1. If I said I was drunk on bread, you’d probably think I’d just had one too many pieces of focaccia. But for people with Auto-Brewery Syndrome, being drunk on bread—or any carb—is a reality. ABS causes carbohydrates to actually ferment in the stomach, producing ethanol, the ingredient in alcohol that makes people feel and act tipsy.

So how come most of us can hit the unlimited bread-sticks at Olive Garden without staggering out like it was a three-martini lunch? Well, first of all, it’s a very rare condition. A 2021 report found fewer than 100 cases reported worldwide since 1952. But also, it takes an extremely unbalanced microbiome in your gut to create the kind of environment that can turn carbs into ethanol. And it really is like being drunk—people with ABS who take a breathalyzer after eating carbs will fail. In fact, some people find out they have Auto-Brewery Syndrome when they fail a breathalyzer and know that they haven’t had any alcohol at all.

So, do these poor people have to do Keto for the rest of their lives? The good news is, most of the time, ABS is resolved with just one treatment. The treatment itself depends on what microbe doctors think is causing it—an antibiotic or antifungal medication may work; probiotics to help balance gut bacteria may also be prescribed. Some patients may relapse and need another round of treatments, and some may never find the right combination of things that works for them, meaning a low-carb diet may be in the cards for life.

Hi, I’m Erin McCarthy, editor in chief of Mental Floss, and this is The List Show. ABS is just the first super rare medical condition we’ll be discussing today. Let’s get started.

2. In 2008, Brad Pitt and Cate Blanchett starred in a David Fincher movie about a man who was born elderly and aged backward. Maybe you’ve read the F. Scott Fitzgerald story it was inspired by: The Curious Case of Benjamin Button.

Hutchinson-Gilford Progeria Syndrome is the real-life version of this disease; in fact, it’s sometimes called Benjamin Button disease. It’s not quite the same as the fictional illness, but you can see the similarities—instead of aging completely backward, old to young, a child with HGPS ages very quickly. The condition is caused when a specific gene makes an abnormal protein called progerin, which causes cells to break down more quickly than usual.

Outwardly, a child with HGPS has wrinkled, age-spotted skin; slow growth; hair loss; and stiff joints. Inside, they experience health issues we typically associate with older folks—bone loss, hardened arteries, even cataracts and arthritis. Although the fictional Benjamin Button dies as an infant at the age of 85, sadly, most children with progeria have fatal heart attacks or strokes in their teens. Luckily, HGPS is quite rare: It only occurs in 1 out of 4 million live births have it.

3. In Lewis Carroll’s Alice’s Adventures in Wonderland, when Alice eats a cake marked “Eat Me,” she quickly grows to be more than 9 feet tall—which is how some people with Alice in Wonderland Syndrome feel. They may also feel unusually small, or perceive other people and objects to be larger, smaller, farther, or closer than they really are. One young AIWS patient commonly perceived buildings growing taller and closing in on him. And in one very Alice-like incident, he reported that his fingers grew too big while he was trying to play chess; he was unable to grasp the pieces.

We don’t know quite what causes Alice In Wonderland Syndrome, although we are fairly certain it’s not cake. Certain cough medicines, specifically those containing dihydrocodeine or methylephedrine, have been reported to trigger symptoms. But according to the University of Nebraska Medical Center, other research suggests that underlying causes could include “strokes, brain tumors, aneurysms, viral infections, epilepsy, migraines, eye diseases,” and depression. Even Lyme Disease and H1N1 influenza have been suggested as culprits.

In short, there’s still a lot we don’t know about AIWS yet, and that’s largely because it’s so rare—from 1955 to 2016, only 200 cases required medical attention (though the condition might be underdiagnosed). It’s also notoriously hard to nail down because the symptoms are “fleeting,” as neuroscientist and AIWS expert Moheb Costandi describes it. The distortions typically last for a short period of time, making it difficult to get a brain scan during the episodes to further research what’s going on. This also makes it challenging to treat; in most cases, treatment is provided based on whatever doctors believe the underlying cause is, migraines or epilepsy, for example.

