Nature volume 569, pages260–264 (2019) : Full Text: Rising rural body-mass index is the main driver of the global obesity epidemic in adults
- Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017.
- We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017—and more than 80% in some low- and middle-income regions—was due to increases in BMI in rural areas.
- In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women.
According to a recent study (EL Yu et al. J Pediatr 2019; 207: 64-70), about one-third of boys and one-fourth of girls with obesity have nonalcoholic fatty liver disease (NAFLD).
This study from San Diego with 408 children aged 9-17 years (mean 13.2 years) with obesity evaluated for NAFLD with laboratories (to exclude other etiologies) and with liver MRI proton density fat fraction (PDFF), with ≥5% considered the threshold for NAFLD.
- Prevalence of NAFLD was 26% in this population, with 29.4% in males and 22.6% in females
- The optimal cut offs of ALT for detecting NAFLD in this study were ≥30 U/L for females and ≥42 U/L for males. These are much lower than NASPGHAN guidelines which proposed ≥80 U/L or twice the ULN as thresholds for further investigation. (The NASPGHAN recommendations are likely to have higher specificity in identifying children at greater risk for nonalcoholic steatohepatitis (NASH).)
- 77% of this cohort were hispanic, thus prevalence may vary significantly in other populations.
- MRI-PDFF -the exact cut off is unclear. The authors note that if 3.5% were chosen, the NAFLD prevalence jumped to 49.3% (according to Table II –though the discussion stated 53.2%)
My take: Understanding the likelihood of NAFLD in children at risk is a helpful first step. This study points to the growing use of non-invasive diagnosis with MRI.
On a related topic, briefly noted: “Obesity in Adolescents and Youth: The Case for and against Bariatric Surgery” (A Khattab, MA Sperling. J Pediatr 2019; 207: 18-22). In this review, the authors refer frequently to endocrine society guidelines (J Clin Endocrinol Metab 2017; 102: 709-57). These guidelines generally recommend bariatric surgery only under specific conditions (eg. completion of Tanner 4 or 5 along with a BMI of 40 kg/m-squared or BMI of 35 with significant extreme comorbidities after failure of lifestyle modifications & without untreated psychiatric illness). This review predicts increasing use of bariatric surgery in adolescents “as more data on long-term outcomes in larger cohorts become known.”
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Yesterday’s post highlighted a study which indicated that low quality diets result in signiificant mortality. The tweets below refer to a study which indicated that supplements generally do not help one achieve a good diet. For a diet to be effective, the nutrients need to be present in the diet.
Link: Home Blenderized Tube Feedings: A Practical Guide for Clinical Practice
This article provides a lot of useful advice for blenderized formulas, but is not a substitute for the help of a qualified dietician/nutritionist.
With ImproveCareNow, there have been efforts to minimize variation in care. As such, there have been suggestions to monitor labs like vitamin D, vitamin B12, and folate routinely. I have voiced concern that some of this testing is unnecessary. For vitamin B12, deficiency in pediatrics is rare; at risk populations include those with extensive small bowel resections, gastric resections or strict vegan diet.
A recent article (J Fritz et al. Inflamm Bowel Dis 2019; 25: 445-59) which is a systematic review of micronutrients in pediatric inflammatory bowel disease provides further support for the approach of less testing.
- A total of 39 studies were included in the final review (2903 subjects, 1115 controls)
- Iron deficiency and vitamin D deficiency are common in pediatric patients with IBD
- Vitamin B12 and folate deficiency are rare
- Zinc deficiency is uncommon but increased in patients with Crohn’s disease compared to healthy controls.
- The authors recommend routine (at least yearly) testing for iron, vitamin D and zinc and that there is “insufficient evidence to support routine screening for other micronutrient deficiencies.”
My take: Except in patients with surgical resections and in those with unusual diets (eg. vegan), routinely checking vitamin B12, folate and most other micronutrients is unnecessary & low value care.
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Disclaimer: These blog posts are for educational purposes only. Specific dosing of medications/diets (along with potential adverse effects) should be confirmed by prescribing physician/nutritionist. This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.
A recent commentary in the NY Times discusses the future of personalized diets. Along the way, the commentary notes how little we know about the best diet and how difficult nutrition research is to complete.
The A.I. Diet by Eric Topol who is the author of the forthcoming “Deep Medicine,” from which this essay is adapted
It turns out, despite decades of diet fads and government-issued food pyramids, we know surprisingly little about the science of nutrition. It is very hard to do high-quality randomized trials: They require people to adhere to a diet for years before there can be any assessment of significant health outcomes…
Meanwhile, the field has been undermined by the food industry, which tries to exert influence over the research it funds.
Now the central flaw in the whole premise is becoming clear: the idea that there is one optimal diet for all people…
Only recently, with the ability to analyze large data sets using artificial intelligence, have we learned how simplistic and naïve the assumption of a universal diet is. It is both biologically and physiologically implausible: It contradicts the remarkable heterogeneity of human metabolism, microbiome and environment, to name just a few of the dimensions that make each of us unique. A good diet, it turns out, has to be individualized.
My take: Dr. Topol makes some important observations and he is right that there is not a simple diet solution for everyone. Nevertheless, in the near future, personalized medicine is not coming to our dinner tables and we have to rely on what we know right now –don’t eat too much sugar, do eat more fruits and vegetables, and don’t eat too much.
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