Jan 19, 2025 12:00:00

Grapefruit isn't the only healthy food you should be careful about when taking with medicines: 5 foods

Most medications come with warnings to avoid

mixing them with alcohol, but alcohol isn't the only thing you need to be careful of when it comes to interactions with medications. Here are five popular, healthy foods and drinks that experts recommend you avoid mixing with prescription medications.

Five healthy diet staples that may interact with prescription drugs
https://theconversation.com/five-healthy-diet-staples-that-may-interact-with-prescription-drugs-246357

◆1: Grapefruit juice
According to Dipa Kamdar, a Royal Pharmaceutical Association registered pharmacist and lecturer in pharmacy at Kingston University in the UK, the enzyme cytochrome P450 , which is found in the liver, is required for the body to break down drugs.

However, some citrus fruits, including grapefruit and summer mandarins, contain compounds called furanocoumarins, which, when ingested, inhibit the activity of cytochrome P450, resulting in the accumulation of drugs in the body that would otherwise be metabolized.

One drug to watch out for is

cyclosporine , which is commonly used to prevent organ transplant rejection and to control symptoms of rheumatoid arthritis and skin diseases such as psoriasis. If cyclosporine accumulates in the body, it can pose a risk of side effects ranging from mild nausea and vomiting to kidney and liver damage.

There are many medications that may interact with grapefruit, including statins , which are often used to treat high cholesterol and prevent heart attacks and strokes, the high blood pressure medication amlodipine , and the erectile dysfunction medication sildenafil .

'If you're taking any of these prescription medications, talk to your doctor or pharmacist before drinking even a small amount of grapefruit juice, or you may want to avoid it completely,' Kamdar said.

◆2: Pomegranate juice and cranberry juice
Pomegranate juice inhibits a liver enzyme that breaks down the anticoagulant warfarin , which is used to prevent blood clots from forming in people with irregular heartbeats.

Several studies have suggested that drinking pomegranate juice may increase

the international normalized ratio (INR) , the time it takes for blood to clot, in patients taking warfarin, meaning taking pomegranate juice and warfarin together could increase the risk of bleeding.

Additionally, it has been pointed out that pomegranate juice may interact with tacrolimus, an anti-rejection drug used in organ transplants, and it also contains the aforementioned furanocoumarins.

Similarly, cranberry juice is said to affect warfarin, and there have been reports of patients who drank cranberry juice two weeks prior to taking warfarin and then died from bleeding. However, the results of studies on cranberries and warfarin have been mixed, with some finding an effect and others showing no effect.

'If you consume these juices, you may want to check your INR more frequently or keep in mind that fluctuations in your INR may be due to the fruit juice,' Kamdar said.

◆3: Green leafy vegetables
Green leafy vegetables such as spinach, broccoli, and kale are low-calorie, nutritious foods that are rich in vitamin K, which is necessary for activating blood clotting factors.

However, being high in vitamin K can be a problem for people taking warfarin, because warfarin works by blocking vitamin K to prevent blood clots from forming. Even if you take warfarin to prevent blood clots from forming, consuming foods rich in vitamin K can lower your INR, increasing your risk of developing a blood clot.

While green leafy vegetables are an excellent addition to a healthy diet, Kamdar said people taking warfarin should always pay close attention to their INR and consult with their doctor before eating foods rich in vitamin K.

◆4: Milk
Milk is a drink rich in protein and calcium, but calcium binds with some antibiotics in the intestines, so if you consume them together, they will not be absorbed properly and will not be effective.

Antibiotics to watch out for include tetracycline and ciprofloxacin .

In addition to antibiotics, dairy products can also affect levothyroxine , which is used to treat hypothyroidism.

Because the interactions between dairy and medications occur in the gut, it's okay to consume dairy while taking these medications, as long as you time it right. In most cases, Kamdar says, you can eat dairy products two hours before or after taking your medication.

◆5: Beans
Beans are plant-based foods that are rich in dietary fiber, vitamins, minerals, and protein, but soybeans, fava beans, and snow peas may contain high amounts of a substance called

tyramine .

Tyramine is a naturally occurring substance found in legumes, as well as aged cheeses, raw meats and fermented foods, and it may interact with the antidepressant phenelzine .

Phenelzine is a drug that is not used very often these days and is classified as a monoamine oxidase inhibitor (MAOI) .

Phenelzine inhibits the enzyme that breaks down tyramine in the body, so if a person taking phenelzine eats foods that are high in tyramine, the tyramine levels may become too high, causing an increase in blood pressure.

In addition to phenelzine, other MAOI antidepressants include isocarboxazid and tranylcypromine .

'Healthy foods can improve your overall health in many ways, but be sure to check with your doctor or pharmacist before making any major changes to your diet, especially if you're taking prescription medications,' Kamdar concludes.