Beets can be a polarizing vegetable. Often found in the supermarket with long stems and some dirt, this root vegetable is not intuitive to prepare so people may avoid them altogether. Beets are known for their “earthy” flavor, caused by the compound geosmin. Beets can play a significant role in a well-balanced dietary pattern.
Beets belong to the chenopods botanical family, which also includes chard, spinach, and quinoa. They come in many varieties: the most common type of beets is the red beet, with the yellow beet variety coming in a close second. From the heart-shaped beetroot to the dark, leafy beet greens, the entire plant is edible. The root itself is high in unique phytonutrients, which have impressive anti-inflammatory and antioxidant activity. The roots also provide a blend of micronutrients that have been found to have a wide range of potential benefits, including methylation support, cardiovascular health, and cognitive benefits.
Phytochemicals in Beet Root1
The rich color found in beets is due mainly to the unique phytonutrient pigments called betalains, which are rare among vegetables and have been found to have many health benefits. The two basic betalains are betacyanins (includes betanins), which are deep red or violet in color, and betaxanthins, which are yellow. Dark red and purple beets are higher in betacyanins and golden yellow beets are higher in betaxanthins, lutein and other carotenoids. Beet greens are a rich source of the carotenoid phytonutrients lutein and zeaxanthin, both of which support eye health.
Studies have shown that the betalains and betanin present in beets have potent anti-inflammatory and antioxidant effects, and may also play a role in reducing the risk of oxidative stress and chronic inflammatory conditions, including cancer and arthritis. Specifically, the phytonutrient betanin has been shown to inhibit COX-2 inflammatory pathways, prominently involved in the pain-related inflammatory process. Betanin has also been shown to support healthy gene expression, which can protect against cancer. Betanin has been found to increase the action of Nrf2, an enzyme responsible for boosting the body’s endogenous antioxidant defenses, such as glutathione and other phase II detoxification enzymes. When Nrf2 is boosted, the body’s healthy detoxification pathways are supported and better able to modulate inflammation and reduce oxidative stress.
COX-2: Cyclooxygenase-2 (COX-2) is an enzyme that triggers the formation of prostaglandins, pro-inflammatory mediators that trigger inflammation in response to infection or injury. COX-2 is often responsible for the inflammatory cascade that causes pain and swelling in acute conditions and chronic inflammatory conditions, such as osteoarthritis and rheumatoid arthritis.
Nrf-2: Nuclear factor E2-related factor 2 (Nrf2) is a transcription factor that promotes the expression of genes that influence antioxidants and detoxification, including glutathione S-transferase A2 (GSTA2) and NADPH quinone oxidoreductase 1 (NQO1). Elevated levels of free radicals and reduced glutathione levels trigger the activation of Nrf2, and certain phytonutrients. When activated, Nrf2 increases the body’s antioxidant and detoxification defenses.
Glutathione: Glutathione is an important antioxidant and a major detoxification molecule in the body. It supports immune function and healthy phase I and II detoxification pathways and it protects cells against free radical damage. Glutathione is synthesized in the body from amino acids, yet some people may not produce enough endogenously.
Over 200 clinical conditions are related to oxidative stress, so beets and other high-antioxidant foods that can scavenge free radicals and reduce oxidative stress may have important effects on health and chronic disease prevention.
Practical tip: The phytonutrients in beets are sensitive to heat and can be significantly diminished after 15 minutes of cooking. Keep cooking times short to keep nutrient density high.
