Effect of a Novel Food Portion Control Program (Lifesize®) on Dietary Intake and Body Weight

9/19/2011
Colorado State University
1
Effect of a Novel Food Portion Control Program (Lifesize®) on Dietary
Intake and Body Weight
Final Report submitted to Lifesize, Inc.
September 19, 2011
Principal Investigator: Chris Melby, Professor and Department Head
Department of Food Science and Human Nutrition
Colorado State University
Fort Collins, CO 80523
Co_Investigators: Sarah Fawcett, Cassi Freed, and Darlene Weber_Dewitt
INTRODUCTION AND BACKGROUND
Despite a host of recommendations established by various health organizations for
improving diet and increasing physical activity, the prevalence of obesity has increased
dramatically in the United States during the past two decades. The fattening of America
has spawned a billion dollar weight loss industry, with advertising of diet books, exercise
programs, and supplements offering quick fix remedies to boost metabolism and melt away
fat. Given the confusion, misinformation, and pursuit of the ‘magic bullet’ that
characterizes the weight loss industry in the U.S., it is especially important to identify
approaches to long_term weight loss that are based on sound scientific principles of body
weight regulation.
Body fat stores can be reduced by creating an energy deficit, but severe energy restriction
produced by many fad diets may result in metabolic adaptations that sabotage
maintenance of lost weight. Also many fad diets require the avoidance of ‘favorite foods’,
an approach that can jeopardize dietary adherence. A more realistic approach to body
weight regulation and health is recommended, characterized by an emphasis on smaller
serving sizes without wholesale changes in the types of foods consumed. This approach
could significantly reduce energy intake without perceptions of deprivation, which can
result in rebound eating binges. The portion control approach to weight regulation can
reduce the intake of high energy density foods without eliminating such foods from the
diet. This approach also allows the consumption of a variety of nutritious whole foods
including fresh fruits, vegetables, whole grains, lean proteins, and reduced fat milk.
A novel approach to weight loss and maintenance, the Lifesize Program has surfaced, which
focuses on the use of portion control measuring devices to limit energy intake while
simultaneously allowing the individual to consume their usual foods. The underlying
premise of this program is that by following one’s customary eating patterns, but limiting
2
the quantities of the most energy dense foods by portion control and allowing unlimited
intakes of vegetables, fruits, and low fat dairy, an energy deficit and weight loss will occur
without a sense of ‘dieting’ and food deprivation. While this approach has a strong
theoretical foundation, important questions remain to be answered including the
following:
• How much weight and fat loss will overweight and obese individuals achieve by
following the Lifesize Program for 12 weeks?
• Do individuals who follow the Lifesize portion control approach to food
consumption lower their average daily food intake relative to their usual intake?
What is the magnitude of the average energy deficit that results from following the
Lifesize Program?
• Given the focus on portion control rather than on avoidance of favorite foods, what
will individuals actually choose to eat, and how will the Lifesize Program affect the
nutritional quality of their diets?
• What are the perceptions of the study participants regarding the Lifesize Program?
METHODS
Subjects
A total of 27 individuals (n=22 women, n= 5 men; mean age=40.4+12.2 years; mean BMI=
29.7 +2.6 kg/m2; mean percent body fat = 39.5+7.3%) were enrolled in this 12_week study.
All participants were informed verbally and in writing as to the purpose of the study, and
provided their informed, voluntary consent prior to enrollment in the study. This study
was approved by the Institutional Review Board of Colorado State University.
Experimental Design
Participants were enrolled in a 12_week weight loss program. Prior to enrollment, baseline
data were collected regarding personal health history, previous experience with weight
loss diets, and habitual food intake using 3_day dietary records. Body weight, body
composition, blood pressure, resting metabolic rate, and average daily steps taken using a
pedometer were also measured at baseline. After collection of baseline data, participants
were provided with a 2_hour orientation to the Lifesize Program. At this meeting,
individuals were informed as to the overall principles of the program, were provided with
the Lifesize measuring devices with a detailed explanation as to their use, and were given
the Lifesize training DVD and instructions as to how to use it. Enrolled participants
3
reported to the Nutrition Center at Colorado State University at regular time periods during
the next 12 weeks for follow_up and repeated testing as described below.
Specific Procedures
Preliminary Session 1: Upon obtaining voluntary informed consent, subjects underwent the
following screening tests to determine eligibility.
• Each subject’s height, weight, and BMI were measured using the Tanita Body Fat
Analyzer (Model TBF_105, Tanita Corporation of America, Inc., Arlington Heights, IL).
Subjects were measured without shoes and socks, and wearing light indoor clothing.
Body weight was measured to the nearest 0.1 kg.
• Each subject’s percent body fat was measured using Bioelectrical impedance (BI). This was
completed with the Tanita Body Fat Analyzer mentioned above.
• Health History Questionnaire_ Subjects’ age, health_related habits, and personal and
family health history were measured using a standard health history questionnaire.
Preliminary Session 2
Volunteers reported to the Nutrition and Metabolic Fitness Laboratory in a 12_h fasted state for the
purpose of baseline testing which involved the following tests:
• AnthropometricsAll
anthropometric measures were made under identical
conditions for all subjects during the entire study. Subjects were fasted, consumed
250 ml of water after waking, voided their bladders, and wore only shorts and a tshirt.
Body weight was measured on the same calibrated physicians’ balance scale
to the nearest 0.1 kg. Height without shoes was measured to the nearest 0.1 cm
with a wall_mounted stadiometer. Body mass index was calculated as weight in kg
divided by height in m2.
• Waist, hip, thigh, and upper arm girths were obtained in centimeters using a nonstretchable
measuring tape. The waist circumference was measured at the
umbilicus in men and the natural waistline in women; the hip circumference was
measured at the level of the maximum hip circumference. Bioelectrical impedance
(BI) was used to assess percent body fat using the Tanita Body Fat Analyzer (Model
TBF_105, Tanita Corporation of America, Inc., Arlington Heights, IL). All subjects
were instructed to follow specific manufacturer guidelines for BI testing. Fat free
mass and percent body fat was calculated using prediction equations supplied by
the manufacturer based on weight, age, and impedance index (ht2/z score).
• Resting blood pressure and heart rate were measured using a standard automated
sphygmomanometer (Dynamap) with subjects resting quietly in a sitting position
for 5 minutes. Systolic, diastolic, and mean arterial pressure values were recorded.
