The fascinating connection between humans and carotenoids
- Created on Sunday, 28 February 2021 04:07
Carotenoids are pigments, produced by plants, that occur as yellow, red, and orange. They serve as sunscreens to the plant, preventing ultra-violet damage, and they do that for us too when we consume them. And they provide other protective effects. But, are they essential nutrients? The answer is: yes and no.
Lutein, which is yellow, certainly is an essential nutrient. Without it, the retinal macula (which literally means yellow spot) would succumb to ultraviolet damage very quickly. So, if vision matters to you, you need lutein. And lutein does good things in your arteries and elsewhere too. But, it’s in your eyes that it’s really crucial. There is another yellow carotenoid that goes along with it, zeaxanthin. But from this point on, I’ll just refer to lutein, though I mean both.
Lutein occurs in yellow fruits and vegetables, but, it is just as abundant in green leafy vegetables. You don’t see it in the green leaf because the chlorophyll covers it up. But, when the green leaves die in the fall, the chlorophyll breaks down rapidly, exposing the other pigments that were there all along, hence: fall colors.
So, how did people get lutein in ancient times? And remember: they didn’t know they needed it. They got it from whatever green and yellow vegetables they ate and yellow fruits. As far as animal foods go, the yolk of an egg has lutein, and there is also some in milk which gets concentrated in butter if the cows are grass-fed. Of course, I’m not recommending those foods. But, just knowing that lutein occurs in green leaves, which grow practically everywhere, makes me realize that humans have always had access to lutein.
But, what about the red carotenoid lycopene? It’s not nearly as well distributed as lutein. It occurs in red foods, but not all red foods are red from lycopene. For instance, strawberries and cherries aren’t red from lycopene. And there are very small amounts of lycopene in non-red foods. For instance, asparagus has a little bit of lycopene, but it isn’t much.
So, the modern and widely available foods with the highest lycopene content are tomatoes, watermelon, and red grapefruit. Reddish varieties of papaya have it too, but it depends how red they are. Red guavas actually have the most, but I don’t consider them to be widely available, do you? It’s not like you can go into any supermarket and find red guavas. Red cabbage has a little bit of lycopene, but not much, despite being red.
The point is that when you compare the availability of lutein and lycopene, there is no comparison. Lutein is much more widely distributed.
But, let’s go back to those main food sources of lycopene in the modern diet: tomatoes, watermelon, and red grapefruit.
Ruby red grapefruit was developed at Texas A&M University for commercial production in Texas in 1929. Some pink varieties came earlier, but not much earlier. The white grapefruit goes back to the 19th century, but it doesn’t have lycopene.
Watermelon is native to Africa, and it as been grown for 5000 years. But, the original watermelon had no lycopene at all. It had pale green flesh and was immensely bitter. Selective breeding created the watermelon we know of today. So, for most of human existence, watermelon was not a source of lycopene.
Tomatoes are natïve to Southern Mexico and Western South America, essentially the Aztec lands. They weren’t red at first either, and they didn’t begin to spread outside of that area until after Columbus.
So, there were probably billions of people who lived their whole lives with little or no lycopene. And that tells me that lycopene is not an essential nutrient. Lutein is, but lycopene isn’t. It doesn’t mean it’s not useful and beneficial, but it isn’t essential. There is no distinct deficiency disease resulting from not getting lycopene.
But, don’t get me wrong: I am a big fan of lycopene, and I make a point of eating it. I eat watermelon all year long; partly because I like it; but also because I know about the lycopene. Or course, I eat tomatoes all year long too. And I eat Texas Ruby Red grapefruit for as long as they are in season, which is from October to April. I have all three of those foods in my house right now, and it’s not uncommon for me to ingest all three on a single day. I did today.
The effect that lycopene has on the prostate is what appeals to me the most. There is a ton of research showing that lycopene lowers the risk of prostate cancer. It lowers the absolute risk of it, and it also lowers the risk of developing aggressive prostate cancer. That is significant because the non-aggressive form of prostate cancer is not very problematic at all. Millions of men get it without even knowing it. It never causes them any problem or any symptom. And treating it aggressively is probably more beneficial to the health of the medical industry than it is to the men.
I’m 70, and the only thing that would cause me to consider having anything done to my prostate is if I couldn’t urinate. Obviously, I would have to do something then. But, as long as I can urinate freely and I’m not in pain, I am not messing with my prostate, and you have my word about that.
Am I saying that treating prostate cancer is a racket? Yes, that’s what I’m saying. But, it’s not entirely the fault of doctors. Some men freak out if they’re told that they have some cancer cells in their prostate. Me, I wouldn’t freak out. Of course, no one has ever told me that. But, hypothetically, if someone did, I would not freak out. They say that 80 to 90 percent of men are going to get some cancer cells in their prostate before they die- if they live long enough. So, why should I freak out about it?
But naturally, I’d rather not get prostate cancer, and loading up on lycopene foods is something I do proactively to prevent it.
Just think: here we are in 2021, and there are people who deliberately avoid eating plant foods. They shun them. There are even doctors who are doing that. It's incredible. How could anybody be that stupid?
I haven’t mentioned beta-carotene yet, which is the other major carotenoid, and it, of course, is orange. Like lutein, it is widely distributed in plants. Is it essential? If you rely on it for Vitamin A it is. Remember that pre-formed Vitamin A does not occur in plants. But, even if you eat animal foods that have pre-formed Vitamin A, such as cod liver, it would still be beneficial to get some beta-carotene. Fortunately, it is very easy to do.
But, what a fascinating thing that these pigments which make plants colorable and attractive and protect them from oxidative damage, including ultraviolet damage, do the same thing for us. Eat the rainbow diet, meaning, lots of colorful fruits and vegetables. That’s some solid advice. I recommend it, and I do it.