Oct 07, 2020

With the advancement and research in modern medicine, we have many useful drugs these days which aid in the treatment, recovery and management of many disorders and diseases. They help in improving the overall quality of life. 

Medicines can cure and treat many health problems. But have you ever wondered why doctors and medical experts advise us to consume some medications empty stomach and some with meals? It is due to the reason that diet and lifestyle affects the absorption rate of medications to a great extent. At times, the foods we eat can either interfere with the drug metabolism or may enhance the absorption. 

Hence, in this article, we will discuss nutrient drug interaction which means the specific changes caused in the absorption or metabolism of medicine, in the presence of dietary nutrients. The effect may either increase, decrease or result in the production of a new effect. 

Nutrient drug interaction consequence might occur due to the following reasons -

  1. Delayed gastric emptying
  2. Changes in the gastrointestinal pH
  3. Binding of different components of the drug
  4. Competition with nutrients for binding sites


  1. Calcium containing dairy products have shown to decrease the absorption of certain antibiotics like tetracycline, therefore, consuming them together should be avoided.
  2. People who are on antidepressant medicines should avoid excess intake of foods rich in tyramine like cheese, bananas, yoghurt and cured meats. It is because tyramine acts as a vasoconstrictor and augments blood pressure.
  3. People on anticoagulants and blood-thinning medications like warfarin, should avoid consuming them with vitamin K rich foods such as green leafy vegetables, tomatoes, etc. as these can decrease the anticoagulant effect of medicines. Vitamin K is required by our body for blood clotting.
  4. People taking psychotropics should avoid taking them with grapefruit juice as it alters the disposition of the drug. Grapefruit juice has also shown to slow the absorption of thyroxine medicine. 
  5. Liquorice extract is known to increase sodium retention and potassium depletion, and excess is not suitable for people on antihypertensive medications. A person should not take more than one cup of liquorice tea per day.
  6. Medications containing acetaminophen are used to treat fever and mild pain. It should preferably be taken on an empty stomach as food may lessen the absorption.
  7. Alcohol intake should be avoided with bronchodilators as it may increase the risk of side effects like headache, vomiting and nausea.
  8. The bio-availability of anti-tubercular drugs taken for the treatment of tuberculosis is increased when taken with meals except for high-fat meals. 


  1. Prolonged use of antacids has shown to diminish phosphate levels in the body. It can also lead to vitamin D deficiency, increasing the risk of osteoporosis.
  2. Excessive use of diuretics causes loss of electrolytes from the body mainly potassium. It may affect normal heart functioning hence diet should contain potassium-rich foods like banana, coconut water, oranges, tomato, sweet potatoes and raisins.
  3. Women taking contraceptive pills become more prone to develop vitamin D and folate deficiency, hence diet should be rich in foods like amla, guava, kiwi, citrus fruits, green leafy vegetables, broccoli and asparagus.
  4. The risk of vitamin D and folic acid deficiencies are also increased among people on anticonvulsant drugs for seizures.
  5. Some drugs for gout might also alter vitamin B12 absorption, hence diet should be enriched accordingly or opting for a supplement is another alternative. 

Hence, it can be seen that only some nutrients can affect the drug absorption but these drugs can also amend the utilisation of nutrients in the body. At times, it has been observed that people who are on regular medications may complain of anorexia, nausea, vomiting, changes in the gastrointestinal tract, taste changes, dry or soreness in the mouth. However, this interaction may vary from person to person depending upon age, lifestyle and other associated factors. Therefore, one should avoid consuming OTC medications regularly. It is better to consult a physician and take medication if required as per prescribed dosage and timing. 


  • Bushra, R., Aslam, N., & Khan, A. Y. (2011). Food-drug interactions. Oman medical journal26(2), 77–83.
  • Chan L. N. (2013). Drug-nutrient interactions. JPEN. Journal of parenteral and enteral nutrition37(4), 450–459.