‘Taking medication? These healthy foods can mess with your meds’

Nov 02, 2020
Grapefruit juice is a big no-no when it comes to the majority of medications. Source: Getty.

There’s no doubt many of the pharmaceutical treatments that are administered to people may have significant interactions with other aspects of our life. One very well recognised scenario is the interaction between a variety of foods and commonly prescribed pharmaceutical drugs. Certain foods may affect how well a drug is absorbed either increasing or reducing absorption.

Leafy green vegetables

Warfarin has been around for many years and is commonly used by people with an artificial heart valve, atrial fibrillation and clotting in veins known as deep vein thrombosis (DVT) or pulmonary embolism.

When you’re on warfarin you have to be very careful with what you eat, what you drink and what other medications and supplements you take. Certain medications like painkillers, a number of antibiotics and specific foods like leafy green vegetables can affect how well warfarin works. For example, leafy green vegetables are loaded with vitamin K which competes directly with the action of warfarin.

Calcium-rich foods

Commonly prescribed antibiotics such as tetracycline and ciprofloxacin shouldn’t be taken with milk and other calcium-rich products. The calcium may bind to the drug in the gut and therefore reduce absorption.

Pickled, cured and fermented foods

Pickled, cured and fermented foods shouldn’t be mixed with some old-style antidepressants known as monoamine oxidase inhibitors (MAOIs), which are not commonly prescribed these days. These foods, especially cheese, are loaded with an amino acid called tyramine which can markedly increase the activity of these drugs. Some drugs prescribed for Parkinson’s disease can also be affected by these types of foods so it’s very important to speak with your doctor about what foods you can eat if you are prescribed any of these drugs.

Grapefruit juice

I believe we should be avoiding grapefruit juice if we are on any type of medication, in particular statin drugs, some blood pressure medications and some drugs used for treating mental health disorders. Why? Grapefruit juice may interfere with absorption.


There are two commonly prescribed blood pressure drugs known as angiotensin-converting enzyme (ACE) inhibitors and Angiotensin II receptor blockers (ARBs) which shouldn’t be taken with potassium-rich foods like bananas. Bananas have a relatively high concentration of potassium and these two blood pressure drugs may elevate your potassium somewhat. If you enjoy bananas, and your blood pressure is high, it’s important to have your potassium levels measured (which, in my opinion, should be done regardless because you have high blood pressure) along with your kidney function. If your potassium is above the normal range you should reduce your intake of potassium-rich foods such as bananas and tomatoes. However, it’s important to note, this is not a particularly significant issue for most people.

In most cases, I’d recommend taking your medication at least one hour before or two hours after eating. If you are on any of the medications I have mentioned, ask your doctor or pharmacist to give you a full list of the foods you can enjoy and the foods you should avoid. This straightforward conversation may be the difference between the prescribed medications working, having no effect, or potentially having some very serious side-effects.

IMPORTANT LEGAL INFO This article is of a general nature and FYI only, because it doesn’t take into account your personal health requirements or existing medical conditions. That means it’s not personalised health advice and shouldn’t be relied upon as if it is. Before making a health-related decision, you should work out if the info is appropriate for your situation and get professional medical advice.

Become a Starts at 60 Member now.

Starts at 60 Members get a whole lot more value here. It’s free to join and you’ll get:

  • Exclusive emailers with the latest news and leading insights from retirement experts
  • Free online Retirement Masterclasses and other events
  • Amazing deals on tours, cruises, and community holidays from Travel at 60
  • And *new* an ecommerce marketplace just for over 60s with exclusive member offers

What are you waiting for?

Join for freearrow_forward

What are your thoughts on this story? Did you know this?

Please sign in to post a comment.
Retrieving conversation…
Stories that matter
Emails delivered daily
Sign up