• Basal metabolic rate (BMR)_ Subjects arrived at the metabolic fitness laboratory
after a 12_h overnight fast and before engaging in any type of physical activity.
Indirect calorimetry (Parvomedics, Salt Lake City) was used to measure BMR based
on the VO2 and VCO2 measures while the subject lay quietly on a comfortable bed
with a clear plexiglass respiratory canopy over the head for 20 minutes. The
respiratory gas exchange data were converted to kcal expended per minute using
the Weir equation.
4
• Study participants completed 3_day dietary records. A co_investigator monitored
the dietary data entered and verified and corrected discrepancies (e.g. out_of_range
kilocalorie intakes) with participants.
• Pedometers were provided for measuring daily step counts during the entire 12_
weeks of the study. Participants were instructed on how to use the pedometers and
record their daily step counts.
Preliminary Session 3: Study participants attended a group orientation session to learn
about the portion control approach to weight loss. They were given instruction as to how
to follow the program for the 12 weeks, which involved the use of the unique portion
control devices, the DVD, and the wall chart. Participants were also asked to complete a
pre_program questionnaire to assess their knowledge, beliefs, and attitudes about weight
loss and portion size.
The Portion Control Program
Program Week1: After completion of the baseline tests and the orientation session,
participants began the program. The goal of the program was to provide a means of
measuring the amount of food and types of food they should be eating to be healthy and to
lose weight. The program emphasizes limiting the quantities of the most energy dense
foods by portion control and allowing unlimited intakes of vegetables, fruits, and non_fat
milk, which theoretically should result in an energy deficit and weight loss without a sense
of ‘dieting’ and food deprivation. At the end of the first week of the program participants
reported back to the Nutrition Center to meet with the project staff to discuss their
adherence to the program based on 3_day food records and step counter records. Their
body weight, body fatness, heart rate and blood pressure were also measured at this time.
Program Week 2: At the end of the second week of the program participants returned to
the Nutrition Center for further consultation. Body weight, body composition, heart rate
and blood pressure were again measured and participants provided their pedometer
records.
Weeks 412:
After week 2 in the program, participants reported to the Nutrition Center every two weeks
for further consultation and measurement of body weight, body fatness, heart rate and
blood pressure, as well as providing step count records. During week 6 and 12, they also
recorded their food intake for 3 days. The food records were for the purpose of
determining how effective the program is at helping reduce food intake relative to preprogram
values, and also for examining their diets for macro_ and micronutrient intake.
PostProgram
Testing: After participants completed 12 weeks in the program, they
underwent post_intervention testing identical to the preliminary tests: body weight, body
composition, heart rate, blood pressure, basal metabolic rate, and circumference
measurements. They also completed a post_program questionnaire in which they were
asked to report their perceptions of the program regarding ease of adoption, compliance
with the protocol, use of the measuring devices, etc. They were also asked several
5
knowledge questions to determine their level of understanding of the Lifesize approach to
weight loss.
Data analysis: Data were analyzed for dietary intake, anthropometric characteristics,
RMR, and blood pressure using paired t_tests and a within_subjects repeated analysis of
variance with post_hoc comparisons. Statistical significance was established at P<0.05.
Given the pilot nature of this study, a non_intervention control group was not be used.
6
RESULTS
Of the 27 individuals who were enrolled in the study, a total of 23 completed the 12_week
program. The four individuals dropped out for various reasons including lack of time,
pregnancy, moving from the area, and one individual felt unsatisfied with the program.
The physical characteristics of the remaining 23 individuals are provided in Table 1. The
study volunteers were mostly overweight and obese women, with a history of previous
dieting. Resting metabolic rates were not different than predicted based on body size,
indicating that the study subjects did not have unusually low metabolic rates that would
affect their ability to lose weight when energy intake was modestly restricted.
Table 1. Physical Characteristics of Study Participants (n=23) at Baseline Prior to
Implementing the Lifesize Program
Variable Mean (SD)
Age 40 (12)
Height (cm) 169.2 (8.1)
Weight (kg) 86.3 (12.1)
BMI (kg/m2)* 30.0 (2.4)
% Body Fat 38.7 (7.4)
Lean Body Mass (kg) 53.0 (10.9)
Upper Arm (cm) 34 (3)
Waist (cm) 94 (9)
Hips (cm) 113 (7)
Thigh (cm) 58 (4)
BMR (kcal/d)** 1751 (290)
*BMI= Body Mass Index
**BMR=Basal Metabolic Rate
Anthropometric changes: Table 2 provides the data on the changes that occurred in
body weight (also shown in Figure 1) and body composition over the 12 weeks of the
program. The mean weight loss during the 12 week program was 2.24 kg (~5.0 pounds)
with the men losing about twice as much weight as the women (8 pounds versus 4
pounds). There was a small decrease in percent body fat, which did not reach significance.
Table 2. Mean bodyweight and percent body fat in study participants (n=23) at
baseline and
after 12 weeks
of the Lifesize
Program.
Baseline Week 12 Mean Loss
Variable Mean (SD) Mean (SD)
Body Weight (kg) 86.0 (9.7) 83.7 (9.3)* 2.24 (2.25)
% Body Fat 39.7 (7.5) 39.1 (8.2) 0.52 (1.70)
7
*Mean weight loss of 2.24 kg, week 12Figure 1: Changes in weight during the Lifesize program.
Figure 1 illustrates average total weight loss during the Lifesize study. As seen above,
although weight loss was modest, it was consistent throughout the program.
Figure 2: Average changes in circumference measurements for 22 participants. Blue
bars=pre_program; Red bars=post_program.
86.25
85.70 85.82
85.26 85.13
84.56
84.30
83.90 83.95
82.50
83.00
83.50
84.00
84.50
85.00
85.50
86.00
86.50
Pre
Program
Baseline Week 1 Week 2 Week 4 Week 6 Week 8 Week 10 Post
Weig
ht
(
kg)
Change in Weight
94.3 91.4
113.4 111.6
58.5 57.4
34.4 33.7
20.0
40.0
60.0
80.0
100.0
120.0
cm
Circumference Measurements
8
In accordance with the modest weight loss that occurred during the program, there was a
significant decrease in the sum of the waist, hip, thigh, and arm circumference
measurements of 6.5 + 7.1 cm (p<0.01) from pre_program (baseline) measures compared
to those obtained at the end of the program.
