Nutrition Knowledge: Application and Perception of Food Labels Among Women
Knowing the level of consumers nutritional knowledge
is useful for promoting dietary habits. The aim of this study was to assess
womens nutritional knowledge and their food label perception and their
correlates. Three hundred and eighty Women referring to four large supermarkets
in Shiraz were selected for this study. Data were collected through face-to-face
interview. The NKQ questionnaire was used for designing the study questionnaire.
The first part contained demographic characteristics and the second section
encompassed questions related to nutritional knowledge of consumers about food
components. The third part consisted of questions about labeling. Data were
analyzed using SPSS 16. ANOVA and t-test were used for analyzing multi-variant
variables. Chi-square test was used for evaluating the relationship between
variables. 49.7% of the participants were healthy and others had chronic diseases.
The mean score of the womens nutrition knowledge was 20.13 (from 24) and
the average knowledge of women about food components were near 50%. Consumers
information about food labels application was less than 50% for all situations.
The lowest use of labels was about low-salt labels and the highest for calorie
content of foods. There was a significant relationship between educational status
and food label use and also a significant relationship between information about
added sugar and using low-sugar labels and between knowledge about low-salt
foods and using low-salt labels. A significant relationship was also seen between
knowledge about fat and cholesterol use for low fat foods. So, label application
was correlated with educational level and nutritional knowledge of women.
Received: March 14, 2013;
Accepted: May 16, 2013;
Published: September 16, 2013
Nutritional knowledge of consumers and their perception about food labels are
very important tools for improving dietary patterns toward a healthy diet (De
Vriendt et al., 2009; OBrien and Davies,
2007). Health problems due to nutrition and dietary habits, including obesity
and overweight, exert a high burden on the society which leads to health epidemic
problems in the 21st century (Fisberg et al., 2004).
Many studies deciphered that nutritional information has a fundamental role
in achieving a healthy life-style in people (Wills et
al., 2009). One of the best ways for delivering health messages on nutrition
and diet to consumers for better food choices is food labeling (Tudoran
et al., 2009). Knowledge on the nutritional labeling can affect peoples
eating habits (Driskell et al., 2008). The ability
for reading, perception and correct application of food labels is very crucial
(Hong et al., 2011). Nutritional labels are
good tools for keeping consumers informed about their food and diet composition
(Graham and Jeffery, 2011). One way for helping consumers
to make healthy food choices is a good policy for labeling (Wansink
and Sobal, 2007). Using nutritional facts on labels can help to reduce daily
intakes of calorie, fat, saturated fatty acids, cholesterol and sodium (Kim
et al., 2000).
In addition, developers of food labels should consider less technical labels
for consumers perception (Lubman et al., 2012).
Today, food labels are important tools providing good information about nutritional
values of products such as calorie content, fat amount and type and etc. (Wills
et al., 2009; Visschers and Siegrist, 2009).
Specific nutritional educations that are common in primary schools in some countries
(Ruzita et al., 2007) can affect nutritional
knowledge of adults and next generations in future.
Knowing the level of consumers nutritional knowledge is very useful for
promoting their dietary habits according to influential variables such as cultural
factors and understanding of food labeling (Carrillo et
al., 2012). However, current data about how food labels are used by
consumers in shopping situations are rare (Bonsmann et
al., 2010). On the other hand, specific information of different populations
about their nutritional knowledge can be beneficial to link these data to better
food choices and dietary habits, which can be influenced by cultural values
as well (Rozin, 1996).
So the aim of this study was to assess womens nutritional knowledge and their food label perception and to identify their correlates in order to improve their food choices in future through educational programs. This way we can avoid aggravation of their dietary habits and life-style.
MATERIALS AND METHODS
This was a cross-sectional study with 380 participants. Women from those referring
to four large supermarkets (Refah, Sourush,Hyperstar and Etka) in Shiraz, one
of the cities of Iran in Fars Province, were selected for participating in this
study. Participants were recruited through convenient sampling which means recruiting
available participants with the proposed criteria. Data were collected through
face-to-face interview with women referring to the supermarkets for food purchasing.
The NKQ questionnaire (Nutrition Knowledge Question) by Parmenter and Wardle
was used for designing the study questionnaire. NKQ questionnaire is considered
an efficient tool for assessing consumers nutrition knowledge and behavior.
Validity of the questionnaire was assessed through a pilot study in 30 women.
The questionnaire contained 3 parts with the foods consumed commonly in Iranian
population. The first part contained demographic characteristics and disease
history in the participants. While the second section encompassed questions
related to nutritional knowledge of consumers about specific food components
such as fat, sugar, salt and some food groups such as dairy products. This part
included 8 questions that contained 24 options which consumers had to tick one
(Table 1). The answers range from no knowledge to high knowledge
for all of the questions. And finally, the third part of the questionnaire consisted
of 7 questions about labeling which were all specific for this study and predominantly
focused on calorie, sugar, salt and consumers knowledge about labels.
Answers ranged from never to always (Table 2).
Statistical analysis: The data were analyzed using SPSS version 16 (SPSS
Inc.,Chicago,IL). Data were expressed as Mean±SD and frequencies.
||Questions in the second part of the questionnaire, nutrition
knowledge of consumers
||Questions in the third part of the questionnaire, information
about nutritional labels
ANOVA and T-test were used for analyzing multi-variant variables and chi-square
test was used for evaluating the relationship between variables. p-values less
than 0.05 were considered statistically significant.
