Everything2 medical disclaimer
Yes, it's real and no, it is not the fear of dead (or undead) horses, or other equines.1
"Death is inevitable.
Tomato sauce is a choice."
Lauren-Rae Dodd
One of the cibophobias, mortuusequusphobia is a specific phobia, an anxiety disorder, characterized by the irrational fear, aversion, repulsion, revulsion, and/or loathing of tomato ketchup, it's very specific trigger food. Sufferers may experience anxiety, nausea, or other physical symptoms2 when confronted with ketchup, most often by sight or smell, or even the thought of it. Can be treated with cognitive behavioral therapy, systemic desensitization, exposure therapy or hypnotherapy. Medications may also sometimes be prescribed to help people manage their feelings of anxiety or, worse, panic attacks3.
Note that food phobias can sometimes be related to past traumatic experiences or other underlying psychological issues. The fear is disproportionate to any real danger, causes significant stress and disruption to one's life, and has lasted for at least six months. Sufferers may experience difficulties in maintaining social relationships, showing up to work, or performing other activities such as grocery shopping or dining out. Avoidant behaviors may become even more extreme in some individuals.
Also, it probably doesn't help that the color red stimulates faster heartbeats and breathing, either, but that's a minor, non-clinical observation.
Personally, I just don't like ketchup as a condiment, except with onion rings, cooked onto meatloaf, or a few select fast food hamburgers; completely do not understand its use on egg (or breakfast dishes or macaroni and cheese; plus there are way tastier things to put on French fries and hot dogs.
Footnotes:
1Mortuusequusphobia is named from the Australian version of Cockey rhyming slang, where dead horse refers to red sauce.
2Constant worrying, difficulty concentrating, fatigue, irritability, muscle tension, restlessness
3Symptoms include: shortness of breath, shaking, sweating, hot flashes, feeling faint, dizziness, chest tightness, tachycardia, nausea, a sense of impending doom.
Sources:
https://thetab.com/uk/northumbria/2015/01/25/im-scared-tomato-sauce-dying-5273
https://saraichinwag.com/fear-of-ketchup-mortuusequusphobia
https://her.ie/food/12-things-people-fear-tomato-ketchup-can-relate-302315
https://slangsensei.com/dead-horse-australian-slang/
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