Letters
3. US Department of Health and Human Services. Protection of Human Subjects: criteria for IRB approval of research, §46.111 (a)(5) and (b). http://www .hhs.gov/ohrp/humansubjects/guidance/45cfr46.html#46.117. Accessed September 2, 2014.
In Reply Dr Carmack’s claim is at odds with results of numerous observational studies, meta-analyses, and 3 randomized controlled trials of medical male circumcision in Kenya, South Africa, and Uganda.1-3 The trials found relative risk ratios of HIV infection that were between 0.40 and 0.49 at 18 to 24 months following circumcision, or a reduction in the risk of HIV acquisition by 50% to 60%. In drawing attention to the absolute risk reduction due to circumcision in one of the trials, from 2.1 to 0.85 infections per 100 person-years, Carmack fails to recognize that the relative risk reduction is more relevant for understanding the potential effects of scaling-up male circumcision on the number of new HIV infections. Although our study objective was not to establish the HIV prevention effect of male circumcision, but instead to test an economic intervention that promoted circumcision uptake, we were motivated by the strong scientific evidence and by ongoing efforts in 14 African countries to scale up VMMC services. Male circumcision is a promising and cost-effective4 HIV prevention intervention in high-prevalence countries, and as indicated in the most recent global report5 from the Joint United Nations Programme on HIV/AIDS, there has been accelerating momentum in the scale-up since 2012. Kenya’s experience since launching VMMC in 2007, after consultations with stakeholders and support from the Luo Council of Elders, demonstrates the acceptability of medical male circumcision; more than 500 000 have been performed. Kenya’s experience also reinforces the HIV prevention benefit of male circumcision because nationally representative data from the recent Kenya AIDS Indicator Survey show that uncircumcised men remain significantly more likely to be infected with HIV.6 In many countries, the priorities are to identify novel demand-creation strategies for VMMC, provide highquality services, and deliver services in a low-cost, efficient manner that maximizes limited resources. Regarding Carmack’s concern that participants may have been given inaccurate information about the effects of male circumcision, we note that our study received approval from multiple ethics committees and all participants provided informed consent, in which the risks and benefits of medical male circumcision were clearly communicated. The study used information from the VMMC Communication Toolkit, which was developed by the Ministry of Health in Kenya and is widely used in the Nyanza region. The materials explain the circumcision procedure, state that “a circumcised man is up to 60% less likely to get infected with HIV,” and reinforce other ways to protect oneself from HIV. Moreover, participants who did seek circumcision at health facilities received additional counseling and information prior to undergoing the procedure, as per the standard of care in Kenya. In fact, the majority of people in Kenya are already aware of the HIV prevention benefit of male circumcision; the Kenya AIDS Indicator Survey indicates that 72% of HIVuninfected uncircumcised men know that circumcision provides partial protection from HIV. jama.com
In addition, the 3 trials, Kenyan survey data, and implementation science studies conducted in multiple countries in the past 5 years have consistently shown no increase in risky behaviors following circumcision outside clinical trial settings where counseling is less intense. Harsha Thirumurthy, PhD Kawango Agot, PhD Author Affiliations: Department of Health Policy and Management, Gillings School of Global Public Health, University of North Carolina, Chapel Hill (Thirumurthy); Impact Research and Development Organization, Kisumu, Kenya (Agot). Corresponding Author: Harsha Thirumurthy, PhD, Department of Health Policy and Management, Gillings School of Global Public Health, University of North Carolina, 135 Dauer Dr, Chapel Hill, NC 27599 ([email protected]). Conflict of Interest Disclosures: The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported. 1. Auvert B, Taljaard D, Lagarde E, Sobngwi-Tambekou J, Sitta R, Puren A. Randomized, controlled intervention trial of male circumcision for reduction of HIV infection risk: the ANRS 1265 Trial. PLoS Med. 2005;2(11):e298. 2. Gray RH, Kigozi G, Serwadda D, et al. Male circumcision for HIV prevention in men in Rakai, Uganda: a randomised trial. Lancet. 2007;369(9562):657-666. 3. Bailey RC, Moses S, Parker CB, et al. Male circumcision for HIV prevention in young men in Kisumu, Kenya: a randomised controlled trial. Lancet. 2007;369 (9562):643-656. 4. Sgaier SK, Reed JB, Thomas A, Njeuhmeli E. Achieving the HIV prevention impact of voluntary medical male circumcision: lessons and challenges for managing programs. PLoS Med. 2014;11(5):e1001641. 5. Joint United Nations Programme on HIV/AIDS (UNAIDS). Global Report: UNAIDS Report on the Global AIDS Epidemic 2013. Geneva, Switzerland: UNAIDS; 2013. 6. Kimanga DO, Ogola S, Umuro M, et al; KAIS Study Group. Prevalence and incidence of HIV infection, trends, and risk factors among persons aged 15-64 years in Kenya: results from a nationally representative study. J Acquir Immune Defic Syndr. 2014;66(suppl 1):S13-S26.
