Research - Beetroot
Beets History and Traditional Use
Range and Habitat
The garden, or sugar, beet (Beta vulgaris, Chenopodiaceae) is an annual vegetable which forms a dense cluster of dark green leaves attached to a large, bulbous root.1 Both greens (aerial parts) and roots are edible. Beets typically are grown in the spring and fall; they thrive in cool seasons. In warmer climates, beets are grown in the winter as well. The leaves can grow up to 18 inches tall, though they are best harvested at two to three inches. The plant produces red-tinged green flowers. Though red beetroots are most commonly available commercially, golden and “candy cane” red and white roots also exist. The United States, France, Poland, Germany, and Russia currently are the leading producers of beets.2
Selective breeding has produced several different varietals of Beta vulgaris, including sugar beet (used for sugar extraction), mangel-wurzel (used as livestock fodder), and Swiss chard (B. vulgaris subsp. cicla).1Current research suggests that these varietals may help post-exercise muscle recovery, improve blood pressure, and combat dyslipidemia.
Phytochemicals and Constituents
Beets are nutritionally diverse, low in calories, cholesterol-free, and fat-free. Beet greens also are edible and contain calcium, vitamin A and carotenoids, vitamin C, and iron. 100 grams of beet greens contain 50% of the United States Department of Agriculture’s (USDA’s) Recommended Daily Allowance for vitamin C.2 Beetroots are a good source of folic acid, fiber, potassium, and manganese.3 They are also rich in niacin, vitamin B-6, pantothenic acid, iron, copper, magnesium, and manganese.
Like carrots, the color of beetroots indicates the different nutrient compounds contained within. Red beets contain phytochemicals called betalains*, which can also be found in Swiss chard, rhubarb (Rheum rhabarbarum, R. rhaponticum, Polygonaceae), and prickly pear cactus (Opuntia ficus-indica, Cactaceae).4Betanin, one of the most-studied betalains, has been shown to provide anti-inflammatory support in vitro and in animal models. Red beets contain 300-600 mg/kg of betanin, which gives this variety its signature ruby-red color. This is slightly unusual, since most red-colored foods owe their pigmentation to anthocyanins, another prevalent group of compounds with antioxidant actions. However, betanin has exceptionally high antioxidant activity, exhibiting 1.5-2 times more activity than its anthocyanin counterparts.
Golden, or yellow, beetroots have greater concentrations of lutein than red beets. In the human body, lutein is found in high concentrations in the retina of the eye, and may help protect the eye from abnormal light sensitivity and degenerative diseases such as cataracts and macular degeneration. Beet greens contain higher levels of lutein and zeaxanthin, a similar carotenoid that also promotes healthy vision.
Historical and Commercial Uses
Beets were first cultivated in the Mediterranean region and have a history of use that dates back over 4,000 years.5 Modern cultivated beets are descendants from a wild plant called the sea beet (B. vulgarissubsp. maritima), which grew wild in North Africa and on the Mediterranean coast.1 Initially, humans consumed only the greens, and the root was used for medicinal purposes or animal fodder.
Greek and Roman authors, including Theophrastus (3rd century BCE), Hippocrates (4th century BCE), Dioscorides (1st century CE), and Pliny the Elder (1st century CE), noted a wide variety of ailments they claimed could be cured or prevented by beetroot and greens consumption.6 The primary medicinal use of the beet was to detoxify the blood and cleanse the kidneys, liver, bowel, and gallbladder. Beets also were believed to contain aphrodisiac qualities, and carvings of beets were found on excavated frescoes from Greek brothels.7 Other conditions thought to be treated using beets included leprosy, wounds and skin disorders, dandruff, digestive issues, and earaches.6
Trade throughout Europe spread the growth of beets beyond the Mediterranean area, and the roots eventually evolved into the sweeter, more edible modern plant.4 The popularity of beets increased around the 16th century due to this careful cultivation. The high sugar content of the root made beets a significant economic crop in Europe in the 19th century as an alternative sweetener in the place of sugarcane (Saccharum officinarum, Poaceae). Currently, about 20-30% of the world’s sugar production comes from sugar beets.7
Today, the root and greens are consumed as a food product.8 The root can be prepared by boiling, roasting, baking, or pickling. Raw roots often are added to salads and soups. The greens can be prepared as any other bitter green, such as collard greens (Brassica oleracea, var. acephala, Brassicaceae). Beet juice and extract also are used as natural alternatives to red food dye and in various cosmetic products.9
Current research shows that supplementation with beet juice has been shown to play a role in human exercise tolerance and recovery. One human study concluded that beet juice supplementation reduced the negative effects associated with muscle hypoxia after exercise.10 Muscle hypoxia occurs when adequate oxygen is not available for normal muscle activity. This impairs exercise tolerance and energy production from muscles. Another clinical trial reported that supplementation of beetroot juice for three days prior to strenuous exercise reduced the amount of oxygen spent and increased exercise endurance by reducing the time of muscle failure onset.11 This effect remained true during moderate exercise as well.
