positive for a banned substance. No, she wasn’t doping or on drugs. She was taking a multivitamin that was contaminated with a banned substance. 

There are third party organizations that test supplements for their purity, but because of the big money in this industry, many smaller companies, especially the newer ones to hit the market that are advertising on your Insta feed, cannot afford this type of testing. Please note that I am not saying that the supplement companies are trying to poison you. However, we simply don’t know for sure what is in a lot of supplements, and we can’t necessarily trust marketing claims alone. 

Most importantly, your body absorbs and metabolizes vitamins and minerals from real food sources better than supplement form. A supplement will never take the place of proper nutrition, appropriate amounts of movement and exercise, rest, and recovery. 

So, you should approach ANY supplement with a healthy dose of skepticism.

 Now, let’s get down to the real question. Should you be taking a supplement? Well let’s lay out a few situations where it may be a good idea:

Elimination of Foods

If you eliminate foods due to allergens or dietary preferences (i.e vegan or vegetarian), you might want to consider a supplement. Anytime you are eliminating an entire food group, you are inherently eliminating a large portion of nutrients. If you are celiac, or gluten intolerant, you may not be getting enough B-vitamins, magnesium, or selenium.

 If you are vegan or vegetarian, depending on how intentional you are about your diet, you may be missing omega-3 fatty acids (specifically EPA and DHA), B12, vitamin D, iodine, and iron (especially if you’re female).

 If you’re on a carnivore diet…. Well, let’s not even go there. 

Side note: Don’t forget to check yourself, and make sure that you aren’t eliminating foods because of diet culture, and that the food choices you make are truly YOUR CHOICES. Don’t just assume that going gluten free or vegan will be healthier because that’s what everyone is talking about.

So you’re an athlete…

Athletes are HIGHLY marketed to in the supplement industry. Supplements will claim to enhance recovery, improve performance, and do just about everything else under the sun. So before we go any further, you should not trust the claims of most supplements on face value alone. You need to reflect honestly on your own situation and needs.

Then, it’s worth pointing out that not all athletes are the same. An endurance runner is a different beast than a dancer, or a track thrower, or a bodybuilder. The type of athlete that you are, and the amount of time that you spend training, is going to factor into your need for supplementation. Are you a weekend warrior, with relatively low training volume during the week and spikes on weekends? Then, you may not need to replace a large amount of nutrients. But are you an endurance athlete, who is pushing volumes of 40-50 miles or 10-20 hours of training per week, who doesn’t really have time to cook, and works a full time job? Then yes, maybe we should look into some supplementation. 

Certain athletes may need to replace higher amounts of iron, B-vitamins, zinc, vitamin D, calcium, magnesium, selenium, potassium, sodium, antioxidants, and specific amino acids (proteins). Of course, these needs can vary widely based on sport and intake of, you know, actual food.

We should also keep in mind that women and men are not the same, and women are not miniature men. The vast majority of research is conducted in men, therefore, nutrient recommendations are generally based on men. Women need higher amounts of iron and folic acid, depending on their age. 

From there, we can look at real, peer-reviewed research. Some supplements show actual efficacy, while others do not. For example, there is some research saying that nutrients like nitrates found in beets, may help with vasodilation and increase the amount of oxygen delivered to your muscles. Creatine is also one of the most researched supplements in the industry, and has a lot of validated research showing that it can help enhance strength and improve performance. 

All of this sounds super promising right? Well… maybe. We also have to look at what’s called the “effect size.” If there is a positive benefit, how much of a benefit is it, and does that matter? Many supplements only give a small marginal benefit, say 1-2% improvement, that probably doesn’t matter all that much unless you are competing at a professional level. So supplementation may not be worth the cost, or potential side effects, but a barely noticeable improvement. And, keep in mind the incredible power of the placebo effect. If we spend money on something and take it every day, then of course we want it to work. It’s easy and common to seemingly experience some small subjective benefits simply due to placebo.

