Nutritional supplements are preparations intended to supplement the diet and provide nutrients (Aina and Ojedokun, 2014). They include vitamins, minerals, fiber, fatty acids, or amino acids, which may be missing or may not be consumed in sufficient quantities in a person’s diet (Aina and Ojedokun, 2014). Caballero (2006) also defines dietary supplements as: “products (other than tobacco) intended to supplement the diet that bears or contains one or more of the following dietary ingredients: vitamins, minerals, amino acids, herbs or other botanical”. The definition by the National Institute of Health’s Office of Dietary Supplements gives a definition which also agrees with the two previously given: it defines dietary supplements as “products intended to supplement the diet and which contain one or more dietary ingredients (including vitamins, minerals, herbs or other botanicals, amino acids and other substances) or their constituents” (Gardiner et al., 2007).

Herbal supplements are one of the notable types of dietary supplements, from the definitions given above (Caballero, 2006; Gardiner et al., 2007; Aina and Ojedokun, 2014). In 2005, the World Health Organization (WHO), defined herbal supplements as plant-derived materials or preparations with therapeutic health benefits, which contain either raw or processed ingredients from one or more plants (WHO, 2005). Also, according to Staines (2011), herbal supplements may also be called herbal medicines, remedies, supplements, botanicals, or phytomedicines.

Individuals of practically all age groups make use of these supplements for a variety of reasons such as, for weight loss, fertility, combating colds, to delay ageing, enhancing brain function, body building, etc (National Health Service, UK, 2011). A recent research at the University of Lagos, Nigeria, involving students of the College of Medicine (Aina and Ojedokun, 2014), found that about 86% of the subjects surveyed had made use of dietary supplements. Also, a community-based survey in a rural population in the United States, involving 526 subjects (211 male and 314 female, with ages ranging from 18 to above 65 years, and including health workers, students, retired adults, unemployed, etc.), found that 71.5% of the subjects preferred dietary supplements or herbal products to prescription medication and over-the-counter (OTC) medicines for treating medical conditions and/or to maintain health (Owens et al., 2014). With these in mind, questions easily arise regarding how much knowledge people actually have about these supplements, in terms of how they should be used, appropriate quantities that should be taken, awareness of their safety, etc.  However, according to Aina and Ojedokun (2014), “there is limited number of research on dietary supplement use in developing countries like Nigeria.” This may imply poor awareness and/or an insignificant use of dietary supplement in our country, thus necessitating the question as to awareness and use of dietary supplements among the Nigerian populace.

Recent years have seen a massive boom in supplement use, as products that were once the preserve of specialist health food stores have become available alongside provisions and foodstuffs in the supermarket and on the internet (National Health Service, UK, 2011). As availability has grown, so have sales. In 2009, the UK market for dietary supplements and vitamins was worth more than £670 million (National Health Service, UK, 2011).

This study is focused on undergraduates – youths, and perhaps it would be useful to take a brief look at the youths of Nigeria. The National Youth Development Policy (2001) defined youth as people aged 18-35 years. It is a stage in life when a person is young, especially the time before a person becomes an adult (Hornby, 2001). Omede (2012) opined that: “psychologically, it refers to the stretch of time in-between childhood and adulthood, and characteristically, youths at this stage of growth and development are biologically known to be full of libidinal energy and ideas, and are also numerically known to outnumber the middle-aged and the aged (Omede, 2012). The Nigerian youths, according to Anasi (2010), constituted about 40% of the more than 140 million people in the country (Anasi, 2010).

A vast population of these youths are concentrated in institutions of higher learning, thus making these institutions a vital venue for researches concerning youths. Higher institutions are obviously the last center of massive convergence of youths before they are released into the outside world. Hence, it would be useful and fundamental to carry out such a research as this concerning dietary supplements (which are increasingly becoming a matter of concern worldwide), among undergraduates, so that corrective actions can be taken against any erroneous or deleterious attitudes, misinformation or misuse of these supplements, which they may have acquired or be involved in.


Dietary supplements are used by so many, in one form or the other. Some even use or have used several different supplements at a time (Aina and Ojedokun, 2012). Researches indicate a rise in their usage worldwide (Strachan, 2009; Elder and Nisly, 2011). Unfortunately, a lot of these users are largely ignorant of appropriate usage of the supplements. For instance, in the research conducted by Aina and Ojedokun, (2014), “almost two-thirds of the students said dietary supplements can be used to substitute natural nutrients derived from foods, which indicates some knowledge deficiency, because dietary supplements are supposed to supplement and not substitute natural nutrients from food” (Aina and Ojedokun, 2014). Also, several of these supplements contain substances which may elicit dangerous side effects or have adverse reactions with drugs or other foods which may be ingested with them (Owens et al., 2014). Hence, it is increasingly becoming important to find out how much users of these dietary supplements know about them (including their side effects or any dangers associated with their usage), how often they make use of them, and the diverse attitudes individuals have towards these supplements.


General objective

The general objective of this research is to assess the knowledge, perception and use of dietary supplements among undergraduates.

Specific objectives:

The specific objectives are to:

  1. assess the level of knowledge of undergraduates about dietary supplements.
  2. ascertain their perception towards the use of dietary supplements.
  3. determine the use of dietary supplements.
  4. assess the relationship between dietary supplement use, knowledge and perception.


This study will add to the body of knowledge on dietary supplements in Nigeria, thereby increasing awareness about these supplements, including their appropriate use, harmful ingredients contained in some, side effects, etc. Results from this research could help nutrition and health professionals to better understand the situation of Nigeria, in terms of dietary supplements, particularly in the aspects of the knowledge of the youths about dietary supplements, including appropriate use, side effects, and their various attitudes towards these supplements.

Besides these, results from this study could stimulate individuals and corporate bodies towards creating more awareness and providing reliable knowledge to the youths and the entire nation vis-à-vis dietary supplements, so as to attempt to positively influence them in order to encourage appropriate use, thereby preventing detrimental side-effects