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United States Department of Agriculture

Agricultural Research Service

Dietary Glutamate, Weight Loss and Body Health Study for Women

 

Who is conducting this study?

The study is conducted by Kevin Laugero, PhD and Nancy Keim, PhD, RD. The study has been reviewed and approved by the UC Davis Committee for the Protection of Human Studies. There is only minimal health risk associated with participation in this study.

 

What is the purpose of the study?

The study is being done to learn more about the effect of monosodium glutamate (MSG) on body weight and factors that may affect body weight.

 

Who can participate?

Healthy women, 19 to 50 years of age, who are approximately 16 - 90 pounds overweight, depending on height, (BMI between 27 – 39.9 kg/m2), may be eligible to participate. Volunteers must be non-smoking, and have normal blood pressure. Volunteers must be willing and able to come to Ticon1 building at the UCD Medical Center in Sacramento and/or the research center (WHNRC) on the UC Davis campus for periodic lab visits over the course of 25 weeks.  There are also study visits at the Center for Neuroscience located in Davis (1544 Newton Court). At least 9 of the 33 visits must be held at the WHNRC (all test day visits). 

 

Who is NOT eligible to participate?

 

Women who

 

        • are outside the BMI range of 27 – 39.9 kg/m2,

 

        • have hypertension, or blood pressure above 140/90 mmHg

 

        • smoke or use tobacco products,

 

        • have signs of anemia, or low blood hemoglobin,

 

        • believe they have a sensitivity to MSG,

 

        • are pregnant, or are planning a pregnancy,

 

        • are vegetarians,

 

        • are taking medications for hypertension, depression, or weight loss,

 

        • are unable to undergo MRI testing due to internal    metal, wearing braces, or feeling claustrophobic.

 

What do I need to do to participate?

The study will take 26 weeks. You would first complete a health screening at the WHNRC on the UC Davis campus. The first appointment would last about 120 minutes, and would occur in the morning after an overnight fast. We will measure your height, weight, waist and hip circumference, blood pressure, temperature, heart rate. You will be asked about your usual menstrual cycle (periods). A blood sample will be taken to assess your general health. If the results of your screening meet the criteria of the study, you will be enrolled.

 

During the enrollment week (week 1), you will return to the WHNRC after an overnight fast for a visit that will take about 4 hours. As part of this visit, we will perform a Resting Metabolic Rate (RMR) measurement, by having you recline on a bed or chair after fitting you with an air collection mask. We will perform a DEXA scan of your whole body to determine your body composition (fat mass and fat-free mass). DEXA is a way of looking inside the body by using a very small amount of radiation. Because you are exposed to radiation, you will be required to take a pregnancy test. Pregnant women will not be allowed to continue in the study. Also, we will perform some cognitive tests, or simple computer tasks that simulate real-life decision making and an abbreviated intelligence test.

 

After enrollment, you will enter into a nine-week weight reduction phase (weeks 1-10), including weekly visits to the WHNRC to be weighed and to meet with a Nutrition Educator who will help you meet your weight loss goal (60 minutes each visit). Your calorie intake will probably be reduced by 500-750 kcal/day to reach this goal, depending on your height and weight. You will be asked to take a multivitamin each day to ensure adequate micronutrient intake during weight reduction. You will receive a diet log book and be asked to use it every day. The nutrition educator may also phone or email you twice a week. During weeks 4 & 7 we will measure RMR; these visits will take about one hour. At home, you will also wear a physical activity monitor called an Actical, a lightweight, watch like device that is worn around the waist and measures your body movements, energy expenditure, and heart rate (HR). It is waterproof but should be removed for swimming and bathing. You will wear it three times during the weight loss phase. If you are unable to meet your weight loss goal, you may be required to leave the study. You will receive payment for the part of the study you have completed (see “What is your compensation from this study?”).

 

At week 10, after you have lost 5 to 6 percent of your starting body weight, you will be asked to consume a controlled diet and you will be given all of the foods you need for the week.  All meals will be prepared, pre-portioned, and dispensed by the dietary staff of the WHNRC metabolic kitchen.  In addition, you will come into the WHNRC to be weighed twice during this week.

 

Upon completion of your maintenance feeding week, you will have two weeks of testing (weeks 11 and 12). During these weeks, you will continue to receive a maintenance diet with energy intake set to maintain current body weight. All foods will be prepared, pre-portioned, and dispensed by the dietary staff of the WHNRC metabolic kitchen. As part of this diet, you will receive powdered broth packets that you will need to prepare and consume three times a day, immediately before each meal. The broth will be made from ingredients that are commonly used in food products and when prepared with water, each will be 7 ounces (200 ml).

 

During week 11, baseline measurements will be made on 3 days using the following tests. You will receive and eat your breakfast and lunch at the testing facility on each of these days.

