Antioxidant activity of blueberry fruit is impaired by association with milk

[al-209]

This from the Journal of Free Radical Biology & Medicine

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Abstract
The antioxidant properties of dietary phenolics are believed to be reduced in vivo because of their affinity for proteins. In this study we assessed the bioavailability of phenolics and the in vivo plasma antioxidant capacity after the consumption of blueberries (Vaccinium corymbosum L.) with and without milk. In a crossover design, 11 healthy human volunteers consumed either (a) 200 g of blueberries plus 200 ml of water or (b) 200 g of blueberries plus 200 ml of whole milk. Venous samples were collected at baseline and at 1, 2, and 5 h postconsumption. Ingestion of blueberries increased plasma levels of reducing and chain-breaking potential (+ 6.1%, p < 0.001; + 11.1%, p < 0.05) and enhanced plasma concentrations of caffeic and ferulic acid. When blueberries and milk were ingested there was no increase in plasma antioxidant capacity. There was a reduction in the peak plasma concentrations of caffeic and ferulic acid (− 49.7%, p < 0.001, and − 19.8%, p < 0.05, respectively) as well as the overall absorption (AUC) of caffeic acid (p < 0.001). The ingestion of blueberries in association with milk, thus, impairs the in vivo antioxidant properties of blueberries and reduces the absorption of caffeic acid.

Aint getting $31.50 out my pocket for the full document just yet, so my questions are:

Does this apply to Casein, Whey or all proteins? I have heard of phenols from tea binding to casein, is this the same process?

Does this apply to all antioxidants or just those specific to blueberries?

Like for instance if one took a green powder with whey only, would any AO effect be nullified as above or would removal of casein fraction allow the body to utilise the antioxidants?

How would the same apply with say Brown Rice protein?


Dont want to think that all the whey and blueberry smoothies ive had have been money down the pan...

[Ripped Barbarian]

If you put grape seed extract (high in polyphenols) in your mouth you'll notice that it coagulates the mucous in your mouth (hence giving the 'dry' taste)

I'm pretty sure it has an affinity to most proteins.

At the end of the day the antioxidants are over-rated, once you understand the abilities and techniques of your own antioxidant systems you'll know where your money is better spent.

[sendos]

RapidShare: 1-CLICK Web hosting - Easy Filehosting

theres the full article if you want it.

[ryandj2]

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If you put grape seed extract (high in polyphenols) in your mouth you'll notice that it coagulates the mucous in your mouth (hence giving the 'dry' taste)

I'm pretty sure it has an affinity to most proteins.

At the end of the day the antioxidants are over-rated, once you understand the abilities and techniques of your own antioxidant systems you'll know where your money is better spent.

They are very over-rated! the body has perfectly good mechanisms for clearing up oxidants and free radicals in the body, its just a load of bunkum to sell "super foods" and the like. I am sure that there have been numerous studies showing that supplementation with antioxidants do not make you any healthier...this blog gives a bit of information:

Are antioxidants overrated? An M.D.’s Journey into Natural Healing

[al-209]

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RapidShare: 1-CLICK Web hosting - Easy Filehosting

theres the full article if you want it.

Thanks sendos, but having trouble downloading it. Any chance of emailing it?

[sendos]

Yeah no worries, post your e-mail up and i'll remove the post afterwards.

[al-209]

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They are very over-rated! the body has perfectly good mechanisms for clearing up oxidants and free radicals in the body, its just a load of bunkum to sell "super foods" and the like. I am sure that there have been numerous studies showing that supplementation with antioxidants do not make you any healthier...this blog gives a bit of information:

Are antioxidants overrated? An M.D.’s Journey into Natural Healing

Interesting Ryandj2, but im not trying to cure cancer with bluberries. Regardless of how over hyped they may or may not be, there are beneficial compounds in blueberries and other fruits / veg that im probably better ingesting than not. Or would you disagree?? NU would disagree, of that im sure..

[ryandj2]

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Interesting Ryandj2, but im not trying to cure cancer with bluberries. Regardless of how over hyped they may or may not be, there are beneficial compounds in blueberries and other fruits / veg that im probably better ingesting than not. Or would you disagree?? NU would disagree, of that im sure..

I would certainly agree that eating a mixture of fruit and veg is beneficial, and I do include them in my every day eating.

Its the superfood and antioxidant-rich labelling of foods which I am cynical about - it is (in my opinion) a marketing ploy. In most cases, it seems to me that foods are called "superfoods" with very limited evidence to justify it.

Anyway, I don't tend to eat blueberries for two reasons - they are very expensive, and the ones in the supermarkets at least are tasteless and very watery.

[Ripped Barbarian]

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Interesting Ryandj2, but im not trying to cure cancer with bluberries. Regardless of how over hyped they may or may not be, there are beneficial compounds in blueberries and other fruits / veg that im probably better ingesting than not. Or would you disagree?? NU would disagree, of that im sure..

Hormetic effects are the main benefit from phytochemicals, this is how the antioxidants 'work' (because they actually have an oxidative stress modifying effect) ....same as exercise.
There are vitamins and minerals in plant foods of course but these are quite low intake from the small mass of high phytochemical foods.

Best bet, as usual, is to have your balanced diet with fruit and veg and you're fine.
My overall point that having fruit and veg/extracts for their antioxidant content is near irrelevant, look for induced effects from the food or antioxidant vitamin content.

[Weaves]

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NU would disagree, of that im sure..

Banter