Any idea why they need love to live. like do they need it like protein?

like us we need meat to live because of the iron we need in it for our brains and body to work right without it can lead to many things i don't want to list off how badly it can get.

like is love and emoinc act like that as a food?

and if so can there be a hope of making artificial substitute for? like making it into a candy like so they can feed of that?

4089649 We all need love to survive, baby!

BTW, headcannon approaching. Take cover if required.

Most animals, including humans, benefit from positive social interaction. There's some chemicals involved there, but I don't know which ones. It's entirely possible Changelings just had this go into overdrive, and it'd act like a drug. Technically, I don't think you can literally 'feed' off love. Protein and calories need to come from somewhere, and I'm pretty sure love doesn't fit that particular bill. I reckon they still need to eat.

Either that, or magic. But this is 'science' in Equestria, so...

4089664 wheil anything well do like why do they need it for casting spells or they need it like some kind of blood in away lacking that part in them to make it on there own.

4089719 Uh... what?

If I'm not much mistaken, love and similar emotions produce endorphins that make us happy. I'm simply theorizing that as they get loved, Changelings might produce a similar chemical that makes them particularly happy about themselves. As for why, well, that's a whole 'nother theory.

4089736 mmmm this may take longer than i think it is. oh wheil as the old saying go "Rome was not build in a day"

4089649 When I think of how changelings live off of love, I think of it in the same way vampire bats live off of blood.

To meet their energy needs, vampire bats need to drink about an ounce of blood at every meal, meaning they consume half their body weight during each 20 to 30 minute feeding session. Their bodies have adapted to lighten that load, and their stomach lining rapidly absorbs much of the blood’s water content and sends it to the kidneys so it can be excreted. The bats can process their meal so quickly that they may begin disposing of it before they’re even finished with it, and start urinating just a few minutes into the feeding.

Vampires are known to share meals with each other. Mother bats regurgitate previously-drunk blood for their offspring until the babies are old enough to hunt on their own. Other related bats and even unrelated ones have also been observed puking blood up for one another in a reciprocal arrangement. If a bat can’t find a meal one night, one of its roost-mates may share some of its meal. In the future, the bat who was fed is highly likely to return the favor. If it cheats, or takes a blood donation without ever giving back, it may find that it gets the cold shoulder the next time it needs help.

Vampire bats have a few different tools for finding their food. They have well-developed senses of smell and, despite bats’ reputation, keen eyesight. They’ve also got heat-seeking faces—their wrinkly, leaf shaped noses are loaded with nerves that are, in turn, loaded with proteins that are sensitive to the infrared radiation given off by warm-blooded animals. They also have finely-tuned hearing and specialized neurons that react only to the sound of breathing. They can even distinguish the breathing sounds made by different individuals, and may be able to remember the unique sonic components of an individual animal’s breathing, allowing them to return to the same reliable source of blood night after night.

Animals that are adventurous eaters learn to avoid potentially toxic foods through trial and error. They try something new, get sick, and then avoid those flavors in the future. Vampire bats appear to have lost their sense of taste aversion, though. In experiments, biologists have given vampire bats and their fruit- and insect-eating cousins treats seasoned with different, unfamiliar flavors, and then induced vomiting. At their next few meals, the bats were given the choice between normal food and food flavored with the same seasonings from before. While the other bats avoided the flavors they associated with getting sick after the first meal, the vampires dug in to both flavored and unflavored blood. The researchers think that the vampires either lost the ability to make these associations because their diet doesn’t present a variety of flavors and it wasn’t needed, or maybe that they had to lose it early on in their blood-drinking history to make the diet viable.

So, if it takes 100 bats 15 days at 30 minutes/day (7.5 hours) to finish off a whole cow (~1,000 lbs), it would take them only about 4.5 minutes to draw one pint of human blood...

4089649 First, I follow the idea that changelings feed off emotion in general, not just love. Love just has a higher "energy density" than other emotions. Now for the headcannon. I believe that when creatures (ponies, griffons, etc.) generate magic fields when they feel emotions. This isn't really spellcasting, it's more like how brains generate detectable electrical fields when they are in use. Changelings don't actually feed off the emotion, instead they leach magical energy from the fields generated by emotion.
Changelings don't actually need to feed off emotions to survive, they can live just fine without it. However, they can't generate magical energy on their own, just like how most predators can't synthesize all amino actions. In order to be able to use magic, changelings must leach magical energy from others who already have it. Just my thoughts

4089649 My own head canon? It supplies some level of energy to their body, specificity filling the roll of sugars meaning sweet things like bite sized apple fritters don't particularly taste all that good. It also doubles up as a means to amplify their magic, being derived from an motional source which in the MLP universe where emotions seem to augment someone's emotional abilities, such as Sombra reviling in the fear of his subjects and the effect friendship being so strong it is directly equated to magic.

However they still have physical bodies with a larger verity of needs the least of all is protein to maintain that body. So like other creatures 'love starvation' would not necessarily mean death but leave them week and vulnerable to diseases like malnutrition in one aspect of the diet of other creatures would.

For the sake of sustaining any large group the ability to transfer love to other changelings in some way is essential. As such I think they would regurgitate it as a liquid which could be further artificially refined and mixed into drinks or cooked with to add flavour and nutrition to the meals of those who might not leave more isolated parts of changeling society or settlements.

As for artificial creation? Perhaps indirectly, that is, an artificial mechanism like the crystal heart that could passively absorb and redistribute the specific stuff of magic .

However, again, this is all head canon. It's your own prerogative how you choose to explain the exact workings of a piece of fiction.

4089649

This is just mine headcanon, so take it with a grain of salt:

Emotion powers magic. Friendship is magic, Windigos and Sirens gain strength from strife, Changelings get strength from love. We know that ponies eat plants and Sirens eat sailors and tacos, and Windigos, Ponies, Sirens, and Changelings are made of matter, so I figure that all need to eat food. I do not know whether without the emotions powering their magic, windigos, sirens, and changeling will simply loose their magic, but be healthy, or whether the sirens, windigos, and changelings die without emotional energy.

4089649 Maybe, since everything we know in equestria seems to have some sort of (at least) implied love, and we know that love is it's own magic. Since everything has it in their own way, maybe it is necessary for life to exist. This could be backed up by the fact that when Tirek drained all of the magic everything just sorta'... well, died. Went bland and lifeless.

If Changelings lived without the magic of love and friendship, then they would need to get it from somewhere, right? Or else they too might grow dull and lifeless. sad and feeling like they're without purpose. Maybe eventually die. It's a bit far fetched, but it's one theory.