So, if you are an athlete, should you take a supplement? Well, we’re back to where we started… it depends. Some supplements can be really beneficial for athletes and even necessary. But even the best supplement won’t be able to take the place of adequate nutrition, proper hydration, planning your fueling around workouts, and most of all, rest and sleep. Before you decide to take a supplement, we need to consider and optimize all of those factors, then strategically supplement if there’s something lacking.

Pregnant or lactating

Prenatal vitamins are generally part of a pregnant female’s daily routine. When you are pregnant, you are your child’s only source of nutrition, if you aren’t optimized, than it is likely that your baby isn’t either. Some claim that if you eat a balanced diet, you don’t need to take a prenatal. But what is a balanced diet? A balanced diet consists of 1-2 fruits per day, 2-3 servings of grains per day, 2-3 cups of vegetables per day, protein at every meal, and fats with every meal. If you’re thinking to yourself, “I do that some days….?”, then no, you probably don't eat a balanced diet and you may want to take a prenatal. Prenatal vitamins are basically a beefed up multivitamin that often contain higher amounts of folic acid, iron, omega-3s, calcium and vitamin D. Why these nutrients, you ask? 

  • Folic acid helps prevent neural tube defects and is essential when a baby’s brain and spinal cord are developing. Pretty important.

  • Iron is essential to produce healthy red blood cells that carry oxygen to cells. Also V important.

  • Omega-3s are also essential in brain development.

  • Calcium and vitamin D are important to help support growth of healthy bones.


We are learning more and more everyday about genetics and how they impact our utilization of nutrients and metabolism. This is an emerging field, and we are not yet able to use genetics to recommend specific vitamins for everyone. However, researchers are uncovering a few gene variations that may inhibit your body from making or utilizing certain nutrients. A few examples of this would be B12, folate and vitamin D. For those who have certain genetic variants, it may be beneficial to take a supplement. Ask your doctor or Registered Dietitian to see if this may be appropriate for you -- don’t just shoot in the dark. Certain vitamins are fat-soluble, and you can indeed overdo it and cause harm.

Everyone else

Okay, so you’re not exactly an athlete, you’re not pregnant, and you don’t think you have a genetic variant. You’re just trying to vibe right?

The majority of our vitamins and minerals come from plant foods. Did you know that according to the CDC, only 1 in 10 adults get enough fruits and vegetables? If you are one of those 9 adults, and cannot honestly say that you get 1-2 fruits per day, 2-3 servings of grains per day, 2-3 cups of vegetables per day, protein at every meal, and fats with every meal, then you should just take a pill right? 

Well, no. We should address your diet and get you some more nutrients. Plant foods do not only contain vitamins and minerals but they are our only source of dietary fiber, which is essential for a healthy digestive tract. A vitamin or supplement cannot replace all of the benefits of healthy plant-based foods. But if you travel a lot, or can’t eat a lot of vegetables or fiber containing foods due to certain digestive conditions, then a supplement may be a good option.

Moral of the story: Let’s finish where we started. Always remember, your body absorbs and metabolizes vitamins and minerals from real food sources better than supplement form. A supplement will never take the place of nutrition, appropriate amounts of exercise, rest and recovery. 

In my clinical practice, I try to keep supplementation simple. This usually starts with a high quality multivitamin, and possibly some omega-3’s and a protein supplement, although even this can vary widely. Some specific conditions require more nuanced supplementation, but that is beyond the scope of this article. If you are any of the groups discussed above, it may not be a bad idea to start with a high quality multivitamin. If you’re an athlete that is going to get drug tested, then you’ll want to choose a product that is verified by one or more third party testing agencies. These include:

And remember, If you have specific questions about supplementation, quality vitamins, or optimizing your nutrition, you can book a free 15-minute phone call with Abby Chan, EVOLVE Flagstaff’s Registered Dietitian.

Abby Chan