Beets can affect blood pressure and dyslipidemia (a high level of cholesterol, triglycerides, or both in the blood), due to their high nitrate concentration. Dietary nitrates are converted to nitrites, which are known vasodilators (compounds which cause blood vessels to expand), in the body upon ingestion. Consumption of beet juice thus increases the concentration of plasma nitrites in the blood, which decreases blood pressure in healthy adults. When studying this effect, scientists also concluded that beet juice is protective against endothelial (related to the inner lining of arteries) damage, finding a decrease in systolic blood pressure by 6 mmHg after supplementation with beetroot juice.12
The nitrates in beets also aid in smooth muscle relaxation, further adding to its value as an exercise supplement.2 Professional and amateur athletes are increasingly adding beetroot juice to their exercise regimen, claiming an increase in stamina and decision-making speed following a promising 2015 study.13Researchers concluded that after a week of supplementation with beet juice, healthy male subjects showed increased reaction time and athletic performance during a sprinting exercise.14
Another study showed a significant decrease in blood pressure, with a change of 10.4 mmHg systolic and 8 mmHg diastolic measurements, due to the high nitrate concentration in beets. This study also suggested that beets can prevent endothelial dysfunction and inhibit platelet aggregation. These effects were attributed to the ingestion of nitrates that are converted to nitrites and then reduced to nitric oxide in the stomach.15 Supplementation of beetroot, combined with hawthorn (Crataegus spp, Rosaceae) berry, increased plasma nitrate and nitrite concentrations, and significantly reduced triglyceride levels in 72% of participants with elevated triglycerides.16
Eating a moderate amount of red beetroots or products colored with red beet extract may cause some individuals to experience a temporary reddening of the urine.4 This is known as “beeturia” and is not harmful. However, it may also be an indication of abnormal iron levels in the body or of a problem with iron metabolism, as those with these pre-existing conditions are more likely to experience “beeturia.”
Both root and greens of beets contain a high amount of oxalates, which may exacerbate conditions such as kidney stones. However, since beets also contain a high ratio of minerals to oxalates, the amount of bioavailability may be lower than foods with similar oxalic contents.17,18
* Betalains were first named as a unique set of pigments in 1968 by Andre Dreiding and the late Professor Tom J. Mabry, PhD, of the Department of Botany at the University of Texas at Austin. A world-renowned phytochemist and scholar, Mabry passed away in November 2015. Among his many academic distinctions and memberships, he was a former member of the ABC Advisory Board.
Macronutrient Profile: (Per 100g [approx. 3/4 cup] raw beetroot)
1.61 g protein
9.56 g carbohydrate
0.17 g fat
Secondary Metabolites: (Per 100g [approx. 3/4 cup] raw beetroot)
Excellent source of:
Folate: 109 mcg (27.25% DV)
Very good source of:
Manganese: 0.32 mg (16% DV)
Dietary Fiber: 2.8 g (11.2% DV)
Good source of:
Potassium: 325 mg (9.3% DV)
Vitamin C: 4.9 mg (8.17% DV)
Magnesium: 23 mg (5.75% DV)
Iron: 0.8 mg (4.44% DV)
Phosphorus: 40 mg (4% DV)
Vitamin B6: 0.07 mg (3.5% DV)
Riboflavin: 0.04 mg (2.35% DV)
Zinc: 0.35 mg (2.33% DV)
Thiamin: 0.03 mg (2% DV)
Niacin: 0.33 mg (1.65% DV)
Calcium: 16 mg (1.6% DV)
DV = Daily Value as established by the US Food and Drug Administration, based on a 2,000 calorie diet.
Recipe: Roasted Beets with Orange-Balsamic Glaze
- 1/2 pound fresh beets
- 2 tablespoons olive oil
- Salt and pepper to taste
- 1/2 cup balsamic vinegar
- 2 tablespoons freshly-squeezed orange juice
- 2 teaspoons sugar
- Heat oven to 350°F. Wash beets, scrubbing off any excess dirt, and trim off greens, if present.
- Place beets in the middle of a large sheet of aluminum foil. Coat with olive oil, then sprinkle with salt. Wrap beets in the foil and roast for about 1 hour, checking every 15 minutes after 1 hour of cooking time, until beets are easily pierced with a knife.
