Should You Take Supplements?

My colleagues and I at the Penn State Department of Food Science have been involved in developing a low cost calcium-rich confection for the Latin American market. One of the challenges we faced in our product development process was whether to define our product as supplement or food. The Food and Drugs Administration has different guidelines on what can be called a supplement; that was where I got the idea for this piece: What should we all know about taking supplements?

Historically, supplements referred to dietary supplements which added one or more essential nutrients, vitamins, minerals, carbohydrates, fats, proteins, and water to a person’s diet from a source other than food. Vitamin and minerals were and still are the most popular supplements. A number of dietary supplements have beneficial health effects that are substantiated by scientific evidence. For example, researchers agree that during the first weeks of pregnancy, folic acid in higher doses than typically consumed by diet alone has beneficial fetal health effects.  Therefore, to prevent defects in the unborn child such as spina bifida, the U.S. Public Health Service recommends 400 micrograms of supplemental folic acid daily for all women of childbearing age. Some people may not also consume a variety of foods. For such individuals, selected dietary supplements, including vitamins and minerals, can be taken to ensure adequate consumption of required nutrients.  Also, many elderly patients may be fatigued due to low iron levels for which they may also need iron supplements. In addition to iron supplements, routine intake of vitamin D supplements is recommended for older adults among whom vitamin D deficiency is common. Athletes and convalescing patients are also easily prescribed supplements to maintain health.

For this reason, many people find it a healthy habit to buy and use supplements. The supplement market is huge. Over 1,000 new dietary supplements are added annually to the 29,000 already available. But it is important to note that not all supplements are created equal, and some can actually cause more harm than good if used improperly or if you have existing health conditions. Therefore, one should be careful in the selection and use of these products.

Although established pharmaceutical and nutrition companies manufacture some dietary supplements, the industry is largely unregulated and not standardized. Some critics even believe that some manufacturers in the supplement industry take advantage of the unregulated environment and take chances with public health.

The industry is unregulated because dietary supplement manufacturers are not legally required to perform pre-market clinical studies or formal research on the safety and efficacy of dietary supplements. Some manufacturers and consumers mistakenly consider historical use as a proxy measure of the safety and efficacy of dietary supplements, especially for herbal remedies that have been used for hundreds of years. How­ever, reliance on historical use as a measure of safety is problematic for several reasons.

Firstly, herbal treatments vary widely in the concentration of active ingredients from one preparation to another; therefore, assumptions about safety based on one preparation may not apply to another. Secondly, traditional healers may have extensive knowledge about which parts of plants to use in which ways and when and where to harvest them. However, this knowledge may be lost in the transition of a remedy from tra­ditional settings to the modern context. Lastly, genetic differences mean that one group may tolerate a particular substance but it may pose greater risks to another group or to the general population. Risks associated with alcohol, for instance, are varied for different genetic sub-groups of the population.

These reasons are even more serious with respect to children. For starters, because it is not legally required, most dietary supplements have not been tested for safety or efficacy in children.  There are no dosage guidelines for the administration of dietary supplements to children; therefore, appropriate dosage may be difficult to ascertain. The dosage levels of most dietary supplements are generally set for adult usage, with many children’s dosages expressed as fractions of an adult dose. But this is problematic because the absorption, distribu­tion, metabolism and excretion of dietary supplements differ in children and adults. In addition, children may be particularly susceptible to the effects of dosing variations because of their smaller size and different capacity for chemicals.

What you should do:

It is advisable not to take conventional medications concurrently with herbal supplements or high dose vitamins. Interactions between dietary supplements and pharmaceutical drugs can interfere with the absorption, metabolism, or excretion of drugs and this is especially high among the elderly because older people do take more medications than younger people do.

Additionally, in your consideration of supplements do not be swayed by the words you normally see on supplements such as “natural.”  The word “natural” is not synonymous with the word “safe.” In a lot of cases, there is no evidence for the safety of these “natural” supplements and where there is evidence, the lack of evidence of harm does not necessarily indicate that a dietary supplement is safe but rather that there is no evidence to the contrary.

Lastly, if little supplement is good, more is definitely not better. Adverse effects of consuming excessive amounts of dietary supple­ments can cause toxic effects. For example high calcium intake may lead to high blood calcium levels, kidney stone formation and kidney complications.

So should you use supplements?  The advice is to start with a balanced diet and use only the supplements that you need to meet nutritional requirements that are not being provided in your diet. Also, with few exceptions, including folic acid, dietary supplement use is generally not advised during pregnancy because little is known about the placental transmission of most supplements. If you are in doubt, talk to a dietitian, a nutritionist or your doctor.

 

Julius Ashirifie Gogofio is a food research scientist with a Master’s Degree in Food Science from Pennsylvania State University.