Energy Intake and Weight Loss To the Editor In a recent JAMA Patient Page, Dr Guth1 stated that “A total of 3500 calories equals 1 pound of body weight.” However, the energy content of body weight varies widely by race, sex, and age. The calorie density value of 3500 is based on the composition of adipose tissue. However, humans are rarely more than half adipose tissue; most of the remainder is skeletal muscle and bone, which have much lower calorie densities. Guth further stated, “This means if you decrease (or increase) your intake by 500 calories daily, you will lose (or gain) 1 pound per week. (500 calories per day × 7 days = 3500 calories.)” However, over time the calorie deficit slowly closes as energy expenditure gradually declines with the loss of body mass and metabolic adaptations. Unlike the linear weight loss pattern described by Guth, actual weight loss follows a smooth curve and then plateaus at the new energy requirement level. Although the calculations describing these weight loss curves are complex, validated web-based dynamic energy balance models are available.2,3 For example, if a 5′6″, 30-year-old woman weighing 180 lb and consuming 2622 calories daily reduced her intake by 500 calories per day, the 3500-calorie rule would estimate her weight loss at 1 year to be almost 52 lb. The validated dynamic model4 predicts a weight loss of 12 lb. At 10 years, the 3500JAMA December 24/31, 2014 Volume 312, Number 24
Copyright 2014 American Medical Association. All rights reserved.
Downloaded From: http://jama.jamanetwork.com/ by a University of St. Andrews Library User on 05/20/2015
2687
Letters
calorie rule would yield a negative body weight, whereas the weight loss prediction of the dynamic model would stabilize at a 31-lb loss after 3 years. Such inaccuracies can lead to erroneous judgments regarding the effects of clinical and public health measures. A more accurate public message would be to suggest that both health care workers and the public use either of the 2 freely available web-based applications to create realistic weight loss expectations as a function of energy intake or expenditure changes.2,4 David B. Allison, PhD Diana M. Thomas, PhD Steven B. Heymsfield, MD Author Affiliations: Nutrition Obesity Research Center, University of Alabama, Birmingham (Allison); Center for Quantitative Obesity Research, Montclair State University, Montclair, New Jersey (Thomas); Pennington Biomedical Research Center, Baton Rouge, Louisiana (Heymsfield). Corresponding Author: David B. Allison, PhD, Department of Biostatistics, University of Alabama, 1665 University Blvd, Birmingham, AL 35294 (dallison @uab.edu). Conflict of Interest Disclosures: The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Drs Allison and Thomas reported receiving grant support from the National Institutes of Health for teaching applications of mathematical sciences to obesity research. Dr Allison also reported receiving personal fees from Kellogg Company and Weight Watchers; collaborating on a project funded by the nonprofit International Life Sciences Foundation to predict weight changes in response to changes in energy balance; receiving or will receive fees from the nonprofit Nutrition Science Initiative, the Federal Trade Commission, Sage Publications, and Eisai; and receiving institutional grants, contracts, or unrestricted gifts awarded to the University of Alabama from Medifast and Cooking Light magazine. Dr Thomas also reported receiving funds from Jenny Craig. Dr Heymsfield reported serving on an advisory board for Medifast. 1. Guth E. Healthy weight loss [JAMA Patient Page]. JAMA. 2014;312(9):974. 2. Hall KD, Sacks G, Chandramohan D, et al. Quantification of the effect of energy imbalance on bodyweight. Lancet. 2011;378(9793):826-837. 3. Thomas DM, Martin CK, Lettieri S, et al. Can a weight loss of one pound a week be achieved with a 3500-kcal deficit? commentary on a commonly accepted rule. Int J Obes (Lond). 2013;37(12):1611-1613. 4. Bredlau C, Lettieri S; Pennington Biomedical Research Center. Weight Loss Predictor [web-based application]. http://www.pbrc.edu/research-and-faculty /calculators/weight-loss-predictor/. Accessed September 5, 2014.
