Return to search

Avocados: consumer beliefs and effect on weight loss and markers of cardiovascular health / Z. White

Motivation
The objective of the South African Avocado Growers Association (SAAGA) is to increase the
demand of avocados by advertising, promoting and other means deemed fit by them. In order to
promote and advertise a product, consumer research has to be done to determine the consumers' attitudes towards and beliefs concerning the product. These findings then need to be followed up by scientific studies, targeted at specific problems and target groups to yield scientific evidence.
Little consumer research has been done on avocados and studies investigating the health effects
of avocados are limited, with available literature only focussing on the cholesterol lowering effect of
avocados.

Objectives
Firstly, the objective is to investigate the beliefs and attitudes of the South African consumer
towards avocados and health; to determine whether gender, age group, race or living standard
influence the consumers beliefs towards avocados.
Secondly, the objective is to dispel the myth that avocados are fattening and should therefore be
avoided in energy restricted diets; to examine the effects of avocados, a rich source of monounsaturated
fatty acids, as part of an energy restricted diet on weight loss, serum lipids, fibrinogen
and vascular function in overweight and obese subjects.

Methods
Consumer study: One thousand nine hundred and ninety-seven South African individuals,
randomly selected from metropolitan areas in South Africa, participated in this survey. Data
were weighed to reflect the adult metropolitan population based on gender, age and race
distribution. The total population (10 695 000) was representative of both genders (5 423 000
men and 5 272 000 women) and major race groups (2 615 000 whites, 6 252 000 blacks,
1 255 000 coloureds and 573 000 Indians) from different age groups and living standards. The
questionnaires were designed by a multidisciplinary team and consisted of seventeen foodrelated
questionnaires, of which one questioned the beliefs regarding avocados. Trained field
workers administrated questionnaires by conducting face-to-face interviews with consumers.
The market research company, MARKINOR, was contracted to collect the data. Quantitative
data was statistically analysed in order to generate the relevant descriptive statistics, cross
tabulations and statistical tests.

SUMMARY
Dietary intervention study: Sixty one free-living volunteers (13 men; 48 women), with a mean
(standard deviation) body mass index (BMI) of 32 (3.9) kg/m2, participated in this randomised,
controlled parallel study. The subjects were paired according to gender, BMI and age and
randomly assigned to one of two groups. The experimental group consumed 200 g of avocado
(1 avocado) per day, substituting 30 g of other mixed dietary fats, and the control group
excluded avocado from their energy restricted diet for six weeks. Seven-day isoenergetic
menu plans were given according to mean energy requirements of both genders to provide
30% fat, 55% carbohydrates and 15% protein of total energy intake. Anthropometric
measurements, physical activity, dietary intakes, blood pressure and arterial compliance were
measured with standard methods at the beginning and end of the intervention. Fasting blood
samples were drawn at the beginning and end of the intervention period.

Results
Consumer study: There were no practical significant differences in the consumers responses
in terms of gender or age. Practical significant differences were found between different race
and LSM (Living Standard Measure) groups for some variables. The overall response of
consumers towards the effect of avocados on health, heart health, children's health and the
health effects associated with the fat content of avocados were very positive. However, almost
half the consumers are still not convinced of or are uncertain as to the cholesterol content of
avocados, while 47% of the consumers still believe that avocados are fattening. More than
80% of the consumers agreed that avocados are a good source of vitamins and minerals, and
76% consider avocados to be a good source of fibre. Almost 70% of the consumers agreed
that avocados are good for sportsmen and -women. Avocados were seen by 49% of the
consumers to be an aphrodisiac.
Dietary intervention study: Fifty-five subjects completed the study. Compliance with avocado
intake in the experimental group was 94.6%. Anthropometric measurements (weight, body
mass index and percentage body fat) decreased significantly in both groups during the study
(p<0.001), and the change was similar in both groups. Serum lipid levels (total cholesterol,
low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides),
fibrinogen, blood pressure and arterial compliance did not change significantly within or
between the two groups.

SUMMARY
Conclusions
Consumer study: There are still a few myths and misconceptions that exist among some
consumers regarding avocados, especially with regard to sexual functioning, cholesterol
content, and fattening effect of avocados. The agricultural industry can use these results to
plan different marketing campaigns focused on certain target groups to change the
misperceptions concerning avocados and convey the positive nutritional value of avocados.
Dietary intervention study: The consumption of 200 g avocado per day, within an energy
restricted diet, does not compromise weight loss when substituted for 30 g of mixed dietary fat.
The serum lipid levels, plasma fibrinogen, arterial compliance, as well as systolic and diastolic blood pressure were not affected by weight loss or avocado intake. / Thesis (M.Sc. (Nutrition))--North-West University, Potchefstroom Campus, 2004.

Identiferoai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:nwu/oai:dspace.nwu.ac.za:10394/127
Date January 2003
CreatorsWhite, Zelda
PublisherNorth-West University
Source SetsSouth African National ETD Portal
Detected LanguageEnglish
TypeThesis

Page generated in 0.0027 seconds