- Peel the skin off beets while they are still warm, but cool enough to handle. Take care with preparing cooked beets, as their vibrant red color will stain some surfaces and fabrics.
- Prepare the glaze by combining vinegar, orange juice, and sugar in a small saucepan over medium-high heat. Bring to a boil, then turn heat down to maintain a simmer until the mixture has thickened and coats the back of a spoon.
- To serve, thinly slice beets, then drizzle with glaze.
Source : American Botanical Council - Author Hannah Bauman
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Dietary nitrate improves sprint performance and cognitive function during prolonged intermittent exercise
- Christopher Thompson
- , Lee J. Wylie
- , Jonathan Fulford
- , James Kelly
- , Matthew I. Black
- ,Sinead T. J. McDonagh
- , Asker E. Jeukendrup
- , Anni Vanhatalo
- , Andrew M. Jones
It is possible that dietary nitrate (NO3 −) supplementation may improve both physical and cognitive performance via its influence on blood flow and cellular energetics.
To investigate the effects of dietary NO3 − supplementation on exercise performance and cognitive function during a prolonged intermittent sprint test (IST) protocol, which was designed to reflect typical work patterns during team sports.
In a double-blind randomised crossover study, 16 male team-sport players received NO3 −-rich (BR; 140 mL day−1; 12.8 mmol of NO3 −), and NO3 −-depleted (PL; 140 mL day−1; 0.08 mmol NO3 −) beetroot juice for 7 days. On day 7 of supplementation, subjects completed the IST (two 40-min “halves” of repeated 2-min blocks consisting of a 6-s “all-out” sprint, 100-s active recovery and 20 s of rest), on a cycle ergometer during which cognitive tasks were simultaneously performed.
Total work done during the sprints of the IST was greater in BR (123 ± 19 kJ) compared to PL (119 ± 17 kJ; P < 0.05). Reaction time of response to the cognitive tasks in the second half of the IST was improved in BR compared to PL (BR first half: 820 ± 96 vs. second half: 817 ± 86 ms; PL first half: 824 ± 114 vs. second half: 847 ± 118 ms; P < 0.05). There was no difference in response accuracy.
These findings suggest that dietary NO3 − enhances repeated sprint performance and may attenuate the decline in cognitive function (and specifically reaction time) that may occur during prolonged intermittent exercise.
Source : European Journal of Applied Physiology
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Beetroot juice supplementation speeds O2 uptake kinetics and improves exercise tolerance during severe-intensity exercise initiated from an elevated metabolic rate
Breese BC1, McNarry MA, Marwood S, Blackwell JR, Bailey SJ, Jones AM.
Recent research has suggested that dietary nitrate (NO3(-)) supplementation might alter the physiological responses to exercise via specific effects on type II muscle. Severe-intensity exercise initiated from an elevated metabolic rate would be expected to enhance the proportional activation of higher-order (type II) muscle fibers. The purpose of this study was, therefore, to test the hypothesis that, compared with placebo (PL), NO3(-)-rich beetroot juice (BR) supplementation would speed the phase II VO2 kinetics (τ(p)) and enhance exercise tolerance during severe-intensity exercise initiated from a baseline of moderate-intensity exercise. Nine healthy, physically active subjects were assigned in a randomized, double-blind, crossover design to receive BR (140 ml/day, containing ~8 mmol of NO3(-)) and PL (140 ml/day, containing ~0.003 mmol of NO3(-)) for 6 days. On days 4, 5, and 6 of the supplementation periods, subjects completed a double-step exercise protocol that included transitions from unloaded to moderate-intensity exercise (U→M) followed immediately by moderate to severe-intensity exercise (M→S). Compared with PL, BR elevated resting plasma nitrite concentration (PL: 65 ± 32 vs. BR: 348 ± 170 nM, P < 0.01) and reduced the VO2 τ(p) in M→S (PL: 46 ± 13 vs. BR: 36 ± 10 s, P < 0.05) but not U→M (PL: 25 ± 4 vs. BR: 27 ± 6 s, P > 0.05). During M→S exercise, the faster VO2 kinetics coincided with faster near-infrared spectroscopy-derived muscle [deoxyhemoglobin] kinetics (τ; PL: 20 ± 9 vs. BR: 10 ± 3 s, P < 0.05) and a 22% greater time-to-task failure (PL: 521 ± 158 vs. BR: 635 ± 258 s, P < 0.05). Dietary supplementation with NO3(-)-rich BR juice speeds VO2 kinetics and enhances exercise tolerance during severe-intensity exercise when initiated from an elevated metabolic rate.