Figure 3. Pre_ and post_program basal metabolic rates for the Lifesize study participants.
There was a decrease of approximately 125 kcal in basal metabolic rate over the 12 weeks
of the program. This decrease was expected with the modest weight loss that was
achieved.
Changes in calorie and macronutrient intakes: Table 3 provides information regarding
the changes in energy and macronutrient intake based on 3_day dietary records that were
reported during the 12 weeks. The decrease in self_reported average daily energy intake
relative to the pre_program baseline energy intake was on the order of 400_500 kcal per
day for weeks 1, 6, and 12. The decrease in reported energy intake was fairly consistent
across the entire 12 weeks of the program. The decline in energy intake was reflected by
decreased intakes of all three macronutrients—protein, carbohydrate, and total fat. At
least a portion of the total reduction in dietary carbohydrates during the Lifesize Program
was due to a significant reduction in sugar intake. Dietary saturated fat intake was also
reduced from pre_program and baseline compared to intake at weeks 1,6, and 12. There
was no significant reduction in dietary cholesterol. Dietary fiber intake in grams was also
1751.41
1624.45
1000.00
1100.00
1200.00
1300.00
1400.00
1500.00
1600.00
1700.00
1800.00
Pre Post
kcals/24hrs
Basal Metabolic Rate
9
reduced at weeks 1, 6, and 12 relative to the pre_program values; however there were no
changes in fiber intake relative to total calorie intake from pre_program to week 12.
Table 3. Mean energy and macronutrient intakes of study participants before
implementing the Lifesize Program and during weeks 1, 6, and 12 of the Program.
a denotes statistically significant difference from pre program, p< 0.05
b denotes statistically significant difference from Week 1, p<0.05
Table 4. Mean intakes of specific micronutrients in the study participants before
implementing the Lifesize Program and during weeks 1, 6, and 12 of the Program.
a denotes statistically significant difference from pre program, p< 0.05
Pre_Program Week 1 Week 6 Week 12
X (SD) X (SD) X (SD) X (SD)
Total Kcal/d 2177 (520) a1680 (368) a1608 (331) ab1510 (176)
Protein (g/d) 89.9 (26.5) a73.8 (19.7) 73.8 (23.5) a74.3 (15.5)
% of kcal 16.4 (2.4) 17.4 (3.3) a19.1 (4.2) ab19.5 (3.8)
CHO (g/d) 257.5 (75.7) a200.3 (52.2) a196.3 (54.6) a185.5 (42.5)
% of kcal 46.6 (7.1) 47.3 (6.8) 47.7 (7.2) 48.2 (7.9)
Sugar (g/d) 95.5 (40.4) a76.9 (26.8) a71.0 (26.6) a67.5 (25.0)
Fat (g/d)* 88.2 (25.1) a63.4 (18.3) a57.9 (16.3) ab53.1 (9.4)
% of kcal* 36.3 (5.6) 33.6 (6.5) a32.0 (7.1) a31.4 (5.4)
Sat Fat (g/d)* 28.3 (8.9) a19.5 (8.0) a20.0 (6.2) a17.0 (5.2)
% of kcal 11.9 (3.0) a10.3 (3.1) b11.0 (3.1) a10.1 (2.7)
Cholesterol (mg/d) 267.7 (127.5) 251.4 (107.7) 242.2 (97.3) 240.8 (86.6)
Fiber (g/d) 23.2 (8.5) a18.9 (7.1) a18.3 (4.9) a17.2 (6.4)
Fiber (g/1000kcal) 10.7 (3.0) 11.3 (3.6) 11.5 (2.9) 11.4 (3.9)
Pre Program Week 1 Week 6 Week 12
X (SD) X (SD) X (SD) X (SD)
Sodium (mg/d) 3712.3 (1562.0) a2626.2 (922.9) a2570.2 (1042.5) a2252.2 (710.5)
Vitamin A
(RE/d) 900.0 (634.6) 1051.0 (845.2) 879.2 (561.0) 948.9 (797.3)
__
Carotene(ug/d) 2172.8 (2986.7) 3022.8 (3974.3) 2887.3 (4199.2) 2834.2 (4083.2)
Vit C (mg/d) 94.2 (65.5) 98.7 (65.6) 82.9 (40.2) 67.5 (45.6)
Iron(mg/d) 17.5 (8.7) a14.3 (8.6) a13.9 (4.3) a12.1 (4.0)
Calcium(mg/d) 908.6 (284.4) a725.5 (294.8) a764.7 (239.3) a734.0 (240.8)
10
Changes in micronutrient intakes: Table 4 shows the changes that occurred in specific
vitamins and minerals from self_reported pre_program values taken from 3_day dietary
records for those reported at weeks 1, 6, and 12 of the Lifesize Program. There were
significant reductions in sodium intake from baseline (pre_program) at weeks 1, 6, and 12.
Despite the decrease in reported food intakes during the program, there were not
significant reductions in vitamin A, B_carotene, and ascorbate (vitamin C). However, there
were significant decreases in iron and calcium at weeks 1, 6, and 12 relative to preprogram
intakes.
Change in water, vegetables, fruit and lowfat
dairy: Table 5 shows the changes that
occurred in water, vegetables, fruit and low_fat dairy intake based on 3_day dietary records
reported prior to the start of the program and at weeks 1,6,and 12 of the Lifesize Program.
Vegetable and fruit consumption increased at week 1, 6, and 12 of the Lifesize Program.
However, this increase was only statistically significant at weeks 1 and 6 and when
vegetable and fruit intake was calculated relative to total energy intake. The percent of
low_fat dairy relative to total dairy intake also increased throughout the program. This
increase was found to be statistically significant at week 6. Despite continually
emphasizing the importance of increased water consumption, there was no significant
change in water intake.
