Childhood obesity and overweight is becoming a major issue today. If you are facing this situation with your child, you have got to understand the notion of resting metabolic rate (RMR) and how it can help you manage your child’s weight.
I first learned about RMR from Milton Stokes, who is a registered dietitian and an expert in weight management issues. He told me that a test is now available for measuring RMR and it may even be covered by your health insurance. I was so intrigued by it that I asked him to connect me with an expert on the science behind RMR and this new measurement technique so I could share a detailed article with you. Check it out and let me know if you have any questions. I will post a follow up article to get your questions answered.
|Scott McDoniel, PhD
Scott McDoniel has a PhD in Psychology with a focus towards Health/Behavioral Medicine. In addition, Dr. McDoniel has a Masters of Education in Exercise Physiology. Professionally, Dr. McDoniel has over 15 years experience helping adults and children with living a healthier lifestyle and has counseled over 1,500 patients on weight management. Dr. McDoniel is also a clinical researcher and is focused on topics related obesity, energy metabolism, and healthcare delivery. He has a number of publications and presentations on these topics. He is currently employed as the Director of Clinical Affairs for Microlife Medical Home Solutions, Inc. and is a faculty member at Walden University’s School of Health Sciences.
Question: What is Resting Metabolic Rate (RMR) and how does it relate to weight gain?
Scott: Weight management is a simple, yet often difficult, task of balancing energy (i.e., calories) intake with expenditure. Individuals will gain weight when they consume more calories then what they typically burn. The opposite is true for weight loss; burn more calories then calories consumed. In order to determine appropriate energy balance an individual needs to know how many calories they burn each day. Total energy expenditure (TEE) is comprised of resting metabolic rate (RMR), activities of daily living, and the thermic effect of food (TEF). RMR is the main metabolic factor and represents between 60 to 75% of TEE while TEF is approximately 5-10% of TEE [1, 2]. Essentially, the higher the RMR higher is the TEE unless you are more active then the usual individual.
Question: How does this apply to young children?
Scott: Weight gain in children is a topic of great concern. The prevalence of overweight children is 15.5% for 12 to 19-year-olds, 15.3% 6 to 11 year-olds, and 10.4% among 2 to5 year-olds. Overweight has increased five percentage points among 12 through 19 year-olds from 10.5% to 15.5% in approximately 10 years . Unfortunately, future projections indicate children that become overweight as children are at substantial risk of becoming obese later in life.
The children in the U.S. lead a very sedentary lifestyle. With the advent of video games, decreased physical activity in schools, and other social pressures children are not burning a lot of calories throughout the day. In-comparison, studies have indicated that they are consuming large amounts of calories. Therefore, they are in a positive energy balance (i.e., consume more calories then what is being burned). It is not so much a question of a slow metabolism but more of an issue with lack of activity.
This being said, parents should consider having their child’s RMR and activity level measured to best determine TEE. This will help a clinician tailor a nutrition plan to meet the weight management needs of the child.
Question: What determines a child’s RMR? Is it genetic or are there environmental factors?
Scott: RMR is regulated by a complex biochemical and central nervous system. Recent advancements in the Human Genome Project have led to a better understanding of genetic influences in several disease and metabolic states. The mitochondrial uncoupling protein 2 (UCP2) gene has been linked to obesity by way of possible influence on RMR [4-6].
However, it is estimated that this specific genetic influence may only account for the about 5 % of the variance in RMR.
Other biochemical influences may be related to specific hormones (i.e., Testosterone, Leptin). Much is known about the role testosterone has on the human body by way of muscle tissue generation. However, new research has indicated Leptin influences energy metabolism as-well. Leptin is typically known for its regulation of appetite and hunger.
Individuals that are leptin-deficient are often obese and have a lower RMR then normal weight individuals .
Still to this day, fat-free body weight is the main contributing factor on RMR. Studies have routinely indicated fat-free bodyweight predicts 80% of an individual’s RMR. Therefore, having more muscle weight in-comparison to fat weight will result in a higher RMR.
Question: Is there a relationship between autism, asthma, food allergy or other health conditions and RMR?
Scott: RMR does change with various health conditions. Most of the time, when an individual is hospitalized for an acute illness their RMR increases. The main reason why RMR increases is the body is trying to repair itself. This is a common reason why individuals typically lose weight when they are in the hospital. In addition, medications for several psychological (depression, schizophrenia, etc.) and physiological diseases (hypertension, diabetes, etc.) have shown to slow RMR [8-11]. However, some medications may not alter RMR but have an effect on overall TEE.
A study conducted in 1999, indicated medications prescribed for children with attention-deficit/hyperactivity disorder had no effect on RMR. However, the medication did result in decreased physical activity by 16-20% .
Since there are many disease states and medications that can affect RMR it is important to monitor RMR during medical management of given condition. Since RMR usually changes with a 5-10% weight change it is recommended, that patients receive a RMR measurement so clinicians can prescribe the most accurate nutrition program to best manage bodyweight.
Question: Where can I get my child’s RMR measured?
Scott: Measuring RMR is still fairly new. However, technology has made measurement of RMR easier and more applicable to general wellness facilities and out-patient medical clinics. You can search for health and wellness professionals online at Microlife Medical Home Solutions . The cost for a metabolic test is approximately $50-75 depending on location. In addition, insurance companies may cover this measurement if your child is overweight and/or has an underlying medical issue that has caused abnormal weight gain.
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Disclaimer – Information provided in this article should not be considered as medical advice. Consult with your physician if you think your child needs an RMR test and how it can be used to control and/or reverse weight gain. I have no business relationship with Microlife Medical Home Solutions, Inc., and this article is not an endorsement of their products and services.