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Par Dr Michael Murray, médecin naturopathe
One of the most powerful superfoods is the beet. Both the leaves and root are packed full of nutrients and phytochemicals. And modern research has uncovered remarkable health benefits, including improving cardiovascular health, strength, and stamina with beetroot juice consumption.1
Beetroot juice powder has emerged as a fantastic way to capture all the nutritional and health benefits of beet juice in a convenient and tastier manner. The purple-crimson color of beetroot juice powder is due to betalains, which include betacyanin, the primary pigment of beets.
Betalains are also the key phytochemical components responsible for many of the health benefits of beetroots.2 Yet, the biggest focus of beetroot supplementation has been its nitrate compounds.3
As in beetroot juice, nitrates in beetroot juice powder ultimately increase nitric oxide production by cells lining blood vessels. Nitric oxide is very important in improving blood flow, lowering blood pressure, and preventing the formation of blood clots. By increasing nitric oxide levels, beetroot juice powder improves blood flow, reduces blood pressure and clot formation, and improves blood fluidity (the blood becomes less viscous and, therefore, flows through blood vessels more easily).
In addition to dietary nitrate, beetroot's betalain components also increase the activity of an enzyme, endogenous nitric oxide synthetase (eNOS), that boosts nitric oxide levels irrespective of the nitrate component. This action is a key antiaging effect of beetroot juice powder as eNOS activity declines as a person ages.
The potential antiaging effects of beetroot juice powder are seen in a double-blind study in older subjects (ages 65 to 79). Both a single and daily dosage for two weeks of beetroot juice increased muscle speed and power significantly.
Two weeks of supplementation increased maximal knee extensor speed (Vmax) by 7% and power (Pmax) by 9% higher than baseline measurements. The authors of the study concluded, "The magnitudes of these improvements are sufficient to offset the decline resulting from a decade or more of aging…."4
Beetroot juice powder can enhance human physiology or body processes via several key mechanisms, like beetroot juice. The nitric oxide-boosting action of beetroot juice is an important aspect of its ability to boost blood flow, improve athletic performance, and even lower blood pressure. But it is another example of a fundamental, underlying effect of beetroot in promoting overall health. It is well-established in clinical studies in humans that beetroot juice supplementation can improve blood flow dynamics.2,3
The ability to improve blood flow extends throughout the body, including the brain, heart, kidneys, skin, and erectile tissue. The point is that delivering more blood and oxygen to cells is ultimately what beetroot juice powder provides, which generally leads to improved function in all cells, tissues, and organs. Collectively improving blood flow to all body tissues, beetroot juice powder becomes a whole-body tonic that helps improve overall health.2,3,5
Beetroot juice powder exerts additional health benefits based on research on its key components. And while it can be added to the long list of natural products that exert direct antioxidant action, even more, important is beetroot juice powder's ability to influence cell signaling pathways that activate the body's antioxidant system. Specifically, betalains activate Nrf2 (nuclear factor-erythroid 2-related factor 2), the main regulator of the body's response to cellular damage and inflammation. Nrf2 is a master conductor of the expression of hundreds of genes that promote the formation of many antioxidant/detoxifying enzymes and compounds (e.g., glutathione). Betalains enhance the expression of these cellular protectors and rejuvenators. By increasing Nrf2, beetroot juice powder promotes health on a very deep cellular level.2,3,6
Betalains also activate SIRT1, one of the body's chief sirtuins. Molecules are made famous in scientific circles for slowing down aging and helping to address obesity, blood sugar control, cognitive decline, and many other age-related disorders. Resveratrol is the most well-known SIRT1 activator. But betalains work to activate SIRT1 through a much different mechanism and appear to affect the Sirtuin network in much more powerful ways than resveratrol.6 Researchers are just beginning to explore this exciting path.
Much of the blood pressure-lowering effects of beetroot juice are attributed to its nitrate component, which is converted by oral bacteria into nitrite and absorbed into the body. The nitrite is subsequently converted into nitric oxide by the cells that line blood vessels throughout the body. Beetroot nitrate ingestion promotes lowering blood pressure via improved dilation and reduced blood vessel stiffness, thereby reducing the force (pressure) exerted against the blood vessels as the blood pulses through.
Although there are other dietary sources of nitrates, beets are considerably more effective in raising blood nitrite levels than eating a very high intake of other nitrate-rich foods or taking a nitrate salt supplement. The level of nitrate in the diet has minimal impact on plasma nitrate and nitrite, but beet juice consumption can significantly increase plasma nitrate and nitrite throughout the day.3,7
The clinical evidence for the blood pressure-lowering effect of beetroot juice has been shown in over 100 human clinical trials. In one of the first studies looking at beetroot juice and blood pressure, researchers at The London School of Medicine showed that drinking 16 ounces of fresh beet juice a day significantly reduced systolic (top number) and diastolic (bottom number) up to 10 mm Hg in healthy subjects.8 Beetroot juice lowered blood pressure within an hour, with a peak drop occurring 3 to 4 hours after ingestion. The peak time of reduction in blood pressure correlated with the appearance and peak levels of nitrite.
Since this initial study in 2008, over 100 additional clinical studies have evaluated the blood pressure-lowering effect of beetroot juice.9,10 The overall effect from pooled data in sufficient duration and dosage studies shows a more modest drop of 5 mm Hg of both the systolic and diastolic blood pressure. And while not a huge drop, this level of blood pressure reduction would cut the rate of strokes and heart attacks by about 10%. In terms of lives, that would mean about 1.5 million lives being saved each year.