In Reply Although the points raised by Dr Allison and colleagues have merit (weight loss in the long-term is more varied than the simple formula presented), the goal of the Patient Page is to provide easily understood information and accessible guidelines for the majority of patients. The second section, “What You Can Do To Lose Weight,” discussed assessing and adjusting diet and caloric intake based on actual results, without the use of a calculator. Considering that in actual practice many patients regain weight after they initially lose it, it is unlikely that an individual would continue to restrict calories for 10 years, ultimately resulting in a negative weight. Calculators are useful tools, but in the average, busy, primary care practice, most clinicians provide little weight loss guidance beyond “stop eating so much.” Educating clinicians about new tools available to them is important and useful, but I suspect the vast majority instead are seeking a simple option that requires minimal effort on their part. Incorporating the arteriosclerotic cardiovascular disease risk calculator into 2688
my daily practice has been sufficiently time consuming that I am reluctant to expect others to add yet another calculator into their daily routine. The practical reality of counseling patients is that there is very little time and little (if any) reimbursement for weight loss services. Goals are short-term and are adjusted based on a patient’s achieved weight loss and ability to make dietary adjustments. Patients adjust their diets based on what they can do to manage their eating habits and not on a rigid numeric calorie goal target. The art of weight loss counseling is to help the patient understand what aspects of the diet the patient can control. Often this has little to do with the number of calories in foods and focuses instead on changes based on a patient’s food preferences. The simple calculation in the article, whether accurate from a research perspective, provides sufficient information for a patient to understand the relationship between caloric content of foods and body weight to help them prioritize food preferences as they attempt to change their dietary habits with the goal of losing weight. Eve S. Guth, MD Author Affiliation: Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois. Corresponding Author: Eve S. Guth, MD, Jesse Brown Veterans Affairs Medical Center, 820 S Damen Ave, Chicago, IL 60612 ([email protected]). Conflict of Interest Disclosures: The author has completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported.
Calorie Labeling on Menus and Menu Boards To the Editor The Viewpoint by Drs Block and Roberto1 on calorie labeling on menus and menu boards summarized the possible benefits of this health promotion policy. We would like to emphasize the importance of expanding current evaluations to understand the effect of calorie labeling across socioeconomic backgrounds. For many high-income countries, the prevalence of excess weight follows a socioeconomic gradient, such that those with lower socioeconomic position, who often have lower levels of education, income, general and health literacy, and live in more disadvantaged neighborhoods, are disproportionately represented. Many factors are known to contribute to these inequalities. Policies that focus primarily on provision of information have been generally shown to be more effective for individuals with relatively greater social and economic resources.2 For example, considerable evidence from the tobacco-control literature has shown that media campaigns to promote smoking cessation in isolation are often less effective among more socioeconomically disadvantaged individuals compared with their more advantaged counterparts.3 Few studies have examined the effect of the provision of calorie information via labels by socioeconomic position. Of the few studies that have done so, and find calorie labeling to be effective, a greater benefit for those with higher socioeconomic position has been reported.4,5 Even though these studies have many limitations, and others report contrasting results, they highlight the need to understand the effect of calorie labeling across different socioeconomic groups.
JAMA December 24/31, 2014 Volume 312, Number 24
Copyright 2014 American Medical Association. All rights reserved.
