What's the deal with tomatoes supressing testosterone?

[Brundle-Fly]

I've never seen anyone talk about it so I assume it is not a well know issue.

Check out this study: http://jn.nutrition.org/cgi/content/...ct/136/11/2813

Serum Testosterone Is Reduced Following Short-Term Phytofluene, Lycopene, or Tomato Powder Consumption in F344 Rats1
Jessica K. Campbell, Chad K. Stroud, Manabu T. Nakamura, Mary Ann Lila and John W. Erdman, Jr.

Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801

Elevated serum androgens are associated with increased prostate cancer risk. Tomato consumption is also associated with reduced prostate cancer incidence, and the primary tomato carotenoid, lycopene, may modulate androgen activation in the prostate, yet little is known about other tomato carotenoids. To evaluate interrelations between phytofluene, lycopene, or tomato powder consumption and androgen status, 8-wk?old male F344 rats (fed a control AIN 93G diet) were castrated or sham-operated and subsequently provided with daily oral supplementation of phytofluene or lycopene (~0.7 mg/d) or fed a 10% tomato powder supplemented diet (AIN 93G) for 4 d. Sham-operated rats provided with either phytofluene, lycopene, or tomato powder had ~40?50% lower serum testosterone concentrations than the sham-operated, control-fed group. Tissue and serum phytofluene and lycopene concentrations were greater in castrated rats than in sham-operated rats, which may have been due in part to a decrease of hepatic CYP 3A1 mRNA expression and benzyloxyresorufin-O-dealkylase activity. Some changes in prostatic and testicular steroidogenic enzyme mRNA expression were found; in particular, prostate 17?-hydroxysteroid dehydrogenase 4 mRNA expression in castrated rats fed lycopene or tomato powder was 1.7-fold that of the sham-operated, control-fed group. Modest changes in mRNA expression of steroidogenic enzymes with short-term carotenoid intake may alter the flux of androgen synthesis to less potent compounds. Overall, results illustrate that short-term intake of tomato carotenoids significantly alters androgen status, which may partially be a mechanism by which tomato intake reduces prostate cancer risk.



Obviously the effects would only be temporary but who wants to tolerate a 40-50% reduction in testosterone for the sake of some tomatoes?

[gsolo]

Obviously the effects would only be temporary but who wants to tolerate a 40-50% reduction in testosterone for the sake of some tomatoes?

It should be pretty obvious. The rats do. That's why they ate the tomatoes

[Brundle-Fly]

It should be pretty obvious. The rats do. That's why they ate the tomatoes

They don't know better.

I'm wondering if tomatoe sauce made from green tomatoes would work (serious).. Anyone? Correct me me if I'm wrong but lycopene only exists in red pigmented fruit/vegies. I think this is true with bell peppers. Don't know about phytofluene.

[Bodom X]

What about ketchup?

[Brundle-Fly]

What about ketchup?

It would be the same story. Not only that, but any fruite/vegie that is red is gonna contain lycopene, from what I've read.

Knowlege is a burden, but I'd rather know.


Also, on a sidenote, if you were a caveman that had never seen a tomatoe, and you found a red tomatoe and a green tomatoe, you'd probably be more inclined to take the green one as red (in nature) is usually a warning that indicates poison. "Hey, you eat me and I'll reduce you testosterone levels and therefore your fertility so there'll be less of you people to eat me". Ok, maybe that's going a bit far.

[nathanbailey]

i cant remember where i read it but doesnt cooking the red tomatoes make them.. not so bad for you? like almost no difference?

[in10city]

Read the full-text. Look at the doses in terms of the rodent's body weight. Translate that equivalent human doses and get back to me.

Posting abstracts that you don't properly interpret are meaningless.

[JustLost]

Read the full-text. Look at the doses in terms of the rodent's body weight. Translate that equivalent human doses and get back to me.

Posting abstracts that you don't properly interpret are meaningless.

This times 10,000.

"You must spread some reputation around before..."

[Brundle-Fly]

Read the full-text. Look at the doses in terms of the rodent's body weight. Translate that equivalent human doses and get back to me.

Posting abstracts that you don't properly interpret are meaningless.

Ok, let's say an 8 week old rat weighs 250g.. An equivalent human dose of phytofluene or lycopene might be 210mg/daily.

100g tomatoes has ~2.5mg of lycopene
100g tomato paste has ~30mg
100g tomato powder has ~45mg

Phytofluene, I don't know.

Now knowing that, it would seem there is no issue with eating whole tomatoes but I would avoid dishes that require a lot of tomato paste... I have a pizza recipe, nothing unusual about it, which I could easily eat on my own, that requires 170g tomato paste (one can), and I'm sure others would have more. Such a pizza, consuming one per day for four days (as per study), might set you back ~10%. Not much, but you wouldn't want it if you could avoid it. Then there's the question of a possible cumulative effect..

This is all assuming that the effect is based on the dose and not an on/off type of deal. Anyone have an idea of the chances it isn't?

At least my mind is now rested about whole tomatoes, so thanks.

[ThickAsABrick]

Stop sweating the small stuff.

Tomatoes kick ass.

[Brundle-Fly]

Stop sweating the small stuff.

Tomatoes kick ass.

They do, but think about this.. If I had a supplement that increased testosterone by 10%, I'd be a very rich man. So a 10% decrease is nothing to be sneezed at.

[ThickAsABrick]

I don't eat anything unless it's value is beyond approach. The slightest question-mark and it's out until proven innocent.

