Monday, February 22, 2010

Is Orange Juice With Pulp Better For You?

All you have to do to understand the complex slurry of nutrients in your average piece of fruit is watch any of the countless documentaries about food being produced. You can watch The Future of Food or Food Inc., or read some random book about diet and learn about pectin, fiber, sugar, and the extra calories burned by eating raw food. So this raises an obvious question for the American breakfast eater: is OJ with pulp better for us?

It's not an easy question to answer. According to Tropicana, with pulp or without, the nutrition facts for orange juice are identical. But as we all know, the nutrition facts that companies are required to print are completely inadequate — if for no other reason than we still don't fully understand the way our body digests food. For example, it would be nigh-on impossible to get fat on raw apples, but you could easily pack on the pounds with apple juice or pan-seared apples.

Also, it just seems obvious that there has to be something in that pulp. It can't just be nothing. So what the hell is it? Well, scientifically, they're vesicles. Specialized cells that do nothing but store juice. The membrane of those cells is what comprises the pulp.


Picture stolen from Ciprex


As you can see from the diagram, those cells only make up about 2.7% of the total volume of the orange, so whatever they're made of, it doesn't comprise much. The vast majority of what is in an orange is in the juice. Unless you count the peel, which no one eats. Except for weirdos.

As with a lot of nutritional things, if the information is identical, we have to turn to scientific research for some kind of quantifiable benefit. Lucky for us, we have precisely that!

Orange pulp improves antioxidant status and suppresses lipid peroxidation in orchidectomized male rats

Nutrition, Volume 23, Issues 7-8, July-August 2007, Pages 617-621

Abstract:
Objective- Oxidative stress is linked to an increased incidence of cardiovascular disease in men. The objective of this research was to delineate whether daily consumption of orange pulp (OP) modifies antioxidant status and decreases cardiovascular risk factors in orchidectomized rats.

Methods- In the present study, 45 1-y-old male rats were randomized to a sham-control group (n = 9) and an orchidectomized group (n = 36). The orchidectomized group was equally divided among the following five treatments: orchidectomy (ORX), ORX + 2.5% OP, ORX + 5% OP, and ORX + 10% OP.

One hundred twenty days after the study began, all rats were sacrificed and plasma was harvested for its antioxidant status, C-reactive protein (CRP), lipid profile, and indices of peroxidation. Superoxide dismutase (SOD) and catalase activities in the liver were also monitored.

Results- Orchidectomy decreased (P < 0.05) plasma levels of antioxidant, SOD, catalase, and CRP and increased (P < 0.05) plasma levels of malondialdehyde, nitrite, and lipid profile compared with the sham-control group. In contrast to ORX, ORX + OP increased (P < 0.05) plasma antioxidant, dose-dependently increased (P < 0.05) SOD and catalase, decreased (P < 0.05) plasma malondialdehyde, nitrite, cholesterol, and triacylglycerol concentrations in the liver; and had no effect (P > 0.1) on plasma CRP or lipid profiles.

Conclusion- The beneficial effect of eating an orange is demonstrated by the increasing antioxidant status and by the decreasing peroxidation independent of plasma triacylglycerol, cholesterol, or CRP concentrations.


So it IS better for you to keep the pulp in the OJ... but for some unknown reason. Whatever the hell pulp is can be turned into fiber and other things for food alteration, but it's not fiber when we get it, nor does it affect the nutrition label.

Pulp contains a lot of flavonoids. In fact in your average orange, nearly all of the flavonoids are contained in the pulp. And flavonoids don't show up on any label, but our body does something with them, so is there any benefit to consuming them. As this study shows, the flavonoids do not have a direct effect on the body, but instead seem to stimulate the body's own waste-removal systems, which pumps more of the "bad stuff" out of our system. That somewhat jives with what we read in the previous journal entry.

So, still, it seems that we can be at least somewhat confident in the belief that OJ with pulp is better than without, but it is a very mild and indirect effect. If your diet is otherwise healthy and balanced, drinking pulp-free OJ, if that's your predilection, is no worse than drinking OJ that's practically a solid.

