Citrus Phytochemicals Have Anti-Diabetic Effects
Citrus foods are tart and delicious. They also contain numerous phytochemicals that will modify our metabolism.
This is especially true for three special phytochemicals – naringin, naringenin and neohesperidin. These three polyphenols – also called flavonoids – are among others that have been found to affect our metabolism by interfering with inflammatory pathways.
A recent review of research on these flavonoids from the University of Queensland in Australia found that naringin and naringenin can help prevent diabetes and its accompanying conditions – hypertension and obesity.
The mechanisms of action is of particular interest to these researchers. Further investigation has led to the reality that these flavonoids prevent oxidation and thus reduce inflammation.
Naringin and neohesperidin reduce fasting blood sugar
Reducing the rush of blood sugar is an important component of reducing diabetes. IN 2012, researchers from China’s State Agriculture Ministry and Zhejiang University determined that two ingredients commonly found in many citrus fruits, naringin and neohesperidin, will effectively reduce blood sugar.
The study tested the two citrus constituents using human liver cells. The scientists found that the two natural compounds increase the uptake of glucose among the cells.
This study confirms previous research that pointed to the possibility that these citrus constituents may be helpful for reduce blood sugar for those with or at risk for type 2 diabetes and suffer from poor glucose control and/or heightened glucose tolerance. Other research has found these compounds also regulate liver enzymes phosphoenolpyruvate carboxykinase and glucose-6-phosphatase – helping glucose uptake regulation and increasing liver efficiency.
The researchers extracted the two flavonoids from the Chinese citrus fruit called Huyou (Citrus changshanensis). This citrus, as well as others such as Grapefruit and related species – has been used as an anti-diabetic agent in Traditional Chinese Medicine, Ayurveda and other traditional Asian medicines.
What is naringin, naringenin and neohesperidin?
Naringenin, naringin and neohesperidin compounds are found throughout the fleshy part of most citrus fruits. This includes the juice sacs and the segments. Another Chinese study found that the Huyou peel contained the highest naringin and neohesperidin content.
Several other citrus fruits contain naringin and neohesperidin. This doesn’t mean that orange juice necessarily contains naringin and neohesperidin. A 2000 study from the Citrus Research and Education Center tested a number of orange juices using liquid chromatography. The analysis found that the two 100% orange juice samples tested contained neither naringin nor neohesperidin. However, juice samples that contained orange juice together with small amounts of grapefruit juice, sour orange (Citrus aurantium) juice and K-Early citrus juice did contain naringin and neohesperidin.
Other research has determined that the common sweet orange (Citrus sinensis) will typically contain naringin, but very small amounts, and will typically not contain neohesperidin. Sour oranges (Citrus aurantium) – especially when picked early, will contain considerable amounts of naringin and neohesperidin. Mandarin oranges (Citrus Reticulata) are also good sources for both naringin and neohesperidin. Grapefruit contains naringin and neohesperidin, but its neohesperidin content is typically smaller.
What about lemons and limes?
Lemons and limes typically do not contain either compound in lieu of their hesperidin content, but a few species – such as the Bergamot – will contain naringin and possibly small amounts of neohesperidin.
In addition to its anti-diabetic properties, naringen has been found in laboratory studies to be neuro-protective (helps protect brain tissue). It appears to protect against the effects of 3-nitropropionic acid, which has been found to be one of the primary agents that produce nerve damage in Huntington’s disease and other nerve disorders.
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