The 380 women participated in this study. Data were gathered in 2012 over 3 months. After face-to-face interviews, according to the data from the first part of the questionnaire 49.7% of the participants were healthy and the rest of them had chronic diseases, especially high blood pressure. on the basis of the data from the second part of the questionnaire, the mean score of the womens nutrition knowledge was 20.13 (from 24) and the average knowledge of women about fat type and amount, added sugar, saturated fat, calorie content, unsaturated fat, added salt and cholesterol were near 50% (Table 3). With respect to the data from the third part of the questionnaire, consumers information about food labels, effect of labels on purchase intention, specificity of labels, effect of calorie content on purchasing, average of label use for low-sugar, low-fat and low-salt foods are less than 50% for all of the situations (data shown in Table 4). The lowest use of labels for women is related to labels for low-salt foods and the highest for calorie content of foods (Table 4). About the relationship between women educational status and their nutrition knowledge, there was a significant positive relationship between their educational status and food label use (p-value = 0.05).
On the other hand, there was a significant relationship between women information
about added sugar and using low-sugar labels (p-value = 0.05), while there was
a significant relationship between women knowledge about low-salt foods and
using labels related to low-salt foods (p-value = 0.05).
|| Frequencies and percentages of womens nutrition knowledge
about foods and their components
|| Frequencies and percentages of womens nutrition knowledge
about food labels
|| Frequencies of labeling perception responses by nutritional
knowledge about choosing foods
|NS: Non-significant, p-values less than 0.05 are considered
In addition, a significant relationship was also seen between participants
knowledge about fat amount and type and cholesterol use for low fat foods (Table
In the present study, 32.9% of the women always used nutritional labels and
10.5% never used them and this might help consumers eating healthfully by better
food choices (Graham and Jeffery, 2012), while according
to the results of Zhanghualiu study in 2010, 58.36% of men and 80.3% of women
rarely used food labels (Hong et al., 2011)
which shows urgent need for improving nutritional labeling application among
consumers. However in another study by Satia et al.
(2005), 78% of the consumers read the labels at the time of purchasing.
Education presented statistically significant differences in their knowledge
about label use in that study (Satia et al., 2005).
Additionally, in another study by Carillo, a positive relationship between educational
level of consumers and food label use was also seen (Carrillo
et al., 2012) which were all in accordance with the result shown
in the present study.
On the other hand, in a study in 2012, among immigrants in Soviet Union, 55%
of the consumers always or often used food labels and 33% of them had the skill
for reading and understanding the labels (Lubman et
al., 2012). In addition in Carillos study, nutritional labeling
rarely affected food purchases because of consumers problem about understanding
the technical labels (Carrillo et al., 2012),
while in the present study, It is noteworthy that only 6.6% of women mentioned
that the labels' information are too technical and this may be due to the high
educational status of the participants (49.47% of the participants had university
In the present study, it goes without saying that consumers nutrition
knowledge about salt, sugar and fat was significantly correlated with food label
uses. While the highest use of nutritional labeling in the participants was
for low calorie and low fat foods, respectively and the lowest was for low-sugar
foods. In a study in 2010 on UK population, consumers paid attention to the
experts recommendations about calorie intake (Grunert
et al., 2010). However in Cariloos study, consumers mentioned
that they never or rarely paid attention to the food labels for checking low
fat foods (Carrillo et al., 2012). On the other
side of the coin, the highest nutritional knowledge was about added salt and
the lowest about saturated fat. Although in Nayga s study a weak link
between knowledge and purchase behavior was seen (Nayga,
2000). However, Lumbman concluded that there was a good relationship between
food labels perception through avoiding foods high in salt and saturated fat
(Lubman et al., 2012) and Carillo found the
same results according to the effects of consumers knowledge on purchase
decision (Carrillo et al., 2012) which are all
in line with the results of the current study. On the other hand, the results
of Grime 's study were not the same. In his study, more than half of the participants
were unable to use sodium labels. That was partially due to low knowledge of
the consumers and lack of awareness and concern about salt risks (Grimes
et al., 2009). Hence, more education plus friendly labeling formats
are essential for such a population.
Although, this study sheds light on the effects of nutrition knowledge on label
application, there are some limitations as well. The main limitation of our
study is about gender specification for the participants that excluded the males
and this can affect the results as in some studies it was mentioned that women
have better nutritional knowledge than men (Gracia et
al., 2007; Misra, 2007).
To sum up, label use was almost correlated with educational level and nutritional knowledge of women and its crystal clear that consumers nutritional knowledge can affect food labels application. Although most of the consumers were able to understand the food labels, the perception was not easy for less educated women. At the time that governments try to expand efforts for food labeling regulation, the most important point is being sure about the labels application by the consumers in-order to have better food choices. However, governments should design labels with better formats that are understandable and accessible for everyone to reinforce labeling policies. This way, we can avoid neglecting or misinterpreting of labels. So, opinions are divided as to whether nutritional education programs can improve food label application and finally leading to better food choices and it's highly believed that food labeling is a very important form of education to all consumers. This can be a hot topic and a place of debate for future studies.
So, its concluded that nutrition knowledge can affect label perception and nutrition-based educational programs can easily improve consumers knowledge about label application.
This study was done by a grant from Shiraz University of Medical Sciences Shiraz, Iran.
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