Wow, your life sucks.

[Brundle-Fly]

Wow, your life sucks.

Not really, I get my highs from things other than food.

[Brundle-Fly]

Also, I was reading that lycopene accumulates in the testes more than anywhere else in the human body. I don't want anything accumulating in my balls unless it's good for them.

[tweaked17]

Well, if this is true (and applicable to humans), now we know the likely reason lycopene prevents prostate cancer.

Great.. how many threads are we gonna see on this now?

[in10city]

Well, if this is true (and applicable to humans), now we know the likely reason lycopene prevents prostate cancer.

Great.. how many threads are we gonna see on this now?

It would probably really hit home for people to find out that their EVOO has an equivalent ibuprofen dose. Bye-bye mussles.

That's minutiae and a lack of perspective for you.

[ThickAsABrick]

I just ate a tomato on my sandwich for lunch and afterwards I started crying for no reason and asking co-workers if my suit makes me look fat.

They said no, but I don't believe them! *sobs*

[Brundle-Fly]

Well, if this is true (and applicable to humans), now we know the likely reason lycopene prevents prostate cancer.

Exactly. Whenever I hear or read about things reducing the risk of prostate cancer my first thought is that it's probably because it reduces testosterone, but the masses automatically hail these discoveries.

I read a study in my research of this that recommended lycopene should be injected into meat as a preservative and to add colour. Sure.. reduces the risk of prostate cancer, it's natural compound, so why not.

[Brundle-Fly]

I just ate a tomato on my sandwich for lunch and afterwards I started crying for no reason and asking co-workers if my suit makes me look fat.

They said no, but I don't believe them! *sobs*

Do you buy supplements? I'm sure you do. Creatine, ZMA, B6, whatever. For what?

If I offered you a way to increase your testosterone by any amount, 1% or 10%, that cost nothing, you'd snap it up, anyone would. Well I am offering you that, in a 'round about way, by suggesting you take a good look at what you eat. Food is a fuel.

Also, if you don't think diet has an impact, just look at how effeminate Asian/Indian people generally are. Look at what they eat. Everyone should know about soy by now. By the way do you eat it? Of course not, because you know better, but it seems like tomatoes might be just as bad. The research I've read suggests ~2-3% decrease in androgen status froma soy based diet, so we all avoid it like the plague. How's this any different? Did you know that certain ingredients in curry can induce increases in prolactin in the order of ten fold? Who wants that.

[tweaked17]

I just ate a tomato on my sandwich for lunch and afterwards I started crying for no reason and asking co-workers if my suit makes me look fat.

They said no, but I don't believe them! *sobs*

lmao

Exactly. Whenever I hear or read about things reducing the risk of prostate cancer my first thought is that it's probably because it reduces testosterone, but the masses automatically hail these discoveries.

That's a broad generalization that you don't need to make.

Do you buy supplements? I'm sure you do. Creatine, ZMA, B6, whatever. For what?

If I offered you a way to increase your testosterone by any amount, 1% or 10%, that cost nothing, you'd snap it up, anyone would. Well I am offering you that, in a 'round about way, by suggesting you take a good look at what you eat. Food is a fuel.

Also, if you don't think diet has an impact, just look at how effeminate Asian/Indian people generally are. Look at what they eat. Everyone should know about soy by now. By the way do you eat it? Of course not, because you know better, but it seems like tomatoes might be just as bad. The research I've read suggests ~2-3% decrease in androgen status froma soy based diet, so we all avoid it like the plague. How's this any different? Did you know that certain ingredients in curry can induce increases in prolactin in the order of ten fold? Who wants that.

The problem is, you can't just immediately translate all research to humans. If you could find some evidence that this applies to humans, then we'd be getting somewhere.

Rats are generally good models, but their metabolism does not directly mirror ours. Many enzymes, genes (& their expression), and processes differ in ways that can negate certain research conclusions.

Personally, I eat a LOT of tomato products. Two years ago when I had my testosterone checked on my bloodwork, it was between 800-900 ng/dl. I'm not worried.

Even if this were true and relevant, it wouldn't be enough for me to stop eating tomatoes. I friggin love em.

[Opies]

Eating a tomato isn't going to effect your gains.... plus tomatoes are ****ing great for you.

[LS2Stew]

I'm not eating tomatoes from now on. Who else is in?

[ThickAsABrick]

Do you buy supplements?

No, actually.

Not even shakes these days.

[wave_length]

Completely irrelevant, won't have any significant influence on body composition IMO.

[LS2Stew]

Completely irrelevant, won't have any significant influence on body composition IMO.

That's head in the sand style behaviour I'm afraid.

[JustLost]

I'm not eating tomatoes from now on. Who else is in?

Tomatoes are the only think I still eat. Everything else causes diabetes or cancer.

[wave_length]

That's head in the sand style behaviour I'm afraid.

Well I'm waiting for a study that proves negative effect on body composition of humans. In the meantime, I'll keep eating tomatoes, because they are tasty.

[LS2Stew]

Well I'm waiting for a study that proves negative effect on body composition of humans. In the meantime, I'll keep eating tomatoes, because they are tasty.

Another person whose stats suggest he eats too many tomatoes.

[wave_length]

Another person whose stats suggest he eats too many tomatoes.

You think I would blow up without them?

[rendermatt]

Ugh, they say they are good for you and promote T now they're bad! Whats the deal?