Rooting for a Better Heart: How Beets Power Cardiovascular Performance

Arguably one of the most divisive vegetable crops on the market, Beta vulgaris, the table beet, conjures a variety of reactions. Love them or hate them, beets are making a comeback, not just on the dinner plate, but in the workout routine. This hardy root vegetable is beeting the odds when it comes to distinguishing itself from other trendy health supplements.

Beets are one of many vegetables often described as a superfood, or a food with a notably high nutrient density. For those with an aversion to beets in their natural state, beets can be processed into a powder or juice for a more subtle alternative that can be added to sauces, soups, and smoothies. These products have become trendy among fitness enthusiasts, who view beet consumption as a means to improve cardiovascular performance. But is beetroot powder just that, a trend? Or is there evidence to suggest that beets have a rightful place next to protein powder and creatine as an athletic supplement? Unlike many superfoods, the primary appeal of the beet does not rely on its antioxidant or vitamin content. When it comes to beets, nitrogen is what puts the super in superfood.

The nitrogen in beets comes in the form of nitrate, but there are concerns regarding the presence of nitrates in other foods, specifically cured meats. Cured meats contain added preservatives in the form of sodium nitrate and sodium nitrite,⁶ which can potentially form harmful compounds during digestion.⁵ While the extent of this risk is controversial, this has led to the association between dietary nitrates and an increased cancer risk in the public eye.⁵ Despite also being rich in dietary nitrates, beets are not linked with negative health effects, quite the opposite. If nitrates in both foods are chemically identical, what explains the difference? The outcome of consuming beets compared to cured meat comes down to how other molecules present in each food influence nitrate metabolism.

The pathway nitrates follow through the body is the same regardless of whether they come from beets or processed meat. When we eat something containing nitrate, it comes in contact with bacteria from salivary glands in the mouth which reduce nitrate (NO₃^–) into nitrite (NO₂^–).^{5, 8} The converted nitrite makes its way down to the stomach where it is further converted to nitric oxide (NO), which is an inert chemical responsible for healthy cardiovascular performance.^{5, 6}

Unfortunately, nitric oxide isn’t the only possible product of nitrite. The high acidity of the stomach allows potentially harmful intermediate nitrogenous compounds to form. ^{6, 9} When a hydrogen ion (H+) or a proton attaches to nitrite, the result is nitrous acid (HNO₂).⁹ Nitrous acid can be further converted to a compound called a NOC (N-nitroso compound). NOCs are the carcinogen responsible for the devastating health complications associated with a high consumption of some sources of dietary nitrogen, including various cancers and birth defects. ^{5, 9} The production of NOCs is enhanced when cured meat enters the equation. When meat is digested, amino acids are produced, which can then further react with the added nitrite to form NOCs. This chemical reaction is driven by haem, a molecule abundant in meat but absent in vegetables.⁵

It is here in the stomach where beets further distinguish themselves as a healthy source of dietary nitrogen. The formation of NOCs, called endogenous nitrosation, can be inhibited in the presence of non-nitrogenous compounds.^{6, 9} Unlike other nitrogen rich foods such as meat, beets are packed with these inhibitory compounds, including vitamin C and phenolic compounds. These compounds prevent the formation of harmful NOCs while aiding the stomach in forming nitrous oxide, which may be the key to enhancing athletic performance.^{2, 6, 9}

When we exercise, our bodies require additional oxygen. Oxygen introduced to the bloodstream is continuously delivered to power the muscles that push us through a workout, including the heart, the hardest working muscle in the body.⁸ But the body can only process a limited amount of oxygen at a time. The maximum amount of oxygen the body can use during exercise is known as the VO₂ max and is considered to be the best indicator of cardiovascular health.¹ The higher the VO₂ max, the more the body can use that existing oxygen to power muscles, indicating efficient blood flow by reducing the need for further oxygen intake.¹ This is in part why avid runners are less likely than the average person to be out of breath after running a mile; their bodies have been training to optimize oxygen circulation, reducing the need take in additional oxygen by heavy breathing. The nitrates in beets may just be another tool for our bodies to optimize oxygen use during a workout.

Given the role of oxygen in muscle performance, researchers have turned their attention to dietary nitrates as a means to improve oxygen efficiency during exercise. Although most nitrous oxide is produced in the stomach, the same reaction can also occur in other muscles.¹ Medical research has suggested that the reduction of nitrate to nitrous oxide is facilitated by a lack of oxygen, meaning that more nitrous oxide is produced in working muscles in need of oxygen.¹ The study that pioneered the beet’s place in human health and performance was published in 2009, following research examining the role of dietary nitrates in reducing high blood pressure.¹ This study explored the effects of supplementing beet juice as a source of dietary nitrogen to young men while performing moderate to high-intensity cycling. In those who were given increased dietary nitrates in the form of beet juice, there was a 5% net reduction of oxygen intake after a moderate cycling session, which is remarkably higher than has been achieved through long-term endurance training.¹ In intense cycling sessions, beet juice supplements resulted in a delay of exhaustion time by 16%.¹ Once nitrates are converted into nitrous oxide, they are introduced to the bloodstream where they promote blood vessel expansion.^{1, 2, 3, 9} This makes it easier for blood to flow throughout the circulatory system, quite literally opening up the cardiovascular system and reducing blood pressure.^{1, 2}  Ensuring a steady flow of blood and oxygen is critical both when exercising and in reducing high blood pressure. Medical researchers have begun linking dietary nitrates to heart health, making a compelling case for adding beets to the daily diet.