Source : Am J Physiol Regul Integr Comp Physiol.
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A targeted approach for evaluating preclinical activity of botanical extracts for support of bone health
Yumei Lina1, Mary A. Murraya1, I. Ross Garretta2a3, Gloria E. Gutierreza2a4, Jeffry S. Nymana2a5, Gregory Mundya2a6 †, David Fasta7, Kevin W. Gellenbecka1 c1, Amitabh Chandraa7 and Shyam Ramakrishnana1a8
a1 Nutrilite Health Institute, 5600 Beach Boulevard, Buena Park, CA 90622, USA
a2 OsteoScreen Ltd, 2040 Babcock Road, San Antonio, TX 78023, USA
a3 9909 Charthouse Cove, Austin, TX 78730, USA
a4 Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238, USA
a5 Department of Orthopaedic Surgery and Rehabilitation, Vanderbilt University Medical Center, Nashville, TN 37232, USA
a6 Vanderbilt University Medical Center, Nashville, TN 37232, USA
a7 Access Business Group, 7575 East Fulton Avenue, Ada, MI 49355, USA
a8 The Himalaya Drug Company, Makali, Tumkur Road, Bangalore – 562123, India
Using a sequential in vitro/in vivo approach, we tested the ability of botanical extracts to influence biomarkers associated with bone resorption and bone formation. Pomegranate fruit and grape seed extracts were found to exhibit anti-resorptive activity by inhibiting receptor activator of nuclear factor-κB ligand (RANKL) expression in MG-63 cells and to reduce IL-1β-stimulated calvarial 45Ca loss. A combination of pomegranate fruit and grape seed extracts were shown to be effective at inhibiting bone loss in ovariectomised rats as demonstrated by standard histomorphometry, biomechanical and bone mineral density measurements. Quercetin and licorice extract exhibited bone formation activity as measured by bone morphogenetic protein-2 (BMP-2) promoter activation, increased expression of BMP-2 mRNA and protein levels, and promotion of bone growth in cultured mouse calvariae. A combination of quercetin and licorice extract demonstrated a potential for increasing bone mineral density in an intact female rat model as compared with controls. The results from this sequential in vitro/in vivo research model yielded botanical extract formulas that demonstrate significant potential benefits for bone health.
Source : The Journal of Nutritional Sciences
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Effects of a beetroot juice with high neobetanin content on the early-phase insulin response in healthy volunteers
Peter C. Wootton-Bearda1, Kirsten Brandta2, David Fella3, Sarah Warnera1a2 and Lisa Ryana1a4 c1
a1 Functional Food Centre, Oxford Brookes University, Gipsy Lane, Oxford OX3 0BP, UK
a2 Human Nutrition Research Centre, School of Agriculture and Rural Development, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
a3 Cell Systems Modelling Group, Oxford Brookes University, Gipsy Lane, Oxford OX3 0BP, UK
a4 Department of Nutrition and Dietetics, Monash University, Faculty of Medicine, Nursing and Health Sciences, 264 Ferntree Gully Road, Vic 3168, Australia
Produce rich in phytochemicals may alter postprandial glucose and insulin responses by interacting with the pathways that regulate glucose uptake and insulin secretion in humans. The aims of the present study were to assess the phytochemical constituents of red beetroot juice and to measure the postprandial glucose and insulin responses elicited by either 225 ml beetroot juice (BEET), a control beverage matched for macronutrient content (MCON) or a glucose beverage in healthy adults. Beetroot juice was a particularly rich source of betalain degradation compounds. The orange/yellow pigment neobetanin was measured in particularly high quantities (providing 1·3 g in the 225 ml). A total of sixteen healthy individuals were recruited, and consumed the test meals in a controlled single-blind cross-over design. Results revealed a significant lowering of the postprandial insulin response in the early phase (0–60 min) (P < 0·05) and a significantly lower glucose response in the 0–30 min phase (P < 0·05) in the BEET treatment compared with MCON. Betalains, polyphenols and dietary nitrate found in the beetroot juice may each contribute to the observed differences in the postprandial insulin concentration.
Source : Journal of Nutritional Science
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Effect of beetroot juice on lowering blood pressure in free-living, disease-free adults: a randomized, placebo-controlled trial
The consumption of beetroot juice on a low nitrate diet may lower blood pressure (BP) and therefore reduce the risk of cardiovascular events. However, it is unknown if its inclusion as part of a normal diet has a similar effect on BP. The aim of the study was to conduct a randomized controlled trial with free-living adults to investigate if consuming beetroot juice in addition to a normal diet produces a measureable reduction in BP.
