Column: Interactions among nutrients, drugs and medicinal herbs are complex

It’s common to turn to nutritional supplements, drugs and herbs to try to boost health. All of these options can be beneficial when used appropriately, but they all come with potential risks as well. Misusing or neglecting to check interactions between nutrients, drugs and herbs can cause irreversible health issues — even death.

Question: How are nutrients, drugs and herbs different? How are they similar?

Answer: Essential nutrients are chemicals needed to survive, grow and reproduce. That means a deficiency of essential nutrients will cause health problems, although the damage of a deficiency (like osteoporosis or B12 deficiency) can take decades to show up.

Drugs are a diverse category of chemicals used in measured dosages. They are primarily designed to treat specific physical or mental symptoms or to slow and control disease progression. Initially, drug chemicals were extracted from medicinal plants, but today most drugs are synthesized under laboratory conditions and standardized to assure specific amounts.

Botanically, herbs refer to plants that do not produce a woody stem. Medicinal herbs can contain both essential nutrients and drugs that can affect how the body functions. However, the amounts of active components in an herb can vary significantly from one source to another due to variable soils, growing conditions and processing techniques used to produce herbal products.

Q: What are the potential risks associated with the use of nutritional supplements, herbs and drugs?

A: Individually and in the proper dosage, all three can be safe and potentially beneficial. However, high dosages and combinations of some of these products can have the potential to cause serious health problems. Adverse interactions are extensive and widely underappreciated.

Some nutrients can interfere with the absorption of other nutrients. For example, consuming a calcium-rich food or supplement combined with an iron-rich food or supplement significantly reduces iron absorption. Regularly using various drugs increases the body’s need for numerous essential nutrients.

Many natural herbs can increase or decrease the effect of some medicines, which could lead to adverse, unexpected side effects. Because the quantities of active chemicals may not be standardized in herbal products or screened for toxic heavy metals, there could be unforeseen consequences.

In the hierarchy of the body’s needs, consuming adequate essential nutrients ranks first and promotes health. It’s relatively easy to determine what’s safe in addressing nutritional needs when a person is healthy and not consuming drugs or medicinal herbs. Once these are added to the equation, determining nutritional needs gets complicated fast. While drug interactions can be checked online at reputable websites, it is more difficult to identify how both drugs and medicinal herbs affect nutrients.

Alan Titchenal, Ph.D., C.N.S., and Joannie Dobbs, Ph.D., C.N.S., are nutritionists in the Department of Human Nutrition, Food and Animal Sciences, College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa. Dobbs also works with University Health Services.