Metabolic syndrome is the name for a group of conditions that increase the risk for heart disease and other health problems. The syndrome is diagnosed when a person has at least three of the five following conditions:
- A large waistline. This is called abdominal,
or central, obesity. For men, risk increases for a waist circumference
greater than 40 inches. For women, it’s 35 inches.
- High triglyceride levels.
Triglycerides are a type of fat in the blood. Fasting levels of 150
mg/dL or higher are considered a risk factor for metabolic syndrome.
- Low HDL cholesterol. HDL is the “good”
cholesterol that seems to protect against heart disease. For men, risk
increases with an HDL of less than 40 mg/dL. For women, elevated risk is
associated with an HDL of less than 50 mg/dL.
- High blood pressure. For men and
women, the recommended blood pressure cut-off is 130/85 mg/dL. Elevation
of the top, bottom or both numbers increases risk.
- High blood glucose. Glucose is the form of sugar the body uses for energy. Elevated blood sugar levels may be an indication of insulin resistance or diabetes. Fasting blood glucose levels of 100 mg/dL or higher are considered to be a risk factor for metabolic syndrome.
The National Heart, Lung and Blood Institute estimates nearly 25 percent of Americans (47 million people) have metabolic syndrome. People with metabolic syndrome are twice as likely to develop heart disease and five times more likely to develop diabetes. Metabolic syndrome also increases the risk for peripheral artery disease and stroke.
Kudzu for Health?
Kudzu is an invasive type of vine that is commonly seen in the southeastern U.S. It was first introduced here by Japanese gardeners during the 1876 Centennial Exposition in Philadelphia. During the Great Depression, the Soil Conservation Service paid people to plant kudzu to control soil erosion.
Once kudzu took root, experts began to question their decision to grow the vine. The climate in the Southeastern U.S. provided ideal growing conditions for the plant. The kudzu vines are hard to control and can grow as much as one foot a day during summer months, or up to 60 feet a year. Researchers estimate kudzu now covers more than 7 million acres of land in the South. The vine climbs and covers poles and buildings. It can quickly cover an entire tree and block out sunlight. J. Michael Wyss, Ph.D., Neuroscientist with the University of Alabama at Birmingham, says a kudzu vine can kill an oak tree in one year.
Agricultural experts are now looking for ways to safely curb kudzu growth and eliminate the pesky, invasive vines. Other scientists, though, say the plant may have some redeeming qualities. Wyss says kudzu contains important healthy substances, called isoflavones. One particularly important isoflavone is puerarin, found only in kudzu. In fact, it’s the most abundant isoflavone in the plant.
The Chinese have used puerarin as an alternative medicine for centuries. So, researchers decided to investigate the effects of kudzu in animals. Female rats were given an extract made from kudzu root for two months. Another group of rats were fed a standard diet. At the end of the study, the rats given the kudzu extract had lower cholesterol, lower blood pressure, and lower blood sugar and insulin levels than the rats that ate the control diet. According to Wyss, only a very small amount of kudzu root extract was needed to achieve these results.
The study suggests that kudzu may be an effective alternative treatment that could be used in conjunction with traditional drugs to control insulin and cholesterol levels, and ultimately lower a patient’s risk for metabolic syndrome. In some cases, doctors may be able to give patients lower doses of other drugs, reducing the chance for side effects from the medication and making medications more affordable.
Wyss says kudzu is available in some health food stores. However, the exact doses needed for humans are not yet known. Researchers need to understand how kudzu works and who may benefit from it the most before beginning human trials. The investigators only studied a kudzu root extract. If other parts of the plant are found to also be beneficial (like the leaves), it’s possible people may eat the plant like a salad to get health benefits. Another research study found kudzu root to be effective in protecting brain function in rats with blockages in the cerebral and carotid arteries.
American Heart Association, http://www.americanheart.org
National Heart, Lung and Blood Institute, http://www.nhlbi.nih.gov
For general information about kudzu: The University of Georgia Center for Invasive Species and Ecosystem Health, http://www.invasive.org/eastern/species/2425.html
Peng, Ning, et al., “Chronic Dietary Kudzu Isoflavones Improve Components of Metabolic Syndrome in Stroke-prone Spontaneously Hypertensive Rats,” Journal of Agriculture and Food Chemistry, August 26, 2009, Vol. 57, No. 16, pp. 7268-7273.
Reppert, Adam, et al., “Isolation of Radiolabeled Isoflavones from Kudzu (Pueraria lobata) Root Cultures,” Journal of Agriculture and Food Chemistry, September 10, 2008, Vol. 56, No. 17, pp. 7860-7865.
Zheng, P., et al., “Therapeutic Effect of Puerarin on Non-alcoholic Rat Fatty Liver by Improving Leptin Signal Transduction Through JAK2/STAT3 Pathways,” American Journal of Chinese Medicine, 2009, Vol. 37, No. 1, pp. 69-83.