In most of the studies with beetroot juice, the nitrate level in the product or the subject's blood was the key factor of effectiveness. The blood pressure lowering effect usually takes about two weeks as a single dose has a negligible effect. And the blood pressure-lowering effect of beetroot is enhanced if people are engaged in regular moderate-intensity aerobic exercise.11
There is some variation in the response to the blood pressure-lowering effects of beetroot, with advanced age and genetics being a key factor because of less activity (aging) or less expression (genetics) for eNOS. This enzyme converts nitrite to nitric oxide.12 Another cause of reduced effectiveness is insufficient oral or gut microorganisms that convert nitrate to nitrite.
And while the blood pressure-lowering effect of beetroot juice is important, the most consistent clinical finding of beetroot juice is in improving the function of the blood vessel lining, leading to improved blood flow. This action may be more important in the ability of beetroot juice powder to promote cardiovascular health.
There has been considerable scientific investigation on the effects of beetroot juice on exercise, muscle strength and stamina, and post-exercise recovery. A recent detailed systematic review of all clinical research in these applications concluded that beetroot juice supplementation was most effective for increasing exercise performance for those activities lasting between 2 to 10 minutes, and best results seem to be achieved when the beetroot juice supplementation was given at least 2.5 hours before exercise. It was also concluded that the use of an antiseptic mouthwash, or anything else that disrupts the oral microbiome, will disrupt the conversion of beetroot nitrates into nitrites to reduce the effectiveness of beetroot production with potential negative impacts on cardiovascular health and exercise performance. May decrease the effect of nitrate.
Beetroot juice can also enhance overall physical performance and heart functioning during exercise. For example, in a 2009 study, 12 male cyclists ingested 140 ml/day of concentrated beet juice or a placebo (nitrate-depleted beet juice) for 6 days. They were then crossed over to the other drink after a 14-day washout period.15 After supplementation on Day 6, subjects performed 60 minutes of submaximal cycling, followed by a 10-km time trial. Time-trial performance (953 vs. 965 seconds) and power output (294 vs. 288 watts) improved after the real beet juice compared with the placebo. In submaximal cycling, the use of oxygen (VO₂) was also lower with the real beet juice ingestion. What does all this data mean? In short, beet juice promotes increased physical stamina and performance. In athletic competitions, that may mean the difference between winning or losing.
Beetroot juice is particularly helpful in enhancing high-intensity exercise performance that involves explosive movements lasting less than 6 seconds like weightlifting or sprinting. Results from a systematic review showed that in 4 of the 10 sprint-type studies, beetroot juice supplementation improved sprint time and power output. In the weightlifting studies, 4 of the 10 studies showed improvements in the power and velocity of free-weight and isokinetic exercises.16
Beetroot juice may also boost exercise-related recovery and help with quicker recovery of strength and a reduction in post-exercise pain, inflammation, and muscle damage. Beetroot juice also prevents exercise-induced muscle damage (EIMD) according to a meta-analysis of six double-blind, controlled studies. EIMD results in decreased muscle strength, increased muscle soreness and swelling, and markers of inflammation in the blood. Pooled results showed that subjects consuming beetroot juice powder before accelerated isometric strength recovery 72 hours after exercise increased the pressure pain threshold within 48 hours.17,18
Since the active components of beetroot are heat sensitive, the best beetroot juice powders are produced without high heat. In this regard, beetroot juice powders that utilize the INFIDRI™ process stand above the rest. First, it is a beetroot juice powder designed to supply all the key components that clinical research has validated. Many beetroot powders on the market are ground-up beetroots that are dried in drums or spray-dried with high heat. The INFIDRI™ process is a gentle drying technology that utilizes targeted wavelengths of infrared light that remove water from beetroot juice without damaging the fragile beneficial compounds.
With dozens of positive human clinical studies with beetroot juice, there is some evidence for dosage levels needed to improve cardiovascular health, physical strength and tolerance, and recovery from exercise using beetroot juice powder. Most studies used daily dosages of beetroot juice between 70 and 250 ml, and the best results were seen when taking at least 140 ml of beetroot juice for more than 14 days. The dosage for beetroot juice powder should approximate this level. There is variation in quality in beetroot juice powders, and dosage will vary accordingly.
For a high-quality beetroot juice powder, such as California Gold's Organic Beetroot juice powder, 10 g (one tablespoon) is approximately equal to 100 ml of beetroot juice.
To simplify daily intake recommendations when using beetroot juice powder, for general health one tablespoon per day is sufficient, but for supporting blood pressure control and other targeted indications, a higher dosage of two tablespoons (20 grams) is recommended.
Beetroot juice powder is generally well-tolerated, and no side effects are seen at recommended intake levels. However, consuming beetroot juice powder, beets, or beet juice will often cause dark red or black-colored stools and red-tinted urine. Do not be alarmed. It is simply the red pigments in beetroot. It is a normal occurrence.
There are many ways to add beetroot juice powder to a person's diet if they want to enjoy all the great health benefits. Remember that mixing beetroot juice powder is a great way to add a little sweetness and more depth of flavor to all sorts of sweet and savory meals. Here are a few recipes with beetroot juice powder to get you started.
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Divide the mixture into 10 even balls.
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