I bet you never thought that grapefruit juice could kill you. Did you? No you didn t. Don t lie.
It s so delicious! Look at this girl she clearly LOVES IT. How can something sooooo good be soooooo bad? What we are going to try to convince you all of today is that grapefruit juice is not grapefruit juice it is a DRUG. This girl here is taking drugs. Here s why we say this:
Turns out that grapefruit juice can interact with a lot of other drugs/medication that you are. Grapefruit can interact with over 40 medications that would lead to lethal side effects. Are you thinking what I m thinking?! That s so interesting! How can a juice be a drug? How can it be lethal? Tell me more! Ok, if you insist! It turns out that grapefruit contains furancoumarins, and furancoumarins inhibit the enzyme CYP3A4 which lives primarily in our gut and liver.
When you take medicine (or eat food), the molecules travel through your digestive system and are absorbed through transporters (and/or broken down slightly by enzymes) in the cells lining the small intestine. Grapefruit juice can interfere with both of these processes. Some medicines, such as cholesterol medicines, are metabolized by the CYP3A4 enzymes in the small intestine. Grapefruit blocks the enzyme, increasing the amount of medicine absorbed by the body and risking overdose. Other medicines, such as Allegra, get into the body s cells via transporters. Grapefruit blocks these transporters, decreasing the amount of medicine absorbed which decreases the effect of the medicine
Here s how this enzyme works. Say you are taking a cholesterol medication. As it enters your digestive system it is at 100% strength as it has not really been broken down by intestinal enzymes. However, when it gets to the enterocytes of the small intestine, this drug is metabolized/broken down by the enzyme CYP3A4. As a result, only about 30% of drug is absorbed into the blood stream. This is what is called the bioavailability the drug (the amount of drug that is actually absorbed). Additionally, the drug can also be broken down once inside the body via the same CYP3A4 enzymes found in the liver. This is what happens normally in all of us-drugs are broken down and the dosage we get is lower than what came in. So what would happen in this picture of CYP3A4 was inhibited by grapefruit juice? What do you all think?.. The dosage absorbed would be 100%! This could lead to an overdose on the drug.
Whatever, that s just boring physio stuff. How does grapefruit affect anyone in real life? Grapefruit increases the effect of the certain medicine. Ok, I know what you re thinking:who CARES?! YOU SHOULD CARE!! Grapefruit juice increases the effect of Tegretol in the blood by inhibiting its breakdown via the CYP3A4 enzyme. Tegretol is used to treat epilepsy, bipolar disorder and neuropathy. Grapefruit stops the enzymes from breaking down the Tegretol and so the levels of the medicine remain high in the blood. High Tegretol levels are dangerous and can cause:
For many individuals, these side effects can be diverse and severe including: complete heart block torsade de pointes (rapid heartbeats that can lead to sudden death) rhabdomyolysis (severe damage to skeletal muscle that can lead to kidney damage) nephrotoxicity (kidney damage) myelotoxicity (damage to bone marrow) respiratory depression (reduced or slowed breathing).
So does grapefruit make all drugs dangerous? No! But there are some common characteristics of the drugs that become dangerous: They are all taken orally (which means they have to be broken down by CYP3A4) They are given at higher dosage (which means people are at a greater risk of overdosing if CYP3A4 is not working) Most importantly, they are all metabolised by the enzyme CYP3A4 that is inhibited by grapefruit juice
Is grapefruit juice the only food that does this? No, it is not the only one. Black licorice can interfere with some medicines, but that s ok because it s nasty. Some citrus fruits and vegetables also contain furanocoumarins Vitamins and supplements can also interfere with medications. Please check with your pharmacist before starting a new medication, vitamin or supplement.
Conclusion: stop eating grapefruits and detonate/explode all of them in the world right now!!! Except not really.
Like all things in life, there s always some good with the bad
Turns out that people have noticed that diabetics who drink grapefruit juice often see that their blood sugar levels are significantly reduced. What??!?!?! That s random. Before we explain the power of grapefruit juice in this process, let s first review the basics of what diabetes is:
Diabetes is the state of constantly elevated blood glucose levels. You can see on the picture on the left a blood vessel from a normal person, and on the right a blood vessel from someone with diabetes showing elevated blood glucose levels. So what causes this:
One cause of diabetes is insulin levels that are too low or insulin that is ineffective. As a result, blood glucose is not sufficiently metabolized or broken down and they get too high.
Another cause has to do with the liver. Turns out the liver is not just your friend who will help you detox after a crazy night out. It can also help raise blood glucose levels if you ever need some more glucose. So, the liver is a glucose factory that can also help raise blood sugar and in diabetics cause some problems.
Okay, so what?! What does this have to do with GRAPEFRUIT JUICE?!??!Turns out that researchers found grapefruit juice can help diabetic patients!! We want to quickly review a research study we came across that showed this to be the case:
What the researchers did is they took a few groups of rats. There were many groups of rats in the study, but we are going to just show you two for simplicity. They had one group of diabetic rats who were not given grapefruit juice, and one group that was. That s all they changed between the groups. And thennnnnnn.
Voila! The mice that drank grapefruit juice saw LOWER BLOOD GLUCOSE LEVELS, LESS WEIGHT GAIN. You can see in this figure from the paper that the rats that were treated with grapefruit juice (labeled GFJ) had lower blood glucose than those that weren t (D45 and D60). Also, they had the same blood glucose levels as diabetic rats treated with insulin (Ins-D60 group). WHAT?! SO THEN THE RESEARCHERS tried to figure out why. Why was the group 2 rat s glucose levels so much better. Turns out that it wasn t because they were producing more insulin.
What they found is that grapefruit juice inhibits the liver s ability to produce more glucose. In that way, the diabetic rat produces less glucose which will help lower blood glucose levels. The liver still helps you detox (don t worry), but just can t produce glucose as well which is great for diabetics.
In summary, we hope we convinced you that grapefruit juice is a drug. It can interact with other drugs to alter dosage, and it can even help temporarily reverse the dangers of high blood glucose. So if you eat grapefruit, next time someone asks you if you re on drugs you say, Yes. Yes I am. Any questions?