Should I be taking a supplement?

You can walk into most grocery stores in the United States and there is an aisle full of supplements. Do you ever ask yourself "Will taking a supplement make a difference in how I feel?" or "Do I really need to take this?". As an athlete, I never had a good grasp of what supplements I 'should' be taking to help my day-to-day and athletic performance.

Here's an easy breakdown of if you need to supplement, what you should supplement, and when you should supplement as an athlete.

We all know that vitamins and minerals are not only of fundamental importance to numerous human functions but essential in optimizing athlete performance. Athletes incur a high turnover of key vitamins and minerals, making them dependent on sufficient energy intake to replenish nutrient stores. However, for various reasons, athletes have difficulty properly replenishing their energy, vitamins, and mineral needs. While a ‘food first approach’ to meet nutrient requirements is the primary goal, it may be important for some athletes to consider a vitamin or mineral supplement, when appropriate, to meet their daily needs.

While most vitamins and minerals are more readily absorbed when ingested from food, supplements may need to be taken when athletes have compromised nutrient/energy intake (vegetarian/vegans), poor diet quality, are living/training at altitude, or are in a heavy training cycle.

Why can’t I just take a multivitamin and call it a day?

Multi-vitamins may be optimal for individuals who aren’t focused on optimizing athletic performance. An issue with multivitamins (or blindly supplementing for that matter) is that they may mask deficiencies, certain food or nutrient interactions can counteract the absorption of vitamins and minerals, you may not need the multivitamin (there is no benefit in taking a supplement when you don’t have a deficiency and over-supplementing has potential harm), and supplements are expensive!

Are athletes at a greater risk for deficiency?

There are a multitude of interacting factors that may contribute to sub-optimal nutrient status in athletes. This includes increased excretion of sweat, urine, and feces during and after training, increased turnover of nutrients, decreased absorption in the gastrointestinal tract, and biochemical adaptation to training.

Broad vitamin and mineral deficiencies are uncommon in athletes because the increased energy requirements of training are generally met with increased overall energy intake. However, this isn’t always the case. For example, when endurance athletes increase their training load, their energy intake may be compromised because they have fewer opportunities throughout the day to appropriately refuel in between training sessions. In addition, athletes in weight-sensitive sports may have low energy availability (RED-S). Compromised or restricted nutrient intake to manipulate body composition or weight will not only impact the athlete’s energy status but also the opportunity to replace any vitamins and minerals utilized or excreted during training or races. This decreases their training adaptation, increases the chance of vitamin or mineral deficiency, and increases the risk of injury.

Important Vitamins & Minerals for Athletes

If you’re feeling abnormally lethargic (more so than your normal training fatigue), it would be a good idea to get the following tested. In addition, these vitamins and minerals will be most impactful to athletic performance, and should be prioritized when fueling:

• Vitamin B9, Folate: Important in red blood cell production. Works synergistically with Vitamin B12. This is the only vitamin where the synthetic form (folic acid) is more readily absorbed than the form found naturally.

  • Testing: Serum Folate; 6-20ng/mL

  • Daily need for athletes: 400-800mcg Folic Acid

• Vitamin B12, Cobalamin: Important in red blood cell production. Works synergistically with Vitamin B9, especially pertinent in vegetarian and vegan athletes, as Vitamin B12 is most readily found in animal food sources.

  • Testing: Vitamin B12 Concentration; 400-700pg/mL

  • Daily Need: 2.4mcg Vitamin B12

• Vitamin C: Important in immune function and as an antioxidant. During infection or sickness, Vitamin C levels in white blood cells can fall by up to 50%, which has been linked to oxidative stress. Vitamin C intake preserves athlete health, especially during infection or a heavy training cycle when inflammation and oxidative stress acutely increase. Increases iron absorption.

  • Testing: N/A

  • Daily Need: 100-1000mcg Vitamin C, absorption decreases with increased intake

• Vitamin D: Important in bone metabolism, calcium homeostasis (bone health), and mitigating fracture risks.

  • Testing: 25-hydroxy Vitamin D; >40ng/mL

  • Daily Need: 1000-2000IU Vitamin D3 or 15’ of skin-exposed sunlight between 10 am-3 pm in the spring, summer, or fall can produce 250-500mcg Vitamin D3

• Calcium: Important for bone metabolism and bone health.

  • Testing:  Bone mineral density via CT scans or DXA scans

  • Daily Need: 1000mg/day, calcium intake should be taken in smaller doses throughout the day for optimal absorption

• Iron: Important in red blood cell production, specifically for hemoglobin. Should not be taken with Calcium as it decreases Iron absorption. Should not be taken with Zinc. Should be taken with Vitamin C for increased absorption.

  • Testing: Serum ferritin concentrations; 40-90ng/mL

  • Daily Need: 325mg ferrous sulfate per day when <30ng/mL

• Zinc: Important for immune function and inflammation. Studies show that 75mg/day of zinc within the first 24 hours of illness symptoms reduces the duration of sickness by 33%.

  • Testing: Serum or plasma zinc, with fasting concentrations >70ug/dL

  • Daily Need: 11mg for men, 8mg for women

A few additional notes regarding supplementation:

• The daily need listed under each vitamin/mineral is not solely from supplements – it is the cumulative recommended amount from all foods throughout the day. The daily need should be focused on if you are taking a supplement and have a deficiency- otherwise, a varied diet of fruits, vegetables, lean meats, and nuts/seeds should be sufficient in meeting your daily needs.

• If you do not have a deficiency, you most likely do not need to supplement. Studies show that an additional intake of most vitamins/minerals in the absence of a deficiency does not provide any additional boost in athletic performance or daily function.

Strategies to prevent and treat nutrient deficiency

First, always consult a registered dietitian nutritionist, or sports medicine doctor if you are concerned about a potential vitamin or mineral deficiency. While an initial approach might be ‘food first’, this is only effective when there is an obvious and addressable issue with diet composition or energy intake. The process of replenishing a vitamin or mineral deficiency can be slow (4-12 weeks in the case of Vitamin D and Iron), and supplementation can cause gastrointestinal distress.

• Eat a varied diet of fruits, vegetables, lean meats, and nuts/seeds.

• Get your blood tested annually with the tests listed above. If there is a deficiency, test every three months until the deficiency is resolved. Remember, blood tests are just a snapshot in time and reflective of your exercise, nutrition, and hydration at that time. To get the most accurate reading of your blood values, get tested while fasting, do not get tested the day after a hard/strenuous workout, and ensure you’re hydrated when you are tested.

Want a summary of all this info? Click below for our FREE Athlete’s Guide to Supplementation Cheat Sheet!

Athlete's Guide to Supplementation.pdf

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