Diets Rich in Polyphenols Decrease Oxidative Stress

A study just released in the American Journal of Clinical Nutrition by Annuzzi and coworkers demonstrated that diets naturally rich in polyphenols positively influenced fasting and postprandial triglycerides and reduced oxidative stress. These effects may contribute to explain the favorable association of dietary polyphenols with cardiovascular risk.

Read more:  http://dx.doi.org/10.3945/ajcn.113.073445





Increased Dietary Antioxidant Intake Associated With Improved Blood Pressure In Diabetic Individuals

A higher intake of dietary antioxidants measured as ORAC was associated with lower risks of hypertension. Read more… http://dx.doi.org/10.1038/jhh.2012.19





New Study Shows Positive Relationship of Polyphenols & All-Cause Mortality

A new study published in The Journal of Nutrition by Zamora-Ros and coworkers provides further data on the importance of dietary polyphenolic consumption and health outcomes. The current study evaluated the relationship total urinary polyphenol excretion and total dietary polyphenol intake and all-cause mortality during a 12 year period among an older adult population. Total urinary polyphenol excretion was analyzed using the Folin-Ciocalteu assay which is a chemistry assay based upon a measure of antioxidant reactive compounds in the urine. A total of 807 participants were followed for a period of 12 years.  Participants in the highest one third for total urinary polyphenols experienced a 30% lower all-cause mortality than those in the lowest one third. In an earlier study by this same research group, high total urinary polyphenols were associated with a reduction in both systolic and diastolic blood pressure and with the prevalence of hypertension. The authors point out that polyphenol biomarkers have several advantages over dietary data collected using self-report methods in that they provide an objective measure that is independent of the biases and errors associated with self-report methods. The highest tertile of dietary intake of polyphenols was equivalent to approximately 10,800 micromoles TE/day. The full manuscript is available using the following link:   http://dx.doi.org/10.3945/jn.113.177121





Ten Misconceptions about Antioxidants

“Owing to the polarity of views towards antioxidants, nutritional recommendation ranges from advice to increase antioxidant status in plasma to the notion that it is a useless measurement.”

Highlights:
• Opinions on antioxidants are highly polarized, leading to misunderstanding in the field.

• Specific antioxidants may have specific effects and side effects.

• With their pleiotropic modes of action, antioxidants should be considered bioactives

 

To Read More click on: http://www.sciencedirect.com/science/article/pii/S0165614713000989





Dietary Polyphenolics and Health; New review published discussing mechanisms of action beyond antioxidant effects

Read more here.





Review of Published data on Dietary Intake of Antioxidants (ORAC) and Health Outcomes Published

Read more:  http://dx.doi.org/10.5099/aj130200126





New Method Released to Determine In vivo Antioxidant Status

New Method Released to Determine In vivo Antioxidant StatusA nonfluorescent probe has been used which, after being oxidized by reactive oxygen species present in serum samples, was transformed into a form that emitted fluorescence. By quantifying the specific fluorescence, the scientists were able to measure the reactive oxygen species concentration which does not discriminate between the various free radicals found in the human body. Thus this assay can be very useful in quantifying total reactive oxygen species in vivo.

Read more:    http://dx.doi.org/10.5099/aj130200154





Issues of Equivalency in Determining Antioxidant Capacity?

Issues of Equivalency in Determining Antioxidant Capacity?

AOAC Stakeholder Panel on Strategic Foods Analytical Methods (SPSFAM) met in March 2013 to discuss if it was possible to establish equivalency between methods which use different principles to determine antioxidant capacity to allow for comparison of results? Data was presented to the panel demonstrating that it is not really possible to compare different methods because of the different chemistries involved with the different methods.

The “Standard Method Performance Requirements for in vitro Determination of Total Antioxidant Activity in Foods, Beverages, Food Ingredients, and Dietary Supplements” (AOAC SMPR 2011.011) has been revised removing the requirement for equivalency to be demonstrated. (Click here to review SMPR)





Protection from Oxidative Stress by Blueberry Antioxidants

Consumption of a practical amount (75g) of blueberries decreased serum markers of oxidative stress following consumption of a high carbohydrate meal. This is the first report that has demonstrated that increased serum antioxidant capacity is not attributable to the fructose or vitamin C content of blueberries. Read More: http://dx.doi.org/10.1017/s0007114512003650





ORAC Method First Action Paper Published

Manuscript just released entitled “Determination of Total Antioxidant Capacity by Oxygen Radical Absorbance Capacity (ORAC) Using Fluorescein as the Fluorescence Probe: First Action 2012.23” published in JOAC International.

An improved method for the measurement of oxygen radical absorbance capacity (ORAC) was developed and validated using fluorescein as a new fluorescence probe along with the peroxyl radical. The Expert Review Panel (ERP) on Strategic Foods Analytical Methods reviewed the method “Analytical Parameters of the ORACFL Assay” during the AOAC INTERNATIONAL Annual Meeting on October 2, 2012. After evaluating the data available, the ERP agreed that the method meets standard method performance requirements, as articulated by the Stakeholder Panel on Strategic Foods Analytical Methods (1). The ERP granted the method First Action status, applicable to the measure of total antioxidant capacity (AC) of foods. The ERP will monitor the ORACFL’s performance, and after about 2 years, will recommend the method to the Official Methods Board for Final Action if the assay is found to be suitable. This method provides the basis for the data in the ORAC database published on the web (http://oracdatabase.com)  Sufficient data have been derived on foods, making it possible to utilize it in determining dietary intakes of ORACFL and relate intake to health outcomes in several large epidemiology studies.  For more detail see the following link:

http://dx.doi.org/10.5740/jaoacint.13-175