Dietary Nitrates, Nitric Oxide and Blood Flow2,3
Beets and beet juice are high in dietary nitrates, a compound that has been found to support blood vessel function and healthy blood flow. Also known as endothelial function, the mechanism has been shown to be protective against hypertension, atherosclerosis, cardiovascular disease, exercise induced oxidative stress, stomach ulcers, stroke, and cognitive changes. The nitrates found in beets differ from those found in processed meats and improve, rather than hinder, endothelial function (see text box below for more detail).4
When beets and other high-nitrate foods are consumed, symbiotic bacteria in the mouth convert nitrate into nitrite. Once in the stomach, nitrite reacts with stomach acid to produce nitrous acid, which breaks down to form nitric oxide (NO).5 This is referred to in scientific literature as the nitrate-nitrite-nitric oxide pathway. NO supports proper endothelial function and promotes healthy circulation. NO signals to the smooth muscle in blood vessel endothelium to dilate, or relax, to enhance blood flow. Beet juice specifically has been found to reduce hypertension, improve exercise performance and recovery, and enhance exercise tolerance through this NO pathway. Vasodilation is important to whole body health, as it allows the delivery of oxygenated blood, glucose, lipids and other nutrients to tissues throughout the body.6
In addition to cardiovascular health, supporting adequate blood flow and endothelial function is important to brain and cognitive health. Diminished NO availability occurs with age and can impair normal activity in the brain that is reliant on cerebral blood flow. Reduced blood flow to the brain has been implicated in several neurological disorders, including dementia and Alzheimer’s disease. Because beets and beet juice increase NO availability, they may improve cerebrovascular blood flow and support healthy cognitive function.7
Beets are among the foods highest in dietary nitrate. Beets, arugula, spinach and lettuce, increase NO availability in the body. The nitrates from beets are nearly 100% bioavailable, and eating vegetables rich in nitrates appears to be the best way to increase circulating NO.8
Not That Kind of Nitrate
“Nitrates and nitrites” automatically trigger thoughts of preservatives in processed and cured meats, which have been implicated in the development of colon and other cancers. While processed meats are certainly linked with increased risk of certain cancers, research has shown that nitrates from vegetables are not associated with any health risk and rather provide protective benefits. Researchers point out that nitrates from vegetables also include antioxidants, which may inhibit the formation of carcinogenic nitrosamines derived from nitrates and nitrites in processed meats.
Betaine, Methylation and More9
Beets are high in a micronutrient called betaine, also known as trimethylglycine, which serves several functions. It acts as a methyl donor, along with choline, folic acid, vitamin B12, and methionine. These micronutrients work together in a process called methylation, which is important to cellular health and replication. Specifically, methylation turns “on” or “off” genes to influence whether they are expressed or suppressed. Methylation is a key component of epigenetics, the process by which environmental factors like diet influence genetic expression. For this reason, beets are often included as a component of diets optimal for methylation.
Betaine is readily absorbed and may help to protect kidney, liver and heart health. It protects against methylation imbalances that can lead to elevated plasma homocysteine, dyslipidemia and fatty liver disease. High homocysteine levels may indicate poor methylation function, and can increase the risk for heart attack, stroke and coronary artery disease. Researchers have observed an inverse relationship between plasma betaine levels and homocysteine. In the liver, betaine may prevent or reduce the accumulation of fat in the liver, which may be protective against non-alcoholic fatty liver disease. In the kidneys, it can protect cells from high concentrations of urea and electrolytes, as well as modulate immune function in liver cells during times of stress by mediating TNF-a, phagocytosis, COX-2 and prostaglandin expression. In all cells, betaine helps regulate osmolality, hydration and volume, helping the body adapt to stressors. This type of osmotic function helps regulate red blood cell volume by influencing membrane activity. Some research suggests that diets high in methyl donor nutrients, like betaine and choline, can be protective against certain cancers, including breast cancer.10
Methylation is the transfer of one carbon methyl group (CH3) from one molecule to another that activates or deactivates the target molecule. Methylation is necessary for many functions, including: cell division, DNA and RNA synthesis and repair, epigenetic regulation of gene expression, neurotransmitter synthesis, detoxification, phospholipid synthesis, myelination of peripheral nerves and central nervous system development (neural tube formation).
Raw, juiced or roasted, this superfood offers a wealth of potential health benefits, courtesy of the unique antioxidants, phytochemicals and key nutrients found in beets.