4. Imagine if you could climb the Burj Khalifa, jump from a plane at 25,000 feet, drive a motorcycle off of a cliff—all with no fear. OK, so I did just describe Tom Cruise. But there’s also a real medical condition called Urbach-Wiethe Disease where one of the side effects is the inability to feel fear. Urbach-Wiethe is a genetic disorder characterized by collagen deposits and thickened skin, resulting in papules on the face. It can also cause a hardening of brain tissue, which is where fear comes in—or, to be more accurate, doesn’t.

The hardening of the brain tissue means that the amygdala can become calcified. Located in the medial temporal lobe in front of the hippocampus, the amygdala is the part of our brains that helps us process emotions. We know that a damaged amygdala can prevent people from identifying fear in facial expressions—they simply aren’t able to recognize the emotion. But the long-term study of one patient with Urbach-Wiethe makes some researchers think that sometimes they can’t feel fear, either. 

Over a period of time, researchers at the University of Iowa observed an Urbach-Wiethe patient identified only as S.M. Despite their best efforts, including exposing her to scary movies, haunted houses, and venomous snakes, S.M. never got scared. They had her journal her emotions for months, and fear never entered the picture.

In her personal life, SM lives in a dangerous area. She’s been held at knife-point twice, gunpoint twice, and has been the victim of near-fatal domestic violence. Yet, S.M. never felt fearful. However, in 2013, researchers did make her feel fear by having her inhale air with a lot of carbon dioxide in it. This suggests that the body might deal with fear associated with internal and external threats differently. A total lack of fear doesn’t seem to happen in every instance of Urbach-Wiethe, but to be fair, we have a pretty small pool to pull from: Only 400 cases have been reported since 1929.

5. Not being able to feel an emotion is one thing, but not being able to physically feel pain is another—which is exactly what a condition called Congenital Insensitivity to Pain causes. It happens when people’s nociceptors, the things in our nervous system that make us feel pain, don’t work correctly. (Or at all.) It’s an umbrella term for multiple genetic diseases and has been estimated to occur in about 1 out of a million people. And while it kind of sounds like a good thing—who wouldn’t want to skip the pain of a stubbed toe or a paper cut?—CIP is actually extremely dangerous. Imagine not being able to feel that your appendix has burst, or the chest pain that warns you of a heart attack. Even small things, like scrapes or cuts, can become fatal when infected and left untreated. People with CIP have to be constantly vigilant for self-inflicted wounds on their tongue, lips, eyes, ears, nose, and fingers. You know how bad it hurts when you accidentally bite your tongue or cheek—what if pain didn’t stop you from biting down? Some people with CIP also can’t sweat, which means it’s much easier to overheat, get heat exhaustion, or even heat stroke.

6. A lot of things cause hives, which are medically known as urticaria. Allergies, medications, heat, cold, sunlight, even stress. But here’s a cause you probably didn’t have on your bingo card: water. While tons of people experience hives for one reason or another, there are only 100-250 documented cases of aquagenic urticaria in the world. As you might suspect, it makes everyday life pretty difficult. Sweating and crying can trigger a reaction, and showering or bathing can be almost impossible. Many people with aquagenic urticaria cut down on bathing, or choose to use an alcohol-based cleanser instead of water.

One woman suffers so severely from the condition that taking a quick shower causes her scalp to bleed, and even drinking water produces a burning sensation internally. She mostly sticks to milk, but avoiding water has sometimes left her so dehydrated that it has caused other major health concerns. There are treatments for aquagenic urticaria, but they’re all met with varying degrees of success—and they’re treatments, not cures.

First, there are good old antihistamines, which are recommended for many types of allergies. Another option is to use creams or petroleum jelly (a.k.a. Vaseline) to prevent water from touching the skin. And finally, sometimes phototherapy using ultraviolet light can be effective. The right treatment can totally solve the issue for some patients, while nothing seems to work for others.

So what causes it? It’s so rare that it’s still a bit of a mystery. There are a few theories, including that the water is allowing some antigen on the skin to diffuse into the dermis, or that pressure changes are to blame.

That’s it for this episode! Got a topic you want to know more about? Let us know in the comments. I’ll see you next time.