Downloaded From: http://jama.jamanetwork.com/ by a University of St. Andrews Library User on 05/20/2015
jama.com
3. US Department of Health and Human Services. Protection of Human Subjects: criteria for IRB approval of research, §46.111 (a)(5) and (b). http://www .hhs.gov/ohrp/humansubjects/guidance/45cfr46.html#46.117. Accessed September 2, 2014.
In Reply Dr Carmack’s claim is at odds with results of numerous observational studies, meta-analyses, and 3 randomized controlled trials of medical male circumcision in Kenya, South Africa, and Uganda.1-3 The trials found relative risk ratios of HIV infection that were between 0.40 and 0.49 at 18 to 24 months following circumcision, or a reduction in the risk of HIV acquisition by 50% to 60%. In drawing attention to the absolute risk reduction due to circumcision in one of the trials, from 2.1 to 0.85 infections per 100 person-years, Carmack fails to recognize that the relative risk reduction is more relevant for understanding the potential effects of scaling-up male circumcision on the number of new HIV infections. Although our study objective was not to establish the HIV prevention effect of male circumcision, but instead to test an economic intervention that promoted circumcision uptake, we were motivated by the strong scientific evidence and by ongoing efforts in 14 African countries to scale up VMMC services. Male circumcision is a promising and cost-effective4 HIV prevention intervention in high-prevalence countries, and as indicated in the most recent global report5 from the Joint United Nations Programme on HIV/AIDS, there has been accelerating momentum in the scale-up since 2012. Kenya’s experience since launching VMMC in 2007, after consultations with stakeholders and support from the Luo Council of Elders, demonstrates the acceptability of medical male circumcision; more than 500 000 have been performed. Kenya’s experience also reinforces the HIV prevention benefit of male circumcision because nationally representative data from the recent Kenya AIDS Indicator Survey show that uncircumcised men remain significantly more likely to be infected with HIV.6 In many countries, the priorities are to identify novel demand-creation strategies for VMMC, provide highquality services, and deliver services in a low-cost, efficient manner that maximizes limited resources. Regarding Carmack’s concern that participants may have been given inaccurate information about the effects of male circumcision, we note that our study received approval from multiple ethics committees and all participants provided informed consent, in which the risks and benefits of medical male circumcision were clearly communicated. The study used information from the VMMC Communication Toolkit, which was developed by the Ministry of Health in Kenya and is widely used in the Nyanza region. The materials explain the circumcision procedure, state that “a circumcised man is up to 60% less likely to get infected with HIV,” and reinforce other ways to protect oneself from HIV. Moreover, participants who did seek circumcision at health facilities received additional counseling and information prior to undergoing the procedure, as per the standard of care in Kenya. In fact, the majority of people in Kenya are already aware of the HIV prevention benefit of male circumcision; the Kenya AIDS Indicator Survey indicates that 72% of HIVuninfected uncircumcised men know that circumcision provides partial protection from HIV. jama.com
In addition, the 3 trials, Kenyan survey data, and implementation science studies conducted in multiple countries in the past 5 years have consistently shown no increase in risky behaviors following circumcision outside clinical trial settings where counseling is less intense. Harsha Thirumurthy, PhD Kawango Agot, PhD Author Affiliations: Department of Health Policy and Management, Gillings School of Global Public Health, University of North Carolina, Chapel Hill (Thirumurthy); Impact Research and Development Organization, Kisumu, Kenya (Agot). Corresponding Author: Harsha Thirumurthy, PhD, Department of Health Policy and Management, Gillings School of Global Public Health, University of North Carolina, 135 Dauer Dr, Chapel Hill, NC 27599 ([email protected]). Conflict of Interest Disclosures: The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported. 1. Auvert B, Taljaard D, Lagarde E, Sobngwi-Tambekou J, Sitta R, Puren A. Randomized, controlled intervention trial of male circumcision for reduction of HIV infection risk: the ANRS 1265 Trial. PLoS Med. 2005;2(11):e298. 2. Gray RH, Kigozi G, Serwadda D, et al. Male circumcision for HIV prevention in men in Rakai, Uganda: a randomised trial. Lancet. 2007;369(9562):657-666. 3. Bailey RC, Moses S, Parker CB, et al. Male circumcision for HIV prevention in young men in Kisumu, Kenya: a randomised controlled trial. Lancet. 2007;369 (9562):643-656. 4. Sgaier SK, Reed JB, Thomas A, Njeuhmeli E. Achieving the HIV prevention impact of voluntary medical male circumcision: lessons and challenges for managing programs. PLoS Med. 2014;11(5):e1001641. 5. Joint United Nations Programme on HIV/AIDS (UNAIDS). Global Report: UNAIDS Report on the Global AIDS Epidemic 2013. Geneva, Switzerland: UNAIDS; 2013. 6. Kimanga DO, Ogola S, Umuro M, et al; KAIS Study Group. Prevalence and incidence of HIV infection, trends, and risk factors among persons aged 15-64 years in Kenya: results from a nationally representative study. J Acquir Immune Defic Syndr. 2014;66(suppl 1):S13-S26.
