Stevia (Stevia rebaudiana) is native to Paraguay, South America. Also known as sugarleaf or sweet leaf. Was discovered in 1887 by the Swiss botanist Moisés Santiago Bertoni. Added to the botanical archives in 1899. Stevia is used for health problems, and natives of Paraguay believe that it can help to treat diabetes, hypertension, heart disease, dental cavities, infections, heartburn and fatigue.
At first, the leaves of stevia were consumed fresh or dried but eventually scientists isolated the glycosides named rebaudioside and stevioside from its leaves that give stevia its sweet taste. Stevioside, is a natural sweetener extracted from leaves of Stevia rebaudiana Bertoni. Stevioside (a white crystalline compound) found in the Stevia rebaudiana of the plant is a natural plant sweetener with no calories and is 100-300 times sweeter than table sugar. Isosteviol and steviol are metabolic components of stevioside.
The first commercial stevia sweetening product in Japan was produced by the Japanese Morita Kagaku Kogyo Co. Ltd. in 1971. Stevioside, a natural glycoside isolated from the herb Stevia rebaudiana, has been commercialized as a non-caloric sweetener in Japan for a long time. Stevia sweetener products represent more than 40 % of the low-calorie sweetener market in Japan. The US banned stevia in the early 1990s unless labeled as a dietary supplement. however in 2008 it approved rebaudioside A extract as a food additive. In 2011, stevia was approved for use in the EU. Stevia is available as a sweetener in Europe, Japan, Malaysia, South Korea, Taiwan, Russia, Paraguay, Mexico, Columbia, Venezuela, Uruguay, Brazil, Argentina, Australia and New Zealand.
Stevioside is a natural glycoside isolated from the Stevia rebaudiana, which has showed blood pressure lowering activities. Several researches have suggested that stevioside acts as a typical systemic vasodilator. Some studies shown that taking 750-1500 mg per day of stevioside, decrease systolic blood pressure by 10-14 mmHg and diastolic blood pressure by 6-14 mmHg within 1 week of starting therapy. A study reported in the British Journal of Clinical Pharmacology in Sept 2000 looked at stevia’s use as an antihypertensive in 106 participant with hypertension. The study demonstrated that oral stevioside, was well-tolerated and effective in lowering blood pressure.
Stevia plant have been shown to inhibit hepatic gluconeogenesis and enhance insulin sensitivity in animal-based studies. A preliminary study suggests that 1000 mg daily of stevioside, might decrease blood sugar levels after meals by 18 percent in patients with type 2 diabetes. According to a study reported in The Brazilian Journal of Medical and Biological Research in 1986, stevia was found to reduce glucose levels. 1000 mg of stevioside has been taken with meals to reduce blood sugar in people with type 2 diabetes. Water extracts of 5 g of leaves have been used at 6-hour intervals for 3 days to enhance glucose tolerance.
Stevia Plant Side Effects
Some individuals who take stevioside can experience nausea, bloating, dizziness or muscle pain. This plant might cause an allergic reaction in people who are sensitive to the daisy family (Asteraceae compositae). Any drug containing lithium has the probability to interact with stevia. If you are taking psychiatric drug lithium, talk with your healthcare provider before using stevia products. Also, talk with your doctor before using stevia if you are taking diabetes drugs and antihypertensive drugs.
Stevia is safe to use. In the US, a purified component form of the plant is “generally recognized as safe” by the FDA and may be used as an artificial sweetener in foods and beverages. It has been designated a safe product by the Food and Drug Administration, based on the findings of using 1500 mg per day for 2 years. The World Health Organization’s Joint Expert Committee on Food Additives, in 2008, concluded that you can use between 0 mg and 4 mg per kg of body weight safely per day. The Food Standards Australia New Zealand performed a exhaustive risk evaluation prior to approving the addition of Stevia to the Australian food supply in 2008. Particularly examined any possible negative risk to diabetics and children and concluded “there are no public health and safety concerns for steviol glycosides when used as a food additive at the maximum levels proposed”.
Steviol and stevioside have been subjected to extensive genetic testing. The majority of the results show no evidence of genotoxic activity. Stevia plant has been used in Japan since 1970 and there have been no finding of toxicity or other adverse effects. One research during 2006 conducted by the WHO, demonstrated that the rebaudioside A derived from the stevia has no adverse effect on health, including an increase in the risk of cancers. A study reported in Food and Chemical Toxicology 2008; concluded that the use of stevia does not pose a risk of genetic damage or increased risk of cancer. According to a research reported in 2009 edition of Food and Chemical Toxicology, Dr. Lonnie Williams demonstrated rebaudioside A, did not have any genotoxic effects.
The Effect of Stevia on Infertility
In a study reported in 1985, researchers reported the potential of negative effects with stevia use on the male reproductive system. But, in 1999, researchers at “University of Chulalongkorn” gave large doses of stevia to both female and male hamsters to see if their fertility would be affected. As a result, there was no evidence of decreased fertility. A study in a 2006 edition of Southeast Asian Journal of Tropical Medicine and Public Health showed that stevia has not negative effect on the fertility of female rats. According to European Food Safety Authority (EFSA), there is no proof that stevia plant interferes with female or male reproductive system development and function.