But is eating an orange better than the juice? Considering that diagram, and seeing that what we actually eat in an orange is primarily juice anyhow, what's the huge benefit to eating the fruit? I think that our own behavior has more to do with this than anything. An 8oz glass of OJ requires upwards of five oranges. A person can easily bang back 8oz of juice, and likely more. But eat five oranges in a sitting? Very few people do that. The process just naturally results in fewer calories.

I also think that the simple process of digesting results in fewer net calories in an ounce-for-ounce comparison. Even though there is pulp in OJ, it's been heavily machined. Much of the energy that would have been expended by our jaws and stomachs in processing the food has already been done, meaning more easy calories. Much of the raw food movement is predicated heavily on this idea, but I suspect, and the scientific evidence indicates, that this is a small effect.

Still, I think the conclusion to be reached is that the difference between OJ with and without pulp is very small and, if anything, indirect. You can achieve it by simply having a good, all-around diet. The difference between an actual orange and juice is nothing more than calories. So if you watch your calories around the OJ, eat, drink, it's whatever you feel like.

UPDATE 6/14/2010:

Previously, I had said that there is no difference in taste between OJ with or without pulp. That was apparently incorrect. I had never noticed before, but a recent taste test of juices showed pretty conclusively that OJ with pulp is lower on both sourness and bitterness. The differences are small, but noticeable. If you strongly prefer OJ without pulp, you're not sacrificing much.

BUT, if you want juice with absolutely fantastic flavor, pick up a bottle of Orchid Island, which came in first in that same taste test. You can buy it branded as Dave's own OJ at most Dave's Markets in Rhode Island. They don't keep it near the ordinary OJ, they usually store it in that gourmet juice section of the produce aisle. Is Orchid Island worth twice the price? Amazingly, yeah. It is. It tastes significantly better than any of the major brands. It's a truly delicious juice.

10 comments:

Stan Mrak said...

If you knew the full truth about how orange juice is made, you would realize how silly this debate is.

http://www.antioxidants-for-health-and-longevity.com/orange-juice-facts.html

Aaron MC said...

Hi Stan,

Thanks a lot for the link.

I read through the page and, not to seem a know-it-all dick, but it's pretty wrong.

As an overarching criticism, he doesn't cite any research, studies, or even magazine articles to support his statements. He just makes inflammatory accusations against the OJ industry.

He gets the part about fiber attenuating sugar absorption correct, but talks about a link between fruit juice and fructose to negative health effects.

Again, he cites no studies, so I Looked up my own. He's correct about a link between fructose and negative health effects, but the only studies I could find focused not on juices, but drinks artificially sweetened, like soda. I even found studies linked on the Wikipedia page that say that fructose is good for diabetics and for controlling the glycemic response to meals.

The only link to obesity and fructose was a study done on mice, which is a very tenuous link to humans. The stronger study about triglyceride levels showed a strong link between a diet with no fructose and one where 17% of calories were gained through fructose.

http://www.ncbi.nlm.nih.gov/pubmed/11063439

The link was found only in men. Women showed no negative effect to a high-fructose diet. So if we have men and assume a 2,000 calorie-per-day diet, that's 340 calories per day from fructose. That works out to about 24-27 oz. of OJ. But wait! OJ is only 50% fructose sugar, so we need to double those consumption numbers. 680 calories per day from OJ to reach the experiment.

A person could drink two whole pint of OJ every morning and not reach that level. And if the man eats a greater-than 2000kcal daily diet, he could ingest even more fructose.

A study that showed a link between both sexes,

http://www.sciencedaily.com/releases/2009/02/090212161819.htm

Only researched people who were already obese AND insulin resistant. This study can hardly be generalized, however useful it might be for obese health.

Another study showed more positive effects for fructose in comparison to glucose:

http://care.diabetesjournals.org/content/30/6/1406.abstract

And that study specifically mentions OJ in the abstract.

That's another issue. He seems to group OJ manufacturers into a large, nebulous group of menacing companies. He seems to subscribe to the thesis of a recent book, "Squeezed: What You Don't Know About Orange Juice." And part of this lack menace is a lack of transparency, which isn't true. Tropicana has appeared for a tour on the History Channel's show, Modern Marvels.

He talks about ethyl butyrate seemingly for no other reason than to name-drop a chemical to make the whole mess sound even MORE menacing, without mentioning that the chemical is harmless and only results in a orange-y aroma. The rest of the flavor packs is derived from orange oils extracted from the peel.