Table 5: Mean intakes of water, vegetables, fruit, and lowfat
dairy in the study
participants before implementing the Lifesize Program and during weeks 1, 6, and 12
Baseline Week 1 Week 6 Week 12
X SD X SD X SD X SD
Water (g/d) 920.5 (568.1) 809.5 (757.8) 848.4 (664.1) 914.9 (657.8)
Vegetables (g/d) 97.8 (89.7) a213.7 (184.0) 157.7 (126.1) 215.7 (308.9)
Vegetable (
g/1000Kcal) 48.3 (48.4) a125.8 (116.9) a96.61 (69.2)
155.5 (245.9)
Fruit (g/d) 132.7 (106.7) 182.5 (117.8) 149.8 (90.9) 199.8 (270.9)
Fruit ( g/1000Kcal) 61.5 (47.6) a109.9 (68.7) a95.9 (59.0) 137.19 (194.1)
Low_Fat Dairy (g/d) 187.6 (199.5) 157.1 (203.7) 193.1 (149.5) 178.8 (151.8)
Low_Fat Dairy (
g/1000Kcal) 87.83 (93.29) 87.89 (112.5) ab127.9 (107.11) 115.4 (95.2)
11
Percent of Dairy as
Low_Fat Dairy (%) 61.0 (42.8) 61.7 (45.2) ab80.9 (33.8) 77.0 (37.6)
a denotes statistically significant difference from pre program, p< 0.05
b denotes statistically significant difference from Week 1, p<0.05
There were no differences in the average daily number of steps recorded from pedometer
counts from pre_program (x=8950 steps/d) to week 12 (x=8800 steps/d).
Knowledge and Perceptions of the Participants in the Lifesize Program: After 12
weeks of the Lifesize Program participants completed a questionnaire (see appendix), in
which they were asked to report their perceptions about the program relative to their
expectations. The graphs below represent the response percentages of individuals to each
of the questions. Two participants that had dropped out of the program also completed a
questionnaire, increasing the n for questionnaire responses to 25 for most questions. Not
everyone answered the questionnaire in its entirety, therefore some figures report
different total n values, and they are noted below the figure.
Figure 4
*n=24 for this question
The results of this question show that 56 percent of participants were somewhat or
extremely happy with their weight loss. Referring to the open comments from participants,
further explanation as to the factors that affected their satisfaction are apparent. Some
participants stated that even though they did not lose as much weight as they wanted, they
were happy because it wasn’t a restrictive program and they could still eat the foods that
they enjoy.
12
Figures 5,6 and 7 show responses to questions about the usefulness of Lifesize supporting
materials. Overall, participants found the CDs, DVD and wallchart to be helpful. Most
(59%) only watched the DVD one time, and did not refer back to it.
Figure 5
Figure 6
Figure 7
n= 3
n= 4
n= 11
n= 7
0%
10%
20%
30%
40%
50%
Strongly Disagree Somewhat
Disagree
Somewhat Agree Strongly Agree
"I found the Lifesize CDs to be very
helpful."
n= 1
n= 16
n= 5
n= 3
0%
10%
20%
30%
40%
50%
60%
70%
Watched and
referred back
Watched and
didn't go back
Jumped around Didn't use
"Which statement describes your use
of the DVD?"
13
Figure 8
Figure 9
n= 0 n= 1
n= 6
n= 18
0%
20%
40%
60%
80%
Strongly disagree Somewhat
disagree
Somewhat agree Strongly agree
"I found the Lifesize wall chart to be
very helpful."
n= 0
n= 1
n= 10
n= 14
0%
10%
20%
30%
40%
50%
60%
Extremely difficult Somewhat difficult Somewhat easy Extremely easy
"How difficult or easy was it to use the
Lifesize portion control devices?"
14
Figures 8 and 9 refer to the portion control devices themselves. Figure 8 shows that 89
percent of participants believed the devices were easy to use. Figure 9 shows that 70
percent believed the devices were easy to incorporate into their lifestyle.
Figure 10
*n=23 for this question
n= 0
n= 6
n= 15
n= 4
0%
20%
40%
60%
80%
Extremely
inconvenient
Somewhat
inconvenient
Somewhat
convenient
Extremely
convenient
"How inconvenient or convenient was
it to incorporate the portion control
devices into your lifestyle?"
n= 13
n= 10
0%
10%
20%
30%
40%
50%
60%
Yes No
"Did you know what Lifesize meant
by the phrase: It is a complete 5 step
program?"
15
Figure 11
Figure 12
n= 0
n= 3
n= 11 n= 11
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
50%
Extremely difficult Somewhat
difficult
Somewhat easy Extremely easy
"How would you describe the
difficulty or simplicity of following
the Lifesize program as a whole?"
16
Figures 11 and 12 refer to questions regarding the difficulty or simplicity of the Lifesize
program. When looking at the program as a whole, 81 percent responded that the program
was somewhat or extremely easy. However, when looking at the simplicity of the program
while dining out or away from home, that number dropped to only 59 percent finding the
program somewhat or extremely easy.
Figures 13 and 14 refer to the questions regarding the number and sizes of Lifesize
portions. When looking at the size of the portions, 70 percent of participants agreed that
the size of the portions was appropriate for weight loss. Looking at the number of Lifesize
portions, 70 percent believed that the number of portions were appropriate for weight loss.
Figures 19 and 20 provide more information regarding the number of Lifesize portions.
Figure 13
n= 0
n= 9
n= 13
n= 3
0%
10%
20%
30%
40%
50%
60%
Extremely difficult Somewhat
difficult
Somewhat easy Extremely easy
"How would you describe the
difficulty or simplicity of using your
knowledge of Lifesize portion sizes to
choose portions of food while dining
out or away from home?"
17
Figure 14
Figure 15
n= 2
n= 4
n= 12
n= 7
0%
10%
20%
30%
40%
50%
60%
Strongly disagree Somewhat
disagree
Somewhat agree Strongly agree
"The Lifesize portion sizes were
appropriate for weight loss for me."
18
Figure 16
19
Figure 17
*n=22 for this question
Figure 18
Figures 15 through 18 represent the questions concerning changes in consumption of
fruits, vegetables, low fat dairy and water throughout the Lifesize program. Looking at
20
these responses, 66 percent of participants stated they increased their intake of fruit, 74
percent stated they increased consumption of vegetables, 33 percent stated they consumed
more low fat dairy, and 64 percent stated they increased the amount of water they
consumed throughout the study. Almost 15 percent of participants believed they
consumed less lowfat dairy, while only about 4 percent said they consumed less fruit,
vegetables or water.
Figure 19
*n=24 for this question
Figure 20
*n=24 for this question
Figures 19 and 20 address the questions about deviation from the Lifesize program.
