3
Tanita TBF-551 Body Fat Monitor/Scale
2
Safety precautions
Important notes for users
Principles of body fat percentage measurement
What is body fat percentage?
Reasonable ranges of body fat percentage
Body fat percentage measurement
Body fat percentage fluctuations in a day
Advantages of the Tanita Body Fat Monitor/Scale TBF-551
Features and functions of TBF-551
Components
Measuring platform
Accessories
Useful features of the TBF-551
Switching the Weight Mode (lb, kg or st-lb)
Preparations before use
Inserting the batteries
Positioning the unit
Attaching the support feet
How to measure body fat percentage
Overview of measuring
Setting and storing data in memory
Taking measurements
Taking weight measurement only
Changing values in memory
Replacing the batteries
Troubleshooting
Warranty form
Table of contents
1
2
4
5
6
7
9
10
FEDERAL COMMUNICATIONS COMMISSION NOTICE
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide rea-
sonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used
in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular
installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encour-
aged to try to correct the interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
• Consult the dealer or an experienced radio or television technician for help.
Modifications
The FCC requires the user to be notified that any changes or modifications made to this device that are not expressly approved by Tanita Corporation may void the user’s
authority to operate the equipment.
The Tanita Body Fat Monitor/Scale TBF-551 allows you to measure your body fat
percentage at home as easily as you measure your weight.
What is body fat percentage?
Body fat percentage is the percentage of fat in your body. Until now, your absolute
weight has determined whether or not you were considered overweight or obese. In
recent years, the definition of obesity has been refined to mean the presence of excess
body fat. Too much body fat has been linked to conditions such as high blood pressure,
heart disease, diabetes, cancer, and other disabling conditions.
The BIA method
The TBF-551 uses the BIA (Bioelectrical Impedance Analysis) technique. In this method,
a safe low-level electrical signal is passed through the body. It is difficult for the signal to
flow through fat in the human body, but easy to flow through moisture in the muscle
and other body tissues. The difficulty with which a signal flows through a substance is
called impedance. So the amount of fat in the body can be accurately estimated by mea-
suring the impedance. The signal used is very low, making it safe and imperceptible.
The illustration on the left show how the signal travels through the body.
Body fat percentage fluctuations in a day
Hydration levels in the body may affect body fat readings. Readings are usually highest
in the early waking hours, since the body tends to be dehydrated after a long night’s
sleep. For the most accurate reading, a person should take a body fat percentage reading
at a consistent time of day under consistent conditions.
Besides this basic cycle of fluctuations in the daily body fat readings, variations may be
caused by hydration changes in the body due to eating, drinking, menstruation, illness,
exercising, and bathing. Daily body fat readings are unique to each person, and depend
upon one’s lifestyle, job and activities.
The graph on the left shows an example of daily body fat percentage fluctuations.
Advantages of the Tanita TBF-551
Previously, body fat percentage was determined by measuring the thickness of subcuta-
neous fat by pinching it with calipers, or by laying a person on a scanning bed and pass-
ing a current from hand to foot. However, these methods had problems; measurement
values varied, professional skills were required, and extensive time was required for mea-
surement. Currently, the gold standard methods of fat percentage measurement are the
underwater weighing method and DEXA (dual energy x-ray absorbsiometry).
Based on data from DEXA, Tanita established a formula for estimating the body fat per-
centage. There is a high correlation between measurements taken with the TBF-551 and
those obtained through the underwater weighing and DEXA methods.
Principles of body fat percentage measurement
Based on NIH/WHO BMI Guidelines.
