Vitamins and minerals are micronutrients that are crucial for health and performance. They are involved in a huge array of processes in the body, such as energy production, maintaining blood and bone health, immune function, and protecting the body against oxidative damage caused by the production of reactive oxygen species. It is essential for runners to include essential micronutrients in their meals and overall nutrition regime.   

Which are the necessary vitamins and minerals for runners?

Here, we explain the types and functions of micronutrients for runners that are of specific importance.

1. Magnesium

Magnesium is indispensable as it supports the healthy function of the nervous and musculoskeletal systems. Endurance runners are at greater risk of magnesium-deficiency due to losses through urine and sweat, and the dietary reference intake of 300mg-400mg/day for the general population is likely not sufficient for athletic people. Sub-optimal magnesium increases the amount of oxygen athletes require to complete moderate-intensity exercise and reduces endurance performance. 

Taking magnesium supplements may be a useful strategy for athletes to recoup the deficiency that occurred due to urine and sweat. Although the daily magnesium intake for athletes is not defined, they need to consume much more than 300mg-400mg/per day that is suggested for non-athletes. It is  advisable to determine the appropriate dosage under the supervision of a medical professional to avoid magnesium toxicity. 

2. Iron, vitamin B12, and folate

Iron is vital to endurance runners as the body uses it to make hemoglobin, a protein in red blood cells that carries oxygen from the heart to other parts of the body. It is also used in the production of myoglobin, a protein that delivers oxygen to muscles.

Iron-deficiency will result in anemia, which impairs oxygen delivery to your muscles, and impacts exercise performance. Endurance athletes should get their blood ferritin levels checked regularly and discuss the need for iron supplementation based on these results.

The prevalence of iron-deficiency is greater in female athletes due to various reasons and studies show that oral iron supplementation can improve iron status and physical performance. But it is recommended to manage this requirement under the close supervision of a medical professional. 

Also read: Vitamin B12: Benefits, Sources, and Deficiency

Vitamin B12 and folate are also necessary for endurance runners. Both are important for the production of healthy red blood cells as well as many other functions that deliver oxygen throughout the body. Deficiency in either of these micronutrients can result in anemia (low number of red blood cells), which can hamper performance. Animal-based products like meat and dairy are a major source of vitamin B12. So vegetarians or vegans might need to supplement with this vitamin to ensure adequate intake.

3. Zinc

You can obtain zinc in your diet by eating items like shellfish, green leafy vegetables, and seeds. Zinc-deficiency can disrupt your levels of thyroid hormone, which can affect your metabolic rate and exercise performance. Zinc also plays a pivotal role in muscle repair, immune health, and energy metabolism. Athletes are at a high risk of zinc-deficiency, so it is advisable to achieve sufficient intake through the aforementioned food sources. Exceeding the Upper Intake Level (40 mg/day) can affect the bioavailability of other important micronutrients, such as iron and copper. So monitor your zinc levels and the need for supplementation under the supervision of a medical professional. 

4. Vitamin D and calcium

Vitamin D and calcium play crucial roles in the growth, maintenance, and repair of bone tissue. Moreover, these vitamins and minerals help in the development and function of muscles in response to training. Deficiency in either or both of these micronutrients can increase the risk of low bone mineral density and stress fractures, a common injury in the lower limbs of endurance runners.

Also read: Vitamin D: Role, Sources, and Deficiency

A study published in the Journal of the International Society of Sports Nutrition found that three weeks of supplementation with vitamin D (2000 IU(International Units)/day) increased basal levels in the blood serum of ultra-endurance runners. Supplementation also decreased blood markers of muscle injury, such as creatine kinase, myoglobin, and troponin after a bout of eccentric exercise. So supplementation with vitamin D may help prevent muscle injury in runners. 

5. Antioxidants

When we engage in exercise, free radicals or reactive oxygen species are released. Whilst this process has some beneficial effects on the body, these chemicals can cause oxidative damage that is also referred to as oxidative stress. Antioxidant vitamins and minerals, such as vitamins C and E, beta-carotene, and selenium can be consumed to offset these effects. 

According to evidence, the best method to obtain all the natural antioxidants needed for health and performance is by consuming a diet rich in fresh fruits and vegetables, whole grains, legumes and beans, sprouts, and seeds. 

What should endurance runners keep in mind?

As an endurance runner, you need to follow a varied and balanced diet to derive most of the essential micronutrients that we have explained here. That being said, there are no Recommended Daily Allowance (RDA) values specifically in place for athletes. The only way to be sure that you are obtaining the required vitamins and minerals for optimal health and performance is to get regular blood tests done under the supervision of your medical professional. Make it a point to undergo these tests while making modifications to your nutrition and/or training regime. Once you do this, your medical practitioner can ascertain which vitamins and minerals need to be added to your diet.

References
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