Approximately 80 percent of participants reported deviating from the program by eating
n= 6 n= 7 n= 6 n= 5
0%
10%
20%
30%
40%
Zero to two times Three to seven times Seven to eleven times Twelve or more times
"During the 12 weeks, on how many occasions
did you deviate from the Lifesize portion control
approach by consuming significantly larger
quantities of food?"
n= 3
n= 9
n= 8
n= 4
0%
10%
20%
30%
40%
Zero to two times Three to seven times Seven to eleven times Twelve or more times
"During the 12 weeks, on how many occasions
did you deviate from the Lifesize portion control
approach by consuming significantly lower
quantities of food?"
21
larger quantities of food, with the most responses (26 %) being in the range of three to
seven occasions during the program. When looking at deviation by eating smaller
quantities of food, 90 percent of participants reported some deviation, with 60 percent
reporting that they deviated on three to eleven occasions throughout the study. This
correlates with the finding that 22 percent of participants believed that the number of
allotted portions was not appropriate for them.
Figure 21
Figure 22
*n=23 for this question
n= 4
n= 11
n= 6
n= 2 n= 2
0%
20%
40%
60%
Always Most of the time Sometimes Rarely Never
"During the first 6 weeks of the Lifesize
program,if you were still hungry immediately
after finishing a meal, how often did you wait 15
minutes before getting a second helping of
food?"
n= 6
n= 4
n= 6
n= 5
n= 2
0%
10%
20%
30%
Always Most of the time Sometimes Rarely Never
During the last 6 weeks of the Lifesize program, if
you were still hungry immediately after finishing
a meal, how often did you wait 15 minutes
before getting a second helping of food?"
22
Figures 21 and 22 refer to questions regarding the “wait 15 minutes” concept of the
Lifesize program. During the first 6 weeks, 55 percent of participants said that they waited
15 minutes most of the time or always before getting a second helping of food. During the
last 6 weeks, that number dropped to 37 percent.
Figure 23
Figure 24
*n=23 for this question
n= 9
n= 13
n= 1
n= 2
0%
10%
20%
30%
40%
50%
60%
Strongly disagree Somewhat disagree Somewhat agree Strongly agree
"During the first 6 weeks of the study, I
often felt deprived of eating my favorite
foods."
n= 9
n= 12
n= 0
n= 2
0%
10%
20%
30%
40%
50%
60%
Strongly disagree Somewhat disagree Somewhat agree Strongly agree
"During the last 6 weeks of the study, I
often felt deprived of eating my favorite
foods."
23
Figures 23 and 24 refer to feelings of deprivation during the program. During the first 6
weeks, only 11 percent of participants indicated that they felt deprived of eating their
favorite foods. During the last 6 weeks, this number dropped to about 7 percent. These
values are typically well below any reported percentage of feelings of deprivation in other
weight loss programs.
Figure 25
Figure 26
*n=23 for this question
n= 1 n= 1
n= 8
n= 15
0%
10%
20%
30%
40%
50%
60%
70%
Zero to twenty_ five
percent
Twenty_six to fifty
percent
Fifty_one to seventyfive
percent
Seventy_six to one
hundred percent
"During the first 6 weeks, I would
estimate my compliance with the
program to be:"
n= 1
n= 3
n= 12
n= 7
0%
10%
20%
30%
40%
50%
60%
Zero to twenty_five
percent
Twenty_six to fifty
percent
Fifty_one to seventyfive
percent
Seventy_six to one
hundred percent
"During the last 6 weeks, I would
estimate my compliance with the
program to be:"
24
Figures 25 and 26 give information concerning the participants’ perception of their
compliance with the Lifesize program. These graphs demonstrate that compliance was
greater during the first 6 weeks of the program compared to the last 6 weeks.
Figure 27
Figure 28
*n=23 for this question
Figures 27 and 28 deal with responses to questions asking what percentage of food was
measured using the devices and natural portion guidelines. During the first 6 weeks, 85
n= 0
n= 2
n= 13
n= 10
0%
10%
20%
30%
40%
50%
60%
Zero to twenty_five
percent
Twenty_six to fifty
percent
Fifty_one to seventy_five
percent
Seventy_six to one
hundred percent
During the first 6 weeks, the percentage of food
I ate using the devices/natural portions was:"
n= 3
n= 6
n= 10
n= 4
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
50%
Zero to twenty_five
percent
Twenty_six to fifty
percent
Fifty_one to seventy_five
percent
Seventy_six to one
hundred percent
"During the last 6 weeks, the percentage of food
I ate using the devices/natural portions was:"
25
percent of participants said they used them at least half the time. During the last six weeks,
only about 50 percent of participants stated that they used the devices/natural portions
more than half the time.
Figure 29
Figure 30
CSU staff was found to be helpful by 90 percent of participants, and knowledgeable by 85
percent.
n= 0 n= 0 n= 1
n= 24
0%
20%
40%
60%
80%
100%
120%
Strongly disagree Somewhat disagree Somewhat agree Strongly agree
"I found the CSU staff to be very helpful."
n= 0 n= 0
n= 2
n= 23
0%
20%
40%
60%
80%
100%
Strongly disagree Somewhat disagree Somewhat agree Strongly agree
" I found the CSU staff to be very
knowledgeable."
26
DISCUSSION
This study was designed to address specific questions regarding the Lifesize portion
control approach to weight loss.
Question 1: How much weight and fat loss will overweight and obese individuals
achieve by following the Lifesize Program for 12 weeks?
The major finding of this study is that the average weight loss for overweight and mildly
obese individuals was approximately 5 pounds, with the four men losing an average of 8.5
pounds and the 19 women losing an average of about 3.9 pounds. The men had higher
body weights and resting metabolic rates compared to the women, and thus were more
likely than the women to create a greater energy deficit on the Lifesize Program, which
uses a fixed number of portions for all participants. This finding is not unexpected as men
typically lose weight more readily than women owing to greater daily energy expenditure.
As the investigators have discussed with the inventors of Lifesize, weight loss would be
predicted to be quite variable across study participants, given that the number of portions
allowed with Lifesize is constant, regardless of the individual’s initial body weight and
energy requirements.
