human photosynthesis

If humans could human photosynthesise would we ever need to eat again?

I'm just wondering how possible the following sernarios would be

It may solve world hunger
Humans could heal wounds quickly from absorbing sunlight
More brain power
More physical endurance

How would we achieve this? DNA from plants and animals are so different.

Maybe i've already disprooved my own post here but a future that could do great feats like this would surely bring the human race into a brighter future.

It may be possible humans in the future won't need to eat or drink (Water effeciently recycled by a custom designed organ).

And due to renewable energy and a availabilty of resources every country in the world would be content, there would be few wars as they would have nothing to fight over as everything is renewable.

The only thing we may be concerned with in material wealth.

A bright future indeed, but now i've gone slightly off topic again , oh well

Plants don't rely 100% on sunlight - they need minerals etc from the soil (or in some rare cases other means).

We do require sunshine for our bodies to produce vitamin D (or is it B?).

reply to post by klain


Humans don't have anywhere near the surface area it would take to live off of sunlight. You'll note that plants tend to have a lot more surface area than humans (leaves, needles, etc.), and that they *don't move*. We've got a surface area to volume ratio comparable to some of the least nimble species of cactus out there. It works fine for stuff like those cacti, but we humans sometimes like to move every once in a while. Not to mention that sometimes we like to have a heart that's constantly using large amounts of energy to beat, and we sometimes like to have a brain that uses maybe 20W just to stay alive and ready to think.

You'll also notice that plants have roots, so they can absorb trace nutrients from the ground. We don't. We have to get a lot of essential chemicals from our food. We don't just eat for calories. Even if you grew a nice head of leafy foliage for hair, you'd still be vulnerable to scurvy. Of course, if we can put the code for chlorophyll in a person, we can also reactivate the genes that let us make vitamin C. But we need more than that. We need nitrogen compounds, several amino acids, several other vitamins, several trace minerals, and large quantities of water.

It is concieveable that we could produce most of the organic molecules we need in our bodies, with sufficient modification. Trace elements and water will always be needed though.

It wouldn't let you heal faster, be smarter, or have any more endurance. photosynthesis creates saccharides from sunlight, water, and carbon dioxide. And that's all it does. It would simply allow you to go some unknown (short) amount more time between eating. Assuming you aren't starving to death at the time, it will have no effect on your healing rate. Your blood sugar level isn't the major factor. Endurance is a factor of respiration. Assuming you aren't malnourished, it won't make a difference. Thought is based on brainpower, which again, would only be impacted if you were currently starving.

But since humans don't have very much surface area, and are quite massive and energy intense, being green with chlorophyll wouldn't make any significant difference. Even if the only downside is the social stigma from being the only green person on your block, it's probably not worth it.

That said, if you wanted to do it, it wouldn't be as hard as you suggest. Plant and animal DNA is identical in structure. Genes from plants will code for the same protein in an animal as it does in a plant. If you could isolate the part of a plant's DNA that codes for chloroplasts, the only hard part remaining would be putting it in human DNA so that it only expresses in skin cells. A challenge, certainly, because we don't know too much about gene expression, but I'd peg it as surmountable within a few decades.

There are some other problems with this idea. Photosynthesis costs water in multiple ways. In order to take in carbon dioxide, you need pores in your outer coating, which allows water to escape through evaporation. Desert plants have various ways of reducing this loss, but you'll notice they're even less nimble and lithe than regular plants. That and they're waxy all the time. Secondly, water is actually consumed during the photosynthesis reaction. No matter how efficient you are at keeping water inside your body, you'll be using water faster than without photosynthesis, because photosynthesis uses water. We also lose a lot of water to breathing.

Now one idea is to ditch the idea of using plant chlorophyll altogether, and build a custom set of genes that let you use carbon dioxide from the bloodstream, instead of from the air. That would be more science-intensive, and would probably take longer to implement, but at least your could have skin with a similar texture to normal human skin.

One more problem is that plant DNA does differ from ours in that it's got a lot more redundant copies and repair mechanisms. That and they don't have a real bloodstream equivalent. They're extremely resistant to getting cancer, and it's very survivable when it happens to plants. Humans don't have that luxury. We just aren't made for standing around in sun for days at a time. Skin cancer is a real concern.

I'm of the opinion that it could be done (given a few decades), but it would be far from the best use of genetic modification on humans. Wouldn't hurt to try, except maybe for the ostracization of the test subjects due to their inhuman skin color.

