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Orange Juice or Vitamin C?
By AngryToxicologist | April 25, 2007
It’s been too long a wait for someone to do a study like this. In the wake of the large study that found that vitamin supplements are not helpful and some may be harmful, we have a simple study that should have been done long ago to determine if it’s the fruit and veggies or the anti-oxidants that are beneficial.
Let’s back up here. Vitamin supplements haven’t really been shown to effect actual health outcomes in large studies. Vitamin C has the best evidence going for it, but even that’s shaky. We just took the supplements (me included) because, logically, they should work to reduce oxidative stress. Not so surprisingly, the media took off with these speculations and it became the conventional wisdom. Surprisingly, science never really challenged this conventional wisdom until recently.
This study looked at whether there was a difference between Orange Juice (they used blood oranges), Vitamin C alone, or sugar water in protecting against oxidative damage. The authors had participants take one of the three drinks and took blood samples every hour for 8 hrs and then at 24 hrs. The blood samples where treated with hydrogen peroxide (a strong oxidizer) and the DNA damage to mononuclear blood cells was measured. Starting at 3 hrs and up to at least 24 hrs after drinking, the orange juice protected the cells while the vitamin C drink and sugar water had no effect in the study. Something else is going on with the orange juice that can’t be reduced to just vitamin C. Much more needs to be done but this is a great start (it would be nice if someone could do a bridging study using navel oranges or similar; they are all citrus sinensis but different hybrids, I think). The big question remaining in my mind is where the media coverage is.
Well, now we know you can’t get out of eating right with a pill. It doesn’t work with losing weight and it doesn’t work for getting nutrients. The good news is that 1) you don’t have to worry about what pills you should be taking and 2) OJ is not only really good for you, it’s tasty too.
PS This is the last day that you can give the FDA comment on the proposed change to allow chocolate to be made without cocoa butter, which is pretty essential, and instead with other vegatable fats. In other words, something that’s not chocolate will be able to be labeled chocolate. If you don’t want to be bamboozled into buying the next Mockolate, go to Don’t Mess With Our Chocolate to learn more and how to comment.
Topics: food, scientific study |
April 25th, 2007 at 12:57 pm
Interesting.
Of course, since they used blood oranges, I have to wonder how much this applies to regular oranges, which I suspect have a somewhat different nutrient profile. (They certainly don’t taste the same.)
What they didn’t (apparently) test is what most consumers use–pasteurized fresh or frozen orange juice. Since heat kills Vitamin C (and perhaps other things in the OJ), would this processed OJ have the same effect?
April 25th, 2007 at 2:58 pm
The amount of Vitamin C in pasturized OJ is about 20% less than fresh. This takes an 8 oz glass from ~170% daily value to ~135%. But as the study shows, it’s not really the vitamin C, or at least not alone. So your point leads to an even more complex question: what does pasteurization do the unknown factors that reduce oxidative damage?
May 4th, 2007 at 7:12 am
Something else is going on with the orange juice that can’t be reduced to just vitamin C. Much more needs to be done but this is a great start (it would be nice if someone could do a bridging
That may well be:
Glutathione, the granddaddy of endogenous antioxidants. So maintain your selenium levels, and your sulphur proteins (cruciferous veges)
42
Limonene, a monoterpene nutrient, foundin grapefruit and orange juice, inhibits tumour formation by stimulating the gene for glutathione S-trasferase. Citrus pulp and the white of the orange are rich in a family of phytochemicals called glucarates.
Genetic Nutritioneering: How You Can Modify Inherited Traits and Live a Longer, Healthier life
May 10th, 2007 at 8:13 am
[…] function couldn’t be shown in vivo. Sounds a lot like the Vitamin C pill vs O.J. issue (here, if you hadn’t seen it), […]
May 10th, 2007 at 12:09 pm
I’ve also read (”Twinkie, Deconstructed…” http://www.twinkiedeconstructed.com/Twinkiewebsite/Welcome.html) vitamin production can be a very caustic process. Personally, I try to avoid food with added vitamins (very, very hard to do) and natural flavors. The latter is a different argument, but ends in the same place: Eat quality, whole food prepared at home, and when you eat out go to reputable restaurants, which mostly eliminates your favorite chain.
PS The FDA has moved the date to submit comments to June 25th.
May 11th, 2007 at 12:37 pm
Since Vitamin C is destroyed by pasteurization, wouldn’t the vitamin C in pasteurized OJ just be vitamins (thus not really any good). The whole thing is pasteurization kills the bad stuff, you didn’t think it would harm the good stuff as well? Guess you just get the illusion of eating cake. Oh well fresh squeezed OJ tastes so much better anyway.
May 16th, 2007 at 7:10 pm
Suggested reading for the uneducated:
1) Ascorbate: The Science of Vitamin C, Steve Hickey, Hilary Roberts
2) The Healing Factor: “Vitamin C” Against Disease, Irwin Stone
3) Cancer and Vitamin C: A Discussion of the Nature, Causes, Prevention, and Treatment of Cancer With Special Reference to the Value of Vitamin C, Ewan Cameron, Linus Pauling
May 22nd, 2007 at 11:09 pm
Orange juice as most people drink it is a very processed food, not really all that healthy and much too high in sugar (especially the way people toss it back now). Commercial OJ isn’t even squeezed like home squeezed OJ. The whole orange goes into the vat. Yuck. IMO, OJ is pretty close to sugar water. A fresh orange, on the other hand, is a far better choice than OJ for lots of reasons.
June 14th, 2007 at 2:59 pm
30 years ago in a food science class I was shown two photos that were labeled as being from an electron microscope. One image was of synthetic vitamin C and the other was natural vitamin C. The natural vitamin C was apparently blurred, and the text explained that this was because the chemical seemed to “resonate” or vibrate. No similar resonation was apparent in the synthetic chemical. I’d be interested in your comments on this, especially on whether it might explain the apparent differences in efficacy between natural and synthetic or even highly processed natural vitamins.
June 15th, 2007 at 10:50 pm
Ok, Ok I get it now hahahaha. Thanks for the good post. I am getting there heh