The magnitude of the reduction in body fat was small and did not reach statistical
significance. However, the method used in this study, bio_impedance analysis, is not the
gold standard and was likely lacking adequate resolution to identify small changes in total
body fat. We used a second approach to indirectly measure weight and fat loss using
circumference measurements of the waist, hips, thigh, and arm. There was a statistically
significant reduction in the sum of these girth measurements.
Question 2: Do individuals who follow the Lifesize portion control approach to food
consumption lower their average daily food intake relative to their usual intake?
What is the magnitude of the average energy deficit that results from following the
Lifesize Program?
While on the Lifesize Program, the subjects reportedly reduced their daily energy intake an
average of 400_500 kcal per day based on their three day records. The energy intake while
using the measuring devices was fairly constant for weeks 1,6, and 12, indicating the
sustainability of this approach to lowering energy intake. The magnitude of the reported
energy deficit over the 12 weeks would have predicted a greater weight loss. However, as
expected, there was an average decrease in basal metabolic rate by approximately 100 kcal
after 12 weeks on the program. This is a common finding in weight loss studies. Also, it is
well recognized that study participants who are expected to lose weight by lowering their
energy intake, often under report their food intake when asked to provide this information.
Thus, the lower actual weight loss compared to what would be predicted based on the
magnitude of the reported reduction in food and energy intake, is not surprising.
27
Question 3: Given the focus on portion control rather than on avoidance of favorite
foods, what will individuals actually choose to eat, and how will the Lifesize Program
affect the nutritional quality of their diets?
The dietary quality data as determined from the 3_day food records, suggest that the study
participants changed the amount of food ingested rather than changing the types of foods
consumed. There were decreases in the absolute amounts of carbohydrates, proteins, and
fats consumed which reflects a reduction in total food intake rather than targeted
reduction only of specific high fat, high sugar, or “forbidden” foods. This notion is further
substantiated by the lack of significant decreases in the percentages of these
macronutrients consumed relative to calories, suggesting that individuals were in fact just
lowering their food intake without attempting to specifically lower their intakes of fat or
carbohydrates. This would be expected given the emphasis that the Lifesize approach
places on portion control while eating foods that one enjoys.
There were reductions in sodium intake, which likely reflects a reduction in nondiscretionary
sodium found in foods. In other words, if individuals consumed smaller
portions of food, most of which contained at least some sodium, the intake of this mineral
was necessarily reduced. Similar findings were also found for iron and calcium. The latter
finding was somewhat surprising, as dairy products provide approximately 75% of the
dietary calcium for most Americans. Given the use of low_fat milk products as free foods,
which the study participants could freely consume, we hypothesized that dietary calcium
would increase, even in the face of a reduction in calories. This was apparently not the
case.
Fruits and vegetables are also ‘free’ foods in the Lifesize Program; thus we hypothesized
that participants would exhibit increased fruit and vegetable intakes. The responses to the
final questionnaire showed that the majority of individuals reported increases in
consumption of these foods. Additionally, based upon the 3_day dietary records we found
that fruit and vegetable intake increased relative to calories consumed. This phenomenon
should in turn be reflected by increased dietary intakes of vitamin C and beta_carotene.
However, the intakes of these nutrients did not increase as determined by the 3_day dietary
records. The reason for this discrepancy could be related to the types of fruits and
vegetables consumed, wherein study participants increased their intakes of fruits such as
apples, pears, and bananas which are not rich sources of vitamin C and beta_carotene.
Question 4: What are the perceptions of the study participants regarding the Lifesize
Program?
The participants’ responses to the final questionnaire used to address this question
revealed some interesting findings. The majority of the participants were at least
somewhat happy with their weight loss, although some clearly expected larger amounts of
body weight loss than they achieved. We might recommend that a smaller number than 6
portions, possibly only 4 or 5 portions depending on the person’s goals, be allowed initially
28
to ‘jump start’ the weight loss. Then the current approach using 6 portions could be used
for slower weight loss later in the program and also for weight maintenance.
The majority of the participants seemed to understand the essence of the Lifesize approach,
and found the DVDs and wall charts to be helpful. Most participants stated that they only
watched the DVD once, and did not refer back to them. This may be useful to know for
future evaluation of the resource materials. Why some individuals did not find the
materials helpful is unclear. The majority of participants found the devices easy and
convenient to use, more so when eating at home than when dining out.
Participant Comments to OpenEnded
Questions Asked Upon Program Completion:
The respondents were asked to provide open_ended comments at the end of the program,
and these are provided below as brief summaries and the individual comments.
QUESTION: Please Tell Us Briefly Why You Are Happy Or Unhappy With Your Weight
Loss.
10 participants stated that they were unhappy with their weight loss. They stated that they
were unhappy because they would have liked to lose, or had expected to lose more weight.
But half of those cited life events as the reasons they didn’t lose weight. 11 participants
stated that they were happy with their weight loss. They stated that even a few pounds
made a difference in how they felt, they experienced health benefits, such as a decrease in
reflux, and that they only had to make minor changes to the food and drinks they already
ate. They said they experienced healthy weight loss, and learned how to eat better foods
and control amounts taken at each meal.
“I am happy I found a program that is practical but not life altering to use.”
DID YOU WANT OR NEED TO SEE FASTER WEIGHT LOSS
17 participants said yes, they wanted faster weight loss. But some commented that they
understood why the weight loss was slower. 4 participants stated that they didn’t want
faster weight loss.
IF YOU HAD TO DESCRIBE LIFESIZE IN 3 SENTENCES, WHAT WOULD THEY BE?
*It’s simple. It’s user friendly. It’s a solo program.
*It trains you to eat the right amount. You can still eat balanced. It’s a long term plan not a
quick weight drop.
*You can eat what you want, just not as much as you think you need. It is simple and
straight forward. You can always be drinking more water.
*No counting calories, carbs, point, etc. Fairly simple to follow. Effective if program is
followed.
*It provides a new perspective on eating. It promotes well_being. It’s not a “diet”, it’s a
lifestyle.
*Easy portion control system. Allows you eat what you like. Helps add fruits and veggies to
the diet.
*Realistic. Portion control. Exercise.
29
*Safe way to lose weight. It helps you portion food without being deprived. I think it is a
practical
program for everyday life.
*Easy to use and understand. Never feel deprived. Gives you the power to stay in control.
*Portion control. Portion control. Portion control.