From my rough (and generous) calculations, if you receive full noon day sun on every inch of your body's surface area all the time, and you're photosynthesizing every incident photon, you'll be receiving just barely enough power to live on.

That's kind of an unrealistic scenario though.

[edit on 12-5-2008 by mdiinican]

Originally posted by Now_Then
Plants don't rely 100% on sunlight - they need minerals etc from the soil (or in some rare cases other means).

We do require sunshine for our bodies to produce vitamin D (or is it B?).

Vitimin d

Ok i know they don't use only sunlight, but neither do we

reply to post by mdiinican




Ok fair do's thanks for the post you have given me a lot to think about


Mod Note: Excessive Quoting – Please Review This Link


[edit on 12-5-2008 by Jbird]

Another thing to think about is that we do not need to take a biological approach to this.

Part of what I specialise in is a concept known as Biomimetics, which is taking inspiration from nature's designs and then using man-made materials and technologies to copy them.

Using the concept of photosynthesis- which may be distilled into the concept of mobile surfacial power generation, we could think up a system whereby a person's clothing is covered in nano-solar cells which generate power.

Now electricity and power requirements are vastly different to the biochemical requirements of humans, so we would still need to eat. But wouldnt it be cool to plug in your mobile or ipod into your shirt and get free charging power

reply to post by klain


Just on a side note - The mods will frown on quoting an entire post like that!

They just love to spank us mere members

reply to post by klain


An interesting though, klain.

Perhaps in the future, we shall be able to clone a gene into humans which gives us the ability to photosynthesize, and continue to eat as we are now.

I agree with the others that photosynthesis alone could cause problems, but a composite of the two digestive/respiration systems is food for thought...

For one thing, we'd have to be green, because photosynthesis requires chlorophyll.

In the light reactions, one molecule of the pigment chlorophyll absorbs one photon and loses one electron. This electron is passed to a modified form of chlorophyll called pheophytin, which passes the electron to a quinone molecule, allowing the start of a flow of electrons down an electron transport chain that leads to the ultimate reduction of NADP into NADPH. In addition, it serves to create a proton gradient across the chloroplast membrane; its dissipation is used by ATP Synthase for the concomitant synthesis of ATP. The chlorophyll molecule regains the lost electron by taking one from a water molecule through a process called photolysis, that releases oxygen gas.

en.wikipedia.org...

[edit on 2008/5/12 by GradyPhilpott]

Originally posted by Saurus
reply to post by klain

 

An interesting though, klain.

Perhaps in the future, we shall be able to clone a gene into humans which gives us the ability to photosynthesize, and continue to eat as we are now.

I agree with the others that photosynthesis alone could cause problems, but a composite of the two digestive/respiration systems is food for thought...

I was arguing under the assumption that you'd continue eating and drinking as normal. To me, it seems like it probably isn't worth being green and having oddly textured skin. Also: it probably isn't worth having everyone naked all the time.

Integrating some kind of solar powered system into clothes seems like a better idea to me, because then you'd be able to benefit from having them *While not naked*

reply to post by klain

My girlfriend tried to get me to drink a glass of chlorophyll yesterday (yes, it comes in powdered form). . . It was terrible! Human photosynthesis. . . It'll never happen.

'Nuff said. Blech!

Brilliant idea. I do hope scientists will look into this more. Even if we still required some other type of sustainance, it would still cut down on the food required.

Originally posted by clay2 baraka
reply to post by klain

 

My girlfriend tried to get me to drink a glass of chlorophyll yesterday (yes, it comes in powdered form). . . It was terrible! Human photosynthesis. . . It'll never happen.

'Nuff said. Blech!

I worked at Jamba Juice once, and they sold wheatgrass juice, which has a lot of chlorophyll in it. They made me drink some during job orientation. Tastes like grass smells. I've 'ad worse, but still. Wouldn't buy it.

There's no credible evidence for any health benefits from straight up eating chlorophyll. That is, after all, not what it's made for. Even Jamba Juice, which makes like two, three bucks an ounce on the stuff will only go so far as to say "Anecdotal evidence suggests health benefits.".

[edit on 12-5-2008 by mdiinican]

This was straight up chlorophyll. Again, Blech!

Wheat grass juice, while I was skeptical at first, actually didn't taste so bad. Grassy but sweet. As for the health benefits. Apparently drinking a shot gives you several servings of vegetables. Which is great for people like me who don't eat many veggies.