Fifteen women and fifteen men participated in a double-blind, randomized, placebocontrolled, crossover study. Volunteers were randomized to receive 500 g of beetroot and apple juice (BJ) or a placebo juice (PL). Volunteers had BP measured at baseline and at least hourly for 24-h following juice consumption using an ambulatory blood pressure monitor (ABPM). Volunteers remained at the clinic for 1-h before resuming normal non-strenuous daily activities. The identical procedure was repeated 2-wk later with the drink (BJ or PL) not consumed on the first visit.
Overall, there was a trend (P=0.064) to lower systolic blood pressure (SBP) at 6-h after drinking BJ relative to PL. Analysis in men only (n=13) after adjustment for baseline differences demonstrated a significant (P<0.05) reduction in SBP of 4 – 5 mmHg at 6-h after drinking BJ.
Beetroot juice will lower BP in men when consumed as part of a normal diet in free-living healthy adults
Source Journal Nutrition
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Beetroot Juice May Reduce Blood Pressure Consuming beetroot juice may reduce blood pressure, according to a new study.
Beet is a flowering perennial plant that produces leaves and roots that are widely used as a food source in humans and animals. Beets are a source of vitamins A and C, iron, and other minerals, carotenoids and dietary fiber. Betalins are natural pigments (colors) in beets that account for the red color in beet stems and leaves. After eating beets, these pigments produce red or pink urine (called beeturia) in about 10-14 percent of people. The American Academy of Pediatrics recommends avoiding feeding beets and other high-nitrate foods to infants younger than three months of age to avoid the risk of nitrate poisoning.
Human studies have tested the effects of beet on blood sugar, cholesterol and blood pressure levels. However, results are mixed. Early evidence suggests that sugar beet fiber may modestly lower systolic blood pressure in patients with type 2 diabetes. Additional research is warranted.
In a new study, researchers conducted two separate studies to evaluate the effects of beetroot juice on blood pressure. People with normal blood pressure levels were randomly assigned to drink 0 grams, 100 grams, 250 grams or 500 grams of beetroot juice; or to eat a control bread product containing no beetroot juice, a bread product containing 100 grams of red beetroot juice or a bread product containing 100 grams white beetroot juice. Blood pressure was measured over 24 hours and nitrate levels in the urine were measured before treatment and again two hours, four hours and 24 hours after treatment.
The researchers found that consuming beetroot juice was significantly linked to reduced blood pressure over the 24-hour period. The authors noted that the reduction in blood pressure was almost dependent on the amount of beetroot juice consumed. Additionally, the researchers found that consuming both the red and white beetroot juice bread products were significantly linked to reduced blood pressure. With the exception of the white beetroot bread, all beetroot juice and bread products significantly increased nitrate levels in the urine after consumption.
The authors concluded that small amounts of beetroot juice may reduce blood pressure. Larger-scale, well-designed clinical trials are needed to further evaluate these findings.
In addition to beets, many other foods have been evaluated for their potential effects on blood pressure. Numerous human studies report that garlic may lower blood pressure, and some studies have suggested that chocolate may lower blood pressure. More research is needed.
For more information about integrative therapies for high blood pressure, please visit Natural Standard's Comparative Effectiveness Database.
For more information about beets, please visit Natural Standard's Foods, Herbs & Supplements Database.
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- Hobbs DA, Kaffa N, George TW, et al. Blood pressure-lowering effects of beetroot juice and novel beetroot-enriched bread products in normotensive male subjects. Br J Nutr. 2012 Mar 14:1-9. View Abstract
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Beetroot for Brain Health
Beetroot for Brain Health Beetroot juice may enhance blood flow to the brain, researchers report in the journal Oxide: Biology and Chemistry.
The study included 14 adults who were at least 70 years old. The participants ate either a low-nitrate breakfast or high-nitrate breakfast that included 16 ounces of beetroot juice for two days. The participants then switched treatment groups for another two days.
After the participants consumed beetroot juice, MRI scans showed that blood flow significantly improved in the white matter of the front lobes, an area that has been linked to dementia.
However, additional research in a larger sample size is needed to confirm these early findings.
Other human studies have tested the effects of beet on blood pressure, blood sugar and cholesterol levels. However, results have been mixed. Early evidence suggests that it may also be beneficial for inflammation of the abdomen and pelvic walls (called toxic peritonitis). More research is needed to determine if beet is effective for any medical condition.
- Natural Standard: The Authority on Integrative Medicine. www.naturalstandard.com
- Presley TD, Morgan AR, Bechtold E, et al. Acute effect of a high nitrate diet on brain perfusion in older adults. Nitric Oxide. 2010 Oct 15. View Abstract
Source : Natural Standard
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