*Lifesize uses portion sizes to lead to weight loss. Lifesize uses number of portions to lead
to weight loss. Lifesize lets you eat any food you want.
*Portion control. Begin with water. Wait 20 minutes. Free foods are a good thing.
*Portion control. Limit number of portions. Don’t go hungry, fill up on healthy choices.
*It’s all about moderation so you can eat what you like. It teaches you how to portion food
reasonably without counting calories. It’s fairly easy to use with the tools they give you.
HOW IS LIFESIZE DIFFERENT FROM OTHER DIET PROGRAMS?
The participants said unanimously that it is not restrictive, they felt they could eat what
they wanted, and that it was more of a lifestyle change than a diet. They all understood that
the focus of the program was portion control. A few mentioned that the devices and wall
chart made it simple.
“Because you don’t go without your favorite foods, just learn how to eat correct amounts.”
WHAT DIDN’T YOU LIKE ABOUT THE PROGRAM?
Most participants stated that the program was harder to follow when eating away from
home and on vacation. Some participants said the program was actually too simple, that
there weren’t enough examples of typical restaurant choices or combo meals, and that
there weren’t a lot of ethnic foods discussed. Some participants stated that the portions
were too large, and that they felt they were adding in food to get all 6 portions in.
Participants stated that they thought the program should be more individualized, that
there wasn’t any emotional support for overeating/emotional issues related to eating, and
that because it was very simple, it was easy to go back to having larger portions by
accident.
DOES LIFESIZE WORK?
Seventeen participants agreed that the program works. They felt it worked because they
didn’t feel deprived and they had freedom to eat what they wanted. Most felt that it
worked because they realized the importance of portion sizes. Six participants that stated
that the program doesn’t work stated so because it wasn’t individualized, it doesn’t address
what they were eating, or why they might be overeating, and that the program should
reinforce the importance of exercise. They stated that they found themselves making poor
nutrition choices because there was no structure.
“Yes, because it allows a person to still enjoy food, but understand the need for
moderation.”
ADDITIONAL COMMENTS:
*Needs to have some form of support: online or group.
30
*Learning portion control has had health benefits beyond weight loss. Prior to participating
I had terrible reflux problems. I have not needed medication for that since about the
second week. I’ve also learned what it truly feels like when my body needs food and when I
am full. Overall this has been a good learning experience. I think the counseling and
guidance component of the experiment has been beneficial. I am not sure that someone
using the program without it will be as successful or satisfied.
*I think calories are slightly overlooked. Some portion sizes seemed to have much higher
calories than others. 3 slices of pizza pack a lot more calories than a lifesize portion of
grilled chicken breast, yet they count the same. And pizza is a whole lot easier than grilling
chicken. I tended to stray towards the easy “big” portions that probably gave me more
calories than I needed.
*The videos were helpful, however they showed the same food items over and over. It
would have been nice to see more variety to give me a better idea, instead of just mac and
cheese and steak.
*Being able to eat as much fruit as I wanted was a down fall for me.
*If there was an interactive program online that could be used in tandem with Lifesize, I
could see it being beneficial.
*Travel size wall chart would be great.
*There should be a square dessert measurement tool along with the pie shape. Most cakes,
brownies and cobblers are in square servings.
*Foods like sushi and crystal light should be included in the chart. Otherwise, THANK YOU!
*The portions were sometimes bigger than what I would normally eat. I think the pizza and
hotdog portions should be smaller.
*I see lifesize as working for maintenance, but not really as a weight loss program. I also
don’t agree with some of the portion sizes. For example: I don’t think a granola bar,
especially a 90 calorie one, should count as two portions.
* I think exercise could be emphasized more. THANK YOU!!
*I am glad I attended the lifesize program. Not only because I lost about 5 kg but also
because I know I can lose my weight in a healthy way even if I don’t have a lot of time for
exercise.
*It can be a little difficult to compare natural portion size for food that is not listed.
*didn’t change “what” to eat.
*Controversy over diet soda.
*The scoop versus portion idea confused me a lot.
31
ID: _______________________________/____________/__________
Last four digits of your phone number/month of birth/day of birth
Post-Program Questionnaire
Introduction: Thank you for your participation in the Lifesize program. As part of the evaluation
process for the program, we are asking that you complete this post-program questionnaire. This
questionnaire is designed to gain feedback on changes in your attitudes about diets and your eating
behaviors as a result of the Lifesize program. The information obtained in this questionnaire will be
confidential.
Goal: To determine weight loss satisfaction on the Lifesize program.
First tell us about your weight loss results during the Lifesize program.
1. How much weight did you lose during the 12 week program? ______ (lbs)
2. When you enrolled in the study, how much weight did you hope to lose? _____ (lbs)
3. Are you happy with the amount of weight you lost during the 12 week program?
extremely unhappy somewhat unhappy somewhat happy extremely
happy
4. Please tell us briefly why you are happy or unhappy with your weight loss. ________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
5. Did you want or need to see faster weight loss?______________________________________
Now we would like to ask you questions about components of the Lifesize program.
1. I found the Lifesize CDs to be very helpful.
strongly disagree somewhat disagree somewhat agree strongly agree
2. Which one of the statements below best describes your use of the DVD?
I watched it all the way through once and later referred back to all or parts of it as I needed to.
I watched it all the way through once, but did not refer back to it.
I did not watch the entire DVD, but jumped around to find bits and pieces of important info.
I didn’t use the DVD.
3. I found the Lifesize wall chart to be very helpful.
strongly disagree somewhat disagree somewhat agree strongly agree
4. Did you understand the "Quick Start" chart? Yes No
5. How difficult or easy was it to use the Lifesize portion control devices?
extremely difficult somewhat difficult somewhat easy extremely easy
6. How inconvenient or convenient was it to incorporate the portion control devices into your lifestyle?
32
extremely somewhat somewhat extremely
inconvenient inconvenient convenient convenient
Now we would like to know your thoughts about the statements below.
(Please mark an X for your level of agreement with the following statements.)
Strongly
Disagree
Disagree Neutral Agree Strongly
Agree
1. I have to give up my favorite high fat/high
sugar foods to lose weight.
2. I need to increase my activity and/or
exercise to lose weight.
3. I think that having my family/roommate(s)
eat the same foods as me would help with
my weight loss.
4. I won’t stay on a weight loss program when
I feel deprived.