Energy Intake and Weight Loss To the Editor In a recent JAMA Patient Page, Dr Guth1 stated that “A total of 3500 calories equals 1 pound of body weight.” However, the energy content of body weight varies widely by race, sex, and age. The calorie density value of 3500 is based on the composition of adipose tissue. However, humans are rarely more than half adipose tissue; most of the remainder is skeletal muscle and bone, which have much lower calorie densities. Guth further stated, “This means if you decrease (or increase) your intake by 500 calories daily, you will lose (or gain) 1 pound per week. (500 calories per day × 7 days = 3500 calories.)” However, over time the calorie deficit slowly closes as energy expenditure gradually declines with the loss of body mass and metabolic adaptations. Unlike the linear weight loss pattern described by Guth, actual weight loss follows a smooth curve and then plateaus at the new energy requirement level. Although the calculations describing these weight loss curves are complex, validated web-based dynamic energy balance models are available.2,3 For example, if a 5′6″, 30-year-old woman weighing 180 lb and consuming 2622 calories daily reduced her intake by 500 calories per day, the 3500-calorie rule would estimate her weight loss at 1 year to be almost 52 lb. The validated dynamic model4 predicts a weight loss of 12 lb. At 10 years, the 3500JAMA December 24/31, 2014 Volume 312, Number 24
Copyright 2014 American Medical Association. All rights reserved.
Downloaded From: http://jama.jamanetwork.com/ by a University of St. Andrews Library User on 05/20/2015
2687
Letters
calorie rule would yield a negative body weight, whereas the weight loss prediction of the dynamic model would stabilize at a 31-lb loss after 3 years. Such inaccuracies can lead to erroneous judgments regarding the effects of clinical and public health measures. A more accurate public message would be to suggest that both health care workers and the public use either of the 2 freely available web-based applications to create realistic weight loss expectations as a function of energy intake or expenditure changes.2,4 David B. Allison, PhD Diana M. Thomas, PhD Steven B. Heymsfield, MD Author Affiliations: Nutrition Obesity Research Center, University of Alabama, Birmingham (Allison); Center for Quantitative Obesity Research, Montclair State University, Montclair, New Jersey (Thomas); Pennington Biomedical Research Center, Baton Rouge, Louisiana (Heymsfield). Corresponding Author: David B. Allison, PhD, Department of Biostatistics, University of Alabama, 1665 University Blvd, Birmingham, AL 35294 (dallison @uab.edu). Conflict of Interest Disclosures: The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Drs Allison and Thomas reported receiving grant support from the National Institutes of Health for teaching applications of mathematical sciences to obesity research. Dr Allison also reported receiving personal fees from Kellogg Company and Weight Watchers; collaborating on a project funded by the nonprofit International Life Sciences Foundation to predict weight changes in response to changes in energy balance; receiving or will receive fees from the nonprofit Nutrition Science Initiative, the Federal Trade Commission, Sage Publications, and Eisai; and receiving institutional grants, contracts, or unrestricted gifts awarded to the University of Alabama from Medifast and Cooking Light magazine. Dr Thomas also reported receiving funds from Jenny Craig. Dr Heymsfield reported serving on an advisory board for Medifast. 1. Guth E. Healthy weight loss [JAMA Patient Page]. JAMA. 2014;312(9):974. 2. Hall KD, Sacks G, Chandramohan D, et al. Quantification of the effect of energy imbalance on bodyweight. Lancet. 2011;378(9793):826-837. 3. Thomas DM, Martin CK, Lettieri S, et al. Can a weight loss of one pound a week be achieved with a 3500-kcal deficit? commentary on a commonly accepted rule. Int J Obes (Lond). 2013;37(12):1611-1613. 4. Bredlau C, Lettieri S; Pennington Biomedical Research Center. Weight Loss Predictor [web-based application]. http://www.pbrc.edu/research-and-faculty /calculators/weight-loss-predictor/. Accessed September 5, 2014.
