The Most Important Nutrients for Runners

Jennifer O'Donnell-Giles | May 20, 2016

Running can be one of the best exercises for your body. Not only is running an aerobic exercise, which can increase your heart health, it can actually work out your entire body, down from your legs all the way up to your arms!

Whether you’re a veteran runner or a beginner, diet plays a crucial role in how you feel when you run; proper nutrition will help you feel stronger so that you can go faster and farther. On the flip side, poor nutrition will make you feel sluggish and slow.

Processed foods that are high in salt, sugar, fats, dyes, and preservatives can hinder improvement in your running. By eating a well-rounded and balanced diet of whole, non-processed foods, all runners will be able to perform to their maximum potential!

Here are some of the most performance-optimizing nutrients runners should include in their daily diets.

Vitamin A

Runners often don’t think about how important eyesight is. Vitamin A supports healthy vision, which is helpful for avoiding pot holes in the road and reading signs on unfamiliar routes during runs. You can maintain a better pace if you can optimally see your surroundings, whether you’re out at dawn, dusk, or even at night. Foods that are rich in vitamin A include sweet potatoes, cantaloupe, kale, and other dark leafy greens.

Vitamin B12 and Iron

Vitamin B12 and iron both help carry oxygen throughout the body, which is essential for peak muscle performance. The lack of these nutrients can cause fatigue and lead to anemia. Good sources of vitamin B12 include milk and lean beef. You can also find iron in lentils and dark meat poultry.


Bone health is crucial for runners because bones are connected to muscles, which drive our running. Calcium is known for supporting strong bones, but can also promote cardiac health by regulating the electrical system of the heart. Additionally, calcium works alongside other electrolytes, like sodium and potassium, to regulate fluid balance and prevent fatigue and dehydration after a run. Excellent sources of calcium include yogurt, milk, cheese, spinach, tofu, and chia seeds.

Vitamin C

Most people run outdoors, which exposes them to carcinogenic elements, such as car emissions and pollution that can also cause inflammation. Vitamin C, which is a powerful antioxidant, helps negate the effects of those elements. Plus, it improves immune function to ensure that you’re healthy enough to keep on running. Vitamin C also enhances the absorption of iron to prevent fatigue. The best sources of vitamin C include kiwis, strawberries, and bell peppers.

Sodium and Potassium

These electrolytes help you maintain proper fluid balance and prevent muscle cramps on long, hot runs. Eating plenty of fruits and vegetables daily is an excellent way to get your potassium. Foods highest in potassium include bananas, oranges, whole grains, and potatoes.

Sodium is found in most packaged foods, which can be problematic for runners who want to avoid processed foods. In these cases, you can opt for water with electrolyte tablets or other electrolyte replacements. Foods that are naturally rich in sodium include celery, cheese, and milk.


Like vitamin C, zinc helps support a healthy immune system to prevent illnesses that would keep you from running. It can also aid in the metabolic breakdown of carbohydrates, which provides more available energy during a run. Sunflower seeds, grass-fed lean beef, and hummus are great sources of zinc.

By eating a balanced diet that’s packed with these nutrients, you can ensure that your body is well-nourished and ready for a good run!

Jennifer O'Donnell-Giles's profile picture

Jennifer O'Donnell-Giles

Jenn Giles, R.D., C.S.S.D. is all about health and wellness. She has over 15 years’ experience, including a dual master’s degree in Nutrition and Exercise Physiology from Columbia University. She is a Registered Dietitian (RD) and a Board Certified Specialist in Sports Dietetics (CSSD). She supplements all of this with her spin instructor certification and USATriathlon Level I Coach Certification.

Jennifer is passionate about (actually, obsessed with) the sport of triathlon. She has been personally participating in triathlons since 2000 and running road races since 1992. She is a two-time Ironman finisher and has completed countless numerous marathons. She has been a member of Power Bar Team Elite since 2006 and competed as a member of the 2006 Aquaphor/ Sponsored Athlete Team. She was ranked as USAT All American Honorable mention in 2006 and 2011. Jennifer does all of this along side of her husband, Patrick, who is an equally accomplished triathlete and runner. They try as hard as they can to do all of their training and racing together.

She will tell you, however, that her most important, most rewarding and most challenging job is as a mother of four. She knows first hand the challenges of maintaining optimal fitness, overall good health and achieving goals while raising a family - of which good nutrition is the cornerstone.

Most importantly, she knows how to motivate, inspire and challenge athletes based on their own abilities, strengths and everyday lifestyles. She believes there is an athlete in everyone - no matter what their abilities are – and if those abilities are manifold, then there is an even better athlete in there!

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