5. I expect to feel deprived on a weight loss
program.
6. I will eat a food that is not on my program
when I feel deprived.
Now we would like to ask you specific questions about the first 6 weeks of the Lifesize Program.
1. During the first 6 weeks of the Lifesize Program, if you were still hungry immediately after finishing
a meal, how often did you wait 15 minutes before getting a second helping of food?
Always Most of the Time Sometimes Rarely Never
2. During the first 6 weeks of the study, I often felt deprived of eating my favorite foods.
strongly disagree somewhat disagree somewhat agree strongly agree
3. During the first 6 weeks of the study, the percentage of food I ate using the devices/natural portions
was:
0-25% 26-50% 51-75% 76-100%
4. During the first 6 weeks, I would estimate my compliance with the program (how closely I followed
the program) to be:
0-25% 26-50% 51-75% 76-100%
5. During the first 6 weeks of the Lifesize Program, how often did you portion out your food before
you ate it? (Please mark an X in only one box for each meal)
33
Never 1-2 times/week 3-4 times/week 5-6 times/weeks Every day
Breakfast
Lunch
Dinner
Snack
6. During the first 6 weeks of the Lifesize Program, how often did you drink water before the following
meals? (Please mark an X in only one box for each meal)
Never 1-2 times/week 3-4 times/week 5-6 times/weeks Every day
Breakfast
Lunch
Dinner
Snack
7. During the first 6 weeks of the Lifesize program, how much of each beverage did you drink
throughout the day? (Please mark an X in only one box for each beverage. If a beverage you
drink is not listed, write it in on the line contained in the last box.)
Less than 1 serving 1-3 servings 4-6 servings 7-9 servings 9+ servings
Water
Low Fat/skim Milk
Whole Milk
Juice
Regular Soda
Beer /Wine/Spirits
Other (please write in
the beverage)
_______________
34
Now we would like to ask you specific questions about the last 6 weeks of the Lifesize Program.
1. During the last 6 weeks of the Lifesize Program, if you were still hungry immediately after finishing
a meal, how often did you wait 15 minutes before getting a second helping of food?
Always Most of the Time Sometimes Rarely Never
2. During the last 6 weeks of the study, I often felt deprived of eating my favorite foods.
strongly disagree somewhat disagree somewhat agree strongly agree
3.During the last 6 weeks of the study, the percentage of food I ate using the devices/natural portions
was:
0-25% 26-50% 51-75% 76-100%
4. During the last 6 weeks, I would estimate my compliance with the program (how closely I followed
the program) to be:
0-25% 26-50% 51-75% 76-100%
5. During the last 6 weeks of the Lifesize Program, how often did you portion out your food before you
ate it? (Please mark an X in only one box for each meal)
Never 1-2 times/week 3-4 times/week 5-6 times/weeks Every day
Breakfast
Lunch
Dinner
Snack
6.During the last 6 weeks of the Lifesize Program, how often did you drink water before the following
meals? (Please mark an X in only one box for each meal)
Never 1-2 times/week 3-4 times/week 5-6 times/weeks Every day
Breakfast
Lunch
Dinner
Snack
7. During the last 6 weeks of the Lifesize program, how much of each beverage did you drink
throughout the day? (Please mark an X in only one box for each beverage. If a beverage you
drink is not listed, write it in on the line contained in the last box.)
35
Less than 1 serving 1-3 servings 4-6 servings 7-9 servings 9+ servings
Water
Low Fat/skim Milk
Whole Milk
Juice
Regular Soda
Beer /Wine/Spirits
Other (please write
in the beverage)
_______________
Now we would like to ask you some questions about changes in your eating patterns and the
Lifesize program.
In the chart below, please consider your consumption of these foods during the Lifesize Program as
compared to before you started. (Mark an X in only one box for each food column that best
describes your intake of that food.)
Fruit Vegetables Low-fat/nonfat
dairy
Water
I consumed less during the Lifesize
Program
I consumed the same amount during
the Lifesize Program
I consumed slightly more during the
Lifesize Program (1-2 servings/day
increase)
I consumed substantially more
during the Lifesize Program (3 or
more servings/day increase)
1. How would you describe the difficulty or simplicity of following the Lifesize program as a whole?
extremely difficult somewhat difficult somewhat easy extremely easy
2. How would you describe the difficulty or simplicity of using your knowledge of Lifesize portion sizes
to choose portions of food while dining out or away from home?
extremely difficult somewhat difficult somewhat easy extremely easy
3. The Lifesize portion sizes were appropriate for weight loss for me.
36
strongly disagree somewhat disagree somewhat agree strongly agree
4. The number of Lifesize portions used per day was appropriate for weight loss for me.
strongly disagree somewhat disagree somewhat agree strongly agree
5. During the 12 weeks, on how many occasions did you deviate from the Lifesize portion control
approach by consuming significantly larger quantities of food?
0-2 occasions 3-7 occasions 7-11 occasions 12 or more occasions
6. During the 12 weeks, on how many occasions did you deviate from the Lifesize portion control
approach by consuming significantly lower quantities of food?
0-2 occasions 3-7 occasions 7-11 occasions 12 or more occasions
7. After a few weeks on the program, I felt comfortable with the Lifesize portions and didn’t need to use
the devices constantly.
strongly disagree somewhat disagree somewhat agree strongly agree
8. Did you understand how and why the Lifesize program suggested that you drink a lot of water?
Yes No
9. Did you know what Lifesize meant by "It is a complete 5 step program”? Yes No
10. If you had to describe LifeSize to a friend in 3 sentences, what would they be?
1._____________________________________________________________________________
_____
2.
__________________________________________________________________________________
3.
__________________________________________________________________________________
11. In a sentence, how is LifeSize different from other diet programs?
_____________________________________________________________________________________
______
12. What didn't you like about the program?
_______________________________________________________________
_________________________________________________________________________________________________________
____
13. In a sentence, does LifeSize work ? (Why or Why not?)
_______________________________________
_____________________________________________________________________________________
___
14.I found the CSU staff to be very helpful.
strongly disagree somewhat disagree somewhat agree strongly agree
15. I found the CSU staff to be very knowledgeable.
strongly disagree somewhat disagree somewhat agree strongly agree
37
Please provide any additional comments about the Lifesize program in the box below.
Thank You