 

        On Day 1, you will have a functional Magnetic Resonance Imaging (fMRI) test. For the fMRI test, you will lie down on a narrow bed which will then move slowly into a tunnel that is 6 feet long by 22 inches wide and open at each end. You will need to lie there quietly for about one hour, during which time there will be a loud banging noise. During this time, you will be shown a series of photographs on a screen in which you will recognize common, everyday objects. While viewing the photographs, you will be asked to hold an electronic device in one hand, which has a buttons for responses. You will be asked to press the button every time you are shown a photograph with the appropriate rating (rating instruction explained prior to task). The MRI machine will collect data about your brain’s response to the photographs. This test day will take 7 hours.

        On Day 2, you will be asked to arrive at the WHNRC after fasting overnight for a blood draw by venipuncture. You will be provided breakfast, and continue testing. Just prior to lunch, a catheter (small plastic tube) will be inserted into your arm each for the collection of 10 blood samples taken at specific times. You will be asked to indicate your hunger and appetite at various times of the day using a hand-held (Palm) computer. Using a computer, you will be shown pictures of several different types of foods one at a time, and you will be asked how much you like that food. We will perform some cognitive tests, or simple computer tasks that simulate real-life decision making. You will be asked to participate in a challenging task for a total of about 25 minutes, so we can examine your body’s response to these tasks. These tasks will involve speech and subtraction problems. You will be asked to collect 10 saliva samples at specific times during the lab visits. This test day will take 8 hours.

        On Day 3, your resting metabolic rate (RMR) will be measured by having you recline on a bed or chair after fitting you with an air collection mask. This test will be done 3 times for 20 minutes each time. You will wear an activity monitor called an Actical and have another DEXA scan. This test day will take 5 hours.

During week 12, measurements will be made on 3 days using the same tests as week 11. You will receive and eat your breakfast and lunch at the testing facility on each of these days. You will also receive either a broth with monosodium glutamate (MSG) or with salt (sodium chloride).

 

        Day 1 – This is the same as week 11. This test day will take 7 hours.

        Day 2 - you will be asked to arrive at the WHNRC after fasting overnight for a blood draw by venipuncture. You will be provided breakfast, and continue testing. Just prior to lunch, a catheter (small plastic tube) will be inserted into your arm each for the collection of 10 blood samples taken at specific times. You will be asked to indicate your hunger and appetite at various times of the day using a hand-held (Palm) computer. Using a computer, you will be shown pictures of several different types of foods one at a time, and you will be asked how much you like that food. We will perform some cognitive tests, or simple computer tasks that simulate real-life decision making. You will be asked to participate in a rest period for 25 minutes. You will be asked to collect 10 saliva samples at specific times during the lab visits. This test day will take 8 hours.

        Day 3 - This is the same as week 11. This test day will take 5 hours.

         

During weeks 13-24, you will receive packets containing powdered broth that you will need to prepare and consume three times a day. You will receive broth powder with monosodium glutamate (MSG) or with salt (sodium chloride). This broth is made of commercially available ingredients and the MSG and salt levels will be similar to levels found in commercially available broths. You will prepare and drink approximately 7 ounces (200 ml) of this broth immediately before (within 5 minutes) each meal.

 

You will report weekly to the WHNRC to pick up your broth packets for the week. During this phase, you will be provided with “Guidelines for Healthy Eating” based on the instructional materials found at MyPyramid.com. Additional measurements will be taken during this phase, including six unannounced 24-h dietary recalls using the internet. You will come to the WHNRC for measurement of weight and RMR during weeks 15, 18, 21, and 24, each visit will take about 1 hour. During these weeks, you will wear an Actical at home.

 

At week 24 you will again be asked to consume a controlled diet and you will be given all of the foods you need for the week.  All meals will be prepared, pre-portioned, and dispensed by the dietary staff of the WHNRC metabolic kitchen.  In addition, you will come into the WHNRC to be weighed twice during this week.

 

During week 25, you will receive a study diet with energy intake set to maintain current body weight. All foods will be prepared, pre-portioned, and dispensed by the dietary staff of the WHNRC metabolic kitchen. Measurements will be made on 4 days using the following tests. You will receive and eat your breakfast and lunch at the testing facility on each of these days.

 

•   On Day 1, you will have a functional Magnetic Resonance Imaging (fMRI) test. This test day will take 7 hours.

•   On Day 2, you will undergo testing similar to Day 2, week 11. This test day will take 8 hours.

•   On Day 3, you will undergo testing similar to Day 3, week 11. This test day will take 5 hours.

 

What is your compensation from this study?

You will receive all testing at no cost to you. You will be paid for each portion of the study that you complete. You will receive $30 for the screening visit, $150 for reaching the first two test weeks, $50 for each laboratory visit week (week 11, 12 & 25), $50 for each fMRI visit and $100 for completing the study. If you complete the entire study, you will receive a total of $580. You will be paid by check, which will be mailed to you 2-3 weeks after completion of each test. If you do not complete all of the visits you will be compensated according to the scheme outlined above.

 

What should I do if I have questions?

Call (530) 754-7781, Press #1

 


Last Modified: 11/30/2012