In Reply Although the points raised by Dr Allison and colleagues have merit (weight loss in the long-term is more varied than the simple formula presented), the goal of the Patient Page is to provide easily understood information and accessible guidelines for the majority of patients. The second section, “What You Can Do To Lose Weight,” discussed assessing and adjusting diet and caloric intake based on actual results, without the use of a calculator. Considering that in actual practice many patients regain weight after they initially lose it, it is unlikely that an individual would continue to restrict calories for 10 years, ultimately resulting in a negative weight. Calculators are useful tools, but in the average, busy, primary care practice, most clinicians provide little weight loss guidance beyond “stop eating so much.” Educating clinicians about new tools available to them is important and useful, but I suspect the vast majority instead are seeking a simple option that requires minimal effort on their part. Incorporating the arteriosclerotic cardiovascular disease risk calculator into 2688
my daily practice has been sufficiently time consuming that I am reluctant to expect others to add yet another calculator into their daily routine. The practical reality of counseling patients is that there is very little time and little (if any) reimbursement for weight loss services. Goals are short-term and are adjusted based on a patient’s achieved weight loss and ability to make dietary adjustments. Patients adjust their diets based on what they can do to manage their eating habits and not on a rigid numeric calorie goal target. The art of weight loss counseling is to help the patient understand what aspects of the diet the patient can control. Often this has little to do with the number of calories in foods and focuses instead on changes based on a patient’s food preferences. The simple calculation in the article, whether accurate from a research perspective, provides sufficient information for a patient to understand the relationship between caloric content of foods and body weight to help them prioritize food preferences as they attempt to change their dietary habits with the goal of losing weight. Eve S. Guth, MD Author Affiliation: Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois. Corresponding Author: Eve S. Guth, MD, Jesse Brown Veterans Affairs Medical Center, 820 S Damen Ave, Chicago, IL 60612 ([email protected]). Conflict of Interest Disclosures: The author has completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported.
Calorie Labeling on Menus and Menu Boards To the Editor The Viewpoint by Drs Block and Roberto1 on calorie labeling on menus and menu boards summarized the possible benefits of this health promotion policy. We would like to emphasize the importance of expanding current evaluations to understand the effect of calorie labeling across socioeconomic backgrounds. For many high-income countries, the prevalence of excess weight follows a socioeconomic gradient, such that those with lower socioeconomic position, who often have lower levels of education, income, general and health literacy, and live in more disadvantaged neighborhoods, are disproportionately represented. Many factors are known to contribute to these inequalities. Policies that focus primarily on provision of information have been generally shown to be more effective for individuals with relatively greater social and economic resources.2 For example, considerable evidence from the tobacco-control literature has shown that media campaigns to promote smoking cessation in isolation are often less effective among more socioeconomically disadvantaged individuals compared with their more advantaged counterparts.3 Few studies have examined the effect of the provision of calorie information via labels by socioeconomic position. Of the few studies that have done so, and find calorie labeling to be effective, a greater benefit for those with higher socioeconomic position has been reported.4,5 Even though these studies have many limitations, and others report contrasting results, they highlight the need to understand the effect of calorie labeling across different socioeconomic groups.
JAMA December 24/31, 2014 Volume 312, Number 24
Copyright 2014 American Medical Association. All rights reserved.
Downloaded From: http://jama.jamanetwork.com/ by a University of St. Andrews Library User on 05/20/2015
jama.com
