When it comes to taking dietary supplements, it is essential to be aware of any special instructions that may be necessary when consuming them with food or other beverages, such as alcohol or drinks containing caffeine. Dietary supplements that contain added caffeine should include this ingredient on the label, but there is no need to indicate the amount. Carbonated soft drinks and other conventional foods and beverages that contain added caffeine should also include this ingredient on the label, but again, there is no need to specify the amount. Foods and beverages that contain natural caffeine do not need to indicate that the food contains caffeine.
If caffeine is listed as part of a “proprietary blend”, the amount of the blend should be indicated, but not the amount of caffeine contained in the blend. Drug interactions are usually the first thing that come to mind when considering food and drug interactions. However, drug-food interactions and drug-herbal interactions can also exist. These may be due to accidental misuse or a lack of knowledge about the active ingredients involved in the relevant substances. Food and drug interactions can inadvertently reduce or increase the effect of the drug.
Some commonly used herbs, fruits and alcohol can cause therapy to fail to the point of seriously altering a person's health. Most clinically relevant food-drug interactions are due to food-induced changes in the bioavailability of the drug. The main side effects of some diets (foods) on drugs include the alteration of absorption by fatty diets rich in protein and fiber. Bioavailability is an important pharmacokinetic parameter that is correlated with the clinical effect of most drugs. To assess the clinical relevance of a food-drug interaction, it is also necessary to quantify the impact of food intake on the clinical effect of the drug. The most important interactions are those associated with a high risk of treatment failure due to significantly reduced bioavailability in the diet state.
These interactions are often caused by chelation with food components. In addition, physiological responses to food intake, such as gastric acid secretion, may reduce or increase the bioavailability of certain drugs. Coenzyme Q-10 (CoQ) is widely consumed by humans as a dietary supplement due to its recognition by the public as an important nutrient in supporting human health. It interferes with glycoprotein P (P-gp), a transporter of intestinal efflux, and as a result interactions between food and medication occur. The interaction of natural products and drugs is a common hidden problem found in clinical practice. Interactions between natural products and drugs are based on the same pharmacokinetic and pharmacodynamic principles as drug interactions.
Recently, several fruits and berries have been shown to contain agents that affect drug-metabolizing enzymes. Grapefruit is perhaps the best-known example, but Seville orange, grapefruit and carambola also contain agents that inhibit cytochrome P450 3A4 (CYP3A), which is one of the most important enzymes in drug metabolism. It is important for users to be aware that certain foods and herbs can interact with medications and cause serious health problems if taken together. Therefore, users are advised to avoid taking certain types of dietary supplements with food or other beverages such as alcohol or drinks containing caffeine without consulting their doctor first.
