7 Things You Should Never Ingest

From the time we're toddlers, we start building up a list of things not to put in our mouths. Bananas? Yes. Mom's iPhone power socket? No. But in the adult world, as we start taking medications and becoming in charge of our own nutritional choices rather than fed via airplane spoon, things can be a bit less clear. Should we eat that uncooked egg? (Science says, generally, no, even though the risk of salmonella is very low.) What about that exotic Japanese delicacy, fugu ? (It's puffer fish, and if you're unlucky it can indeed kill you.) And what about medications that seem not to be working yet; it can't be that bad to take a double dose, right? (Yes. Yes it can.)

There are some substances that are actually pretty safe to swallow, despite their reputations. Chewing gum, for instance, does not take seven years to leave the digestive system, like the urban myth says; except in extremely rare cases, it will pass through without doing you any harm. Others, however, should be avoided for their health consequences at all costs, because of the presence of toxins or the possibility of wreaking havoc on your digestive system.

So you may have graduated from needing to be told not to put the dog's food in your mouth, but there are still some rules you may not have realized you need to follow. Here are seven substances never to ingest, under any circumstances.

1. Prescription Medication That Belongs To Somebody Else

This is a surprisingly common mistake and should be avoidable. No, it is not a good idea to "test" a medication on yourself by nabbing the dosage from somebody else. This includes more "casually" traded drugs like Adderall and Valium, but it's also a sensible policy regarding any prescribed medication, from antidepressants to blood pressure meds to insomnia drugs.

On a basic level, you're messing up another person's dosage, even if they're willing to give some to you. You also haven't gone through the medical checks that are necessary to make sure that drug and dosage are safe for you, so please don't put your health at risk by doing this nonsense.

(The ONLY exception to this is if you're on the exact same drug and dosage and one of you faces an emergency shortage before you can renew the prescription. But even then, it's to be avoided.)

2. A "Double Dose" Of Any Drug "To Make It Work Faster"

No, this is not how a lot of medications work. A double dose of painkillers, for instance, is not likely to make things work "faster;" there's a reason why painkillers have a recommended maximum dosage in a day, and if you exceed that you're likely putting yourself at high risk for serious health consequences. (Too much paracetamol, for instance, can cause hemorrhage.) It's also a good rule of thumb for meds in general, whether they're prescribed or over-the-counter; if you feel the dosage hasn't done anything, generally speaking you still have to wait the recommended time before you can take another dose or try something else. If you have questions, call your doctor or your local poison hotline.

3. Two Medications For Different Symptoms With The Same Active Ingredient

This is how something called a "medication error" happens in the medical community: if somebody doesn't tell their doctor what medications they're on, and is prescribed something else with the same active ingredient, they may be setting themselves up for an overdose. For instance, the Mayo Clinic outlines the serious risks of taking Wellbutrin and Zyban at the same time, or any two pain medications containing acetaminophen.

This isn't the case for all medications that share active ingredients, but to prevent miscommunications and possible nasties for yourself, always make sure every doctor and medical professional treating you knows everything you're on. (Don't assume anything. Take a list. Doctors can fail to talk to one another, too.)

4. Any Wild Mushroom Or Berry You Can't Exactly Identify

This sounds wildly Agatha Christie, but getting your kicks from foraging has its dangerous side. If you think a mushroom from a garden or wild place looks benign but don't have an expert or a trusted source on hand to make sure it's not poisonous, please leave it where it is. Same with berries: they may look tasty, but the berries of the yew tree, for instance, are incredibly poisonous. If you don't know what it is and nobody tells you it's safe, just take a photo and leave it out of your salad, OK?

5. Potatoes That Have Been Left To Turn Green

Potatoes that have been left alone do several things: they sprout from their eyes, and they also start to turn a brilliant green color. While very pretty, this is a sign that they're definitely unsafe to eat and need to be thrown out immediately. It sounds like an urban myth, but the green color indicates that they've become poisonous, though it's not the green color itself that's causing the problem.

The green is caused by chlorophyll, in itself harmless to humans; but that chlorophyll development is accompanied by high levels of the toxin solanine, which is exclusive to the nightshade family of plants. (Yes, deadly nightshade is related to the humble potato, and solanine is unfortunately their family bond.) Solanine poisoning isn't something to take lightly, either. It's been known to cause severe gastrointestinal problems, hallucinations, comas, and even death. Yes, even when they've been cooked. Get the green tubers out of the kitchen immediately.

6. Dietary Supplements You Haven't Researched

Here's the thing to remember about dietary supplements of any kind: they're not under the same FDA regulations as foods and medications, and don't have the same legal restrictions on their labelling and ingredients. This is particularly important because scientists testing dietary supplements and finding stuff that definitely should not be in them.

A 2015 Harvard study investigated dietary supplements containing the herbal stimulant Acacia rigidula , and they found, shockingly, that they tended to contain an untested amphetamine called BMPEA, which has very few studies about whether it's actually safe for human consumption. No sign on the label of that particular ingredient. Many of the tested supplements were produced by the same company, Hi-Tech Pharmaceuticals, but they're under no legal obligation to change anything. If you're contemplating buying anything from the supplements aisle, check its labels and then do thorough research on whether it contains what it says it does. (In some cases, alas, you may never know.)

7. Raw Red Kidney Beans, Cassava, Or Rhubarb Leaves

We all know that raw chicken is an incredibly poor idea to ingest, but there are other substances that, taken raw, will actually cause serious gastrointestinal distress and rapidly ruin your weekend plans. Among them are cassava and the leaves of rhubarb; we normally only eat the rhubarb's pink-red stems, and there's an exceptionally good reason for that. The leaves contain oxalic acid, which can cause seizures, breathing difficulties, vomiting, and comas. This was apparently a particular problem when it was recommended as a food source during rationing in Britain in World War I. Whoops.

More surprisingly because of how commonly people eat both, reheated cooked rice or pasta is also a very poor plan because of its high moisture content, as are red kidney beans in their raw form. Uncooked, the beans contain the toxin phytohaemagglutnin, which is drastically reduced by cooking but exists so strongly in the raw bean that a mere four or five of them can bring on serious vomiting and gastrointestinal problems. Nope nope nope.

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