Since its initial debut into the medical realm, the cardiovascular benefits of dietary nitrate found in beets continue to be explored. A meta-analysis on 23 studies ranging from 2010 to 2016 on the athletic benefits of beets found that regular supplementation of beetroot juice or beet powder increases cardiovascular endurance.⁴ Variations in results were often due to differences in beet juice dosage and the intensity of exercise.⁴ A 2022 study of 218 patients with high blood pressure focused on determining how much beet juice would need to be consumed to see an impact on heart health. Although reduced blood pressure was significant in all patients, whether they consumed 70 mL, 140 mL, or 250 mL of beet juice per day over the course of up to 60 days, it was clear that the 250 mL dose delivered the happiest of hearts, with the most significant reduction in blood pressure.² For best results in powering a workout, athletes should keep in mind that nitrite concentrations peak two to three hours after an intake of dietary nitrate. This means that the benefits of beets are best captured when consumed appropriately 90 minutes before exercise.⁴

From the lab to the track, the beet has earned its place as something more than a trendy health supplement. Whether taken as a juice, supplement, or enjoyed whole, this versatile vegetable supports both nutrition and athletic performance. With its ability to improve cardiovascular performance, it might be time to rewrite the old saying. Forget the apple, it’s a beet a day to keep the doctor away!

References

1. Bailey, S. J., et al., (2009). Dietary nitrate supplementation reduces the O2 cost of low-intensity exercise and enhances tolerance to high-intensity exercise in humans. Journal of applied physiology (Bethesda, Md. : 1985), 107(4), 1144–1155. https://doi.org/10.1152/japplphysiol.00722.2009

2. Benjamim, C. J., et al. (2022). Nitrate Derived From Beetroot Juice Lowers Blood Pressure in Patients With Arterial Hypertension: A Systematic Review and Meta-Analysis. Frontiers in nutrition, 9, 823039. https://doi.org/10.3389/fnut.2022.823039

3. Clifford, T., et al., (2015). The potential benefits of red beetroot supplementation in health and disease. Nutrients, 7(4), 2801–2822. https://doi.org/10.3390/nu7042801

4. Domínguez, R., et al., (2017). Effects of Beetroot Juice Supplementation on Cardiorespiratory Endurance in Athletes. A Systematic Review. Nutrients, 9(1), 43. https://doi.org/10.3390/nu9010043

5. Kobayashi J. (2018). Effect of diet and gut environment on the gastrointestinal formation of N-nitroso compounds: A review. Nitric oxide : Biology and Chemistry, 73, 66–73. https://doi.org/10.1016/j.niox.2017.06.001

6. Kolb, Lorre., (n.d.). What’s the Deal with Nitrates and Nitrites Used in Meat Products?, University of Wisconsin – Madison Livestock Division of Extension, livestock.extension.wisc.edu/articles/whats-the-deal-with-nitrates-and-nitrates-used-in-meat-products/.

7. Ma, L., et al., (2018). Nitrate and Nitrite in Health and Disease. Aging and disease, 9(5), 938–945. https://doi.org/10.14336/AD.2017.1207

8. The Children’s Hospital of Philadelphia. (n.d.). How the normal heart works. The Children’s Hospital of Philadelphia. https://www.chop.edu/centers-programs/cardiac-center/how-normal-heart-works#:~:text=Located%20in%20the%20center%20of,and%20nutrients%20needed%20to%20survive.

9. Ward, M., et al., (2018). Drinking Water Nitrate and Human Health: An Updated Review. International journal of environmental research and public health, 15(7), 1557. https://doi.org/10.3390/ijerph15071557

About the Author

Leigha Fullerton      Root Vegetable Research Associate

As a Root Vegetable Research Associate, Leigha Fullerton contributes to the development of high-quality beet and carrot varieties within IFSI’s root vegetable breeding program. With a B.S. in Horticulture and German from the University of Wisconsin–Madison, Leigha brings several years of hands-on vegetable breeding experience gained during undergraduate research and internships. She is also a licensed drone pilot with training in aerial imaging to enhance trial evaluations. New to IFSI but deeply committed, Leigha is focused on building a strong foundation in plant breeding and advancing innovative solutions in crop development. She plans to begin a M.S. degree in Plant Breeding while continuing her applied breeding work with IFSI.