Back to the topic, however. I am not so sure I could find a algae colored person attractive. Not even if it was Kate Moss.

This is possibly the most intriguing topic I have read on the internet. Me and my friends have been discussing this topic for months now and we just dont understand how it isnt possible. Surely out there, there are cutting edge gene technologists investigating this as i type. My god what a world this would be!

p.s. I'm talking about human photosynthesis as a controlled energy source and a storage capacity enough to produce at least 500g of hexose sugars.

Also I've just realised that plants store sugars as starch don't they and cellulose whereas we store them as glycogen. Thoughts on this?

Dudes...

What you gys are talking about is called the ancient technique of "Sun Gazing"

It's pretty much the human form of photosynthesis and if you get good at it you dont have to eat ever agin. Look up a man named "Ratan Manek" he's like the modern day spokes-person for sungaing has been doing it since like 1995 and hasnt eaten since then.

There's also I remember a scientist(Dr Michael Werner) that learned how to do it....cant recall his name but he was doing scientific research into how this is possible with lab work and othe things.

Also here's a link to a pdf on the topic and how to train your body to just live off sun-light and air:

niejedzenie.info...

Oh and Nasa confirms it to be possible by studying an indian dude who did the same...."sun gazing"
www.8bm.com...


[edit on 25-6-2008 by dominicus]

[edit on 25-6-2008 by dominicus]

Originally posted by Anonymous ATS
This is possibly the most intriguing topic I have read on the internet. Me and my friends have been discussing this topic for months now and we just dont understand how it isnt possible. Surely out there, there are cutting edge gene technologists investigating this as i type. My god what a world this would be!

p.s. I'm talking about human photosynthesis as a controlled energy source and a storage capacity enough to produce at least 500g of hexose sugars.

Also I've just realised that plants store sugars as starch don't they and cellulose whereas we store them as glycogen. Thoughts on this?

This post was a post that just occoured to me, i'm afraid i'm not a scientist so I dont think I can answer but if theres anyone out there who can please do

Originally posted by dominicus
Dudes...

What you gys are talking about is called the ancient technique of "Sun Gazing"

It's pretty much the human form of photosynthesis and if you get good at it you dont have to eat ever agin. Look up a man named "Ratan Manek" he's like the modern day spokes-person for sungaing has been doing it since like 1995 and hasnt eaten since then.

There's also I remember a scientist(Dr Michael Werner) that learned how to do it....cant recall his name but he was doing scientific research into how this is possible with lab work and othe things.

Also here's a link to a pdf on the topic and how to train your body to just live off sun-light and air:

niejedzenie.info...

Oh and Nasa confirms it to be possible by studying an indian dude who did the same...."sun gazing"
www.8bm.com...


[edit on 25-6-2008 by dominicus]

[edit on 25-6-2008 by dominicus]

If this is possible shouldn't it be a world news story?

A world news story???? Hardly!!!!

This stuff is on the edge of science and too many of them(scientists) have no balls to tackle stuff on the edge.

"Sun Gazing" or living off of sun light used to be considered an occult phenomona and anything that has "occult" attached to it, scientists stay away from because of their reputations.

Thats why my hats off to Tesla cause he didnt give an ish what anyone said or thought about him. Fortunately there are still a handful of scientists who just dont give a crap.

There are countless other findings/inventions that just wont be published in major newspapers/scientific publications, why would this one surprise you???

Especially since only a few hundred people around the world have ever done sun gazing and lived off of sunlight.

Originally posted by klain
If humans could human photosynthesise would we ever need to eat again?

I'm just wondering how possible the following sernarios would be

It may solve world hunger
Humans could heal wounds quickly from absorbing sunlight
More brain power
More physical endurance

How would we achieve this? DNA from plants and animals are so different.

Maybe i've already disprooved my own post here but a future that could do great feats like this would surely bring the human race into a brighter future.

It may be possible humans in the future won't need to eat or drink (Water effeciently recycled by a custom designed organ).

And due to renewable energy and a availabilty of resources every country in the world would be content, there would be few wars as they would have nothing to fight over as everything is renewable.

The only thing we may be concerned with in material wealth.

A bright future indeed, but now i've gone slightly off topic again , oh well

You apparently aren't familiar with the fact that people DO live off the sun. The art of Sun Gazing is an ancient practice, and right now there are thousands of people who live off of pure sunlight. A man called HRM has not eaten food for many years, and there are thousands of others who have taken to his methods.

Go to this website to find out more:

Sun Gazing website