And much like "Squeezed," he can only make the process sound terrible. He can't make any statements about it being bad or dangerous, because it's not. De-aerating the OJ preserves it, but does not remove its "essence." Why it has a negative effect on the juice is unknown to me, but also the author of the page and the book.

Aaron MC said...

It could be that de-aeration prevents volatile compounds from aeroslizing, thus neutralizing the smell. And, taste being a combination of taste buds and smell, this effects the flavor. This would explain the addition of the ethyl butyrate. The taste buds for OJ may require oxidation reactions that rely on plentiful oxygen in the juice.

Is all of this chemical manipulation deceptive? Perhaps. It's true, the straw stuck in an orange is pretty far from accurate, but, duh! If you're that gullible, you've got bigger problems than orange juice.

Advertising is advertising. For example, I know that I am, in fact, not family when I go to The Olive Garden. Am I getting up in self-righteous arms over the ads? No. Any rational person knows that the OJ they buy has, at the very least, been pasteurized, which negates the fresh-squeezed image right there.

In the end, it doesn't matter. The end result is good-tasting orange juice that is pretty good for you.

Finally, his rule of thumb about fresh OJ isn't terribly accurate, even for his own purposes. Most OJ's say to consume within a week of opening, and brands like Tropicana, Simply Orange, and Florida's Natural usually have pull dates no more than 45 days in the future.

And then, if all of that didn't do enough damage to his credibility, he tries to sell us juice on the bottom of the article.

I would take the whole page with a huge grain of salt.

Stan Mrak said...

Don't look to nutritional studies to prove anything. It's easy to find contradictions, much easier than getting any consensus!

Back in 2005, Dr. John Ioannidis, an epidemiologist at Ioannina School of Medicine, Greece, showed that there is less than a 50 percent chance that the results of any randomly chosen scientific paper will be true.

Prestigious journals boast that they are very selective, and turn down the vast majority of papers that are submitted to them. The assumption is that they therefore publish only the best scientific work.

But Dr. Ioannidis' study of 49 papers in leading journals, which had been cited by more than 1,000 other scientists — in other words, well-regarded research — showed that within only a few years, almost a third of the papers had been refuted by other studies.

Making matters worse, the "hotter" the field, the greater the competition, and the more likely that published research in top journals will be proven wrong.

Aaron MC said...

Certainly an accurate statement. Skepticism must be taken into account in all areas of research, even journal entries. But, does that mean that his meta-analysis has only a 50% likelihood of being correct? Ahh, an the joys of an infinite regress.

For anyone interested in that article, they can read a write up at New Scientist here:

http://www.newscientist.com/article/dn7915--most-scientific-papers-are-probably-wrong.html

It's easy to find contradictions in all areas of research. Things that are widely regarded as true, now, were once highly dubious. Einstein's theory of relativity, quantum physics, or the dangers of smoking and trans fats.

Still, on a general level, even poorly crafted experiments will at least have a seed of continued research. So, for example, OJ being healthy for you may not be correct, but OJ being healthy for you in certain circumstances and for certain people may be. It's up to the peer-reviewed community to take up the research, continue it, and keep other researchers in check. As such, a single study may be nothing to write home about, but multiple studies begin to show a strong link.

And on a specific level, OJ is certainly not a "hot" field. Food research may be, and even high-fructose additives in regards to soda and processed foods, but not OJ.

Moreover, that criticism could also be applied to the statements that the author made about health links to OJ and fructose. Much of what supports what he said is supported in only a few entries at most. The only concrete statement he made was about sugar absorption and fiber.

Anonymous said...

I suppose then that there's a 50% chance that Dr. John Ioannidis' research/statement is also wrong.

Aaron MC said...

Anonymous,

At this point, I think that there's a 50% chance that I don't exist.

chance said...

ive been wondering about this pulp is better great maybe now i can convince my parents to stop buying no oulp oj, thank you!

Monsef Kharbouch said...

I love orange juice , & thank you for share with us The Benefit of Vitamin C

Anonymous said...

I have just discovered Dr. Ray Peat. Google him, and read his articles. It will blow your mind. He says the reason you do not want the pulp is because the pulp goes into the intestine as a waste product and feeds the bacteria there. He does love the orange juice though. He says a quart a day would be a good amount to drink.