From LA Times (reporting on CDC study): In U.S., 38% of adults and 17% of kids are now obese
“How do government agencies, private foundations, industry groups and professional societies squander hundreds of millions of dollars? By trying to fight America’s obesity epidemic.
Two new studies show that the best efforts of all these players – as well as schools, churches and individual healthcare providers – have largely failed to keep most Americans from getting fatter.”
A recent study (G Twig et al. NEJM 2016; 374: 2430-40) which had more than 42 million person-years of followup (1967-2010) showed that adolescents with a BMI in the 50th to 74th percentile (CDC values), well within the accepted normal range, had increased cardiovascular and all-cause mortality.
The study involved more than 2.3 million Israeli adolescents with up to 40 years of followup information. The study utilized data obtained from 17 year olds who were seen 1 year prior to mandatory military service. There was increasing mortality associated with higher BMI subgroups.
Key findings:
My take: this study shows that even modest increases in BMI are associated with modest increase in cardiovascular mortality over 40 years. Whether the BMI itself plays a causal role or is more of an epiphenomenon of other risk factors (eg. sedentary risk factors) is not clear.
A recent commentary (J Oberlander. NEJM 2016; 374: 1401-3) explains the “virtues and vices of single-payer health care.”
“In a country where nearly 30 million persons remain uninsured, even insured patients face staggering bills, and more money is spent on administration than on heart disease and cancer, it’s no surprise to hear calls for sweeping change.”
Virtues of Single-Payer System:
Vices of Single-Payer System:
It Does Not Matter if Single-Payer is Better:
It would face intense opposition from insurers, medical industry, and would not be adopted by Congress. “In short, single payer has no realistic path to enactment in the foreseeable future.”
My take (in agreement with author): “Preserving and strengthening the ACA [affordable care act] as well as Medicare, and addressing underinsurance and affordability of private coverage is a less utopian cause than single payer. I believe it’s also the best way forward now for U.S. medical care.”
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Graphic showing association between obesity and asthma
A thought-provoking editorial from the NY Times provides a lot of reasons why dieting to lose weight may be counter-productive. This editorial comes right after recent reports that many of the most successful “biggest losers” have regained their weight. Here’s the link. Never Diet Again
Key points:
Here a few excerpts:
Setpoint: “When dieters’ weight drops below it, they not only burn fewer calories but also produce more hunger-inducing hormones and find eating more rewarding.”
Diet industry: ” A report for members of the industry stated: “In 2002, 231 million Europeans attempted some form of diet. Of these only 1 percent will achieve permanent weight loss.”
Does dieting increase weight gain? “The causal relationship between diets and weight gain can also be tested by studying people with an external motivation to lose weight. Boxers and wrestlers who diet to qualify for their weight classes presumably have no particular genetic predisposition toward obesity. Yet a 2006 study found that elite athletes who competed for Finland in such weight-conscious sports were three times more likely to be obese by age 60 than their peers who competed in other sports.”
Obesity overrated as cause of mortality: “But our culture’s view of obesity as uniquely deadly is mistaken. Low fitness, smoking, high blood pressure, low income and loneliness are all better predictors of early death than obesity. Exercise is especially important: Data from a 2009 study showed that low fitness is responsible for 16 percent to 17 percent of deaths in the United States, while obesity accounts for only 2 percent to 3 percent, once fitness is factored out.”
My take: This short article explains quite well why obesity is so hard to treat with diet approaches. Primary prevention of obesity at younger ages along with emphasis on staying active are likely to achieve more than focusing on diet alone.
University of Michigan, Law Quad
A terrific review (ED Rosen. NEJM 2016; 374: 885-7) explains how cool temperature can alter the microbiome and the implications of this finding.
Background: mammals have at least two types of adipose tissue: “the familiar (and all too abundant) white fat that stores calories, and brown adipose tissue that dissipates energy…studies of mice have identified several drivers of the appearance of beige fat cells in white fat pads, a process known as ‘browning.'”
Reviewed study: Chevalier et al. Cell 2015; 163: 1360-74.
“This new work shows that cold exposure, like dietary change, provokes alterations in the gut microbiota of mice. Moreover, when cold-adapted flora are transferred to a germ-free animal, the recipient mouse loses fat mass and has improved insulin sensitivity…[they] are better able to defend their body temperature on being placed in the cold.”
My take: In totality, these studies demonstrate how multiple organs (in this case: adipose tissue and the gut) work together to face an environmental challenge. Furthermore, changes in the gut microbiome may be important for therapeutic advantage in many disease states including obesity, type 2 diabetes, short bowel syndrome, irritable bowel syndrome and many others. Now, that is cool.
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View from Walnut Street Bridge, Chattanooga
A recent study (C Grimes et al. 24-h urinary sodium excretion is associated with obesity in a cross-sectional sample of Australian schoolchildren British Journal of Nutrition Volume 115 / Issue 06 / March 2016, pp 1071 – 1079) was summarized at AJP.com.au: Childhood salt intake linked to obesity.
An excerpt:
The study also found that in both four-to-seven-year olds and eight-to-12-year-olds, the prevalence of abdominal obesity was also higher in children with a higher intake of salt.
The recent findings published in the British Journal of Nutrition came from the SONIC (Salt and Other Nutrient Intakes in Children) study that measured salt intake in 666 primary schoolchildren aged four to 12 years….
“We found that 70% of Australian children are eating over the maximum amount of salt recommended for good health.
“In this study children were eating on average six grams of salt a day, which is over a teaspoon, and they should be aiming to eat about 4-5 grams a day.
”For every additional gram of salt children ate this was associated with a 23% greater likelihood of being overweight or obese. Such high intakes of salt are setting children up for a lifetime risk of future chronic disease such as high blood pressure and heart disease”
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From NPR: Sleep Munchies: Why It’s Harder to Resist Snacks When We’re Tired
An excerpt:
There’s lots of evidence that getting too little sleep is associated with overeating and an increased body weight.
The question is, why? Part of the answer seems to be that skimping on sleep can disrupt our circadian rhythms. Lack of sleep can also alter hunger and satiety hormones.
Now, a new study finds evidence that sleep deprivation (getting less than five hours of sleep per night) produces higher peaks of a lipid in our bloodstream known as an endocannabinoid that may make eating more pleasurable.
So, what’s an endocannabinoid? If you look at the word closely, you may already have a clue. The prefix endo means inner, or within. And cannabinoid looks like … you got it: cannabis.
My take: Another good reason to avoid being on call -it could lead to sleep deprivation/weight gain.
Old San Juan
A provocative study from Brazil (CSE Halal et al. J Pediatr 2016; 168: 99-103) examined a cohort of 4231 infants and assessed sleep duration from 1-4 years of age.
Findings:
This study introduction notes that studies in adults have suggested an association between poor sleep and weight gain, “possibly through elevation of cortisol and gherlin levels, along with reduction in leptin levels, thereby leading to increased hunger and reduced energy expenditure.”
Normal sleep patterns: for infants 12-15 hours/day, & for toddlers 11-14 hours/day. At night, average expected sleep is 12 hours at 1 year of age and 11 hours at 4 years of age.
My take: Looking at early sleep patterns helps reduce the likelihood of reverse causation. This study and others shows an association with less sleep and increased likelihood of weight gain. Why???
In same issue (AI Wijtzes et al. J Pediatr 2016; 168: 118-25) report that breakfast skipping at age 4 years is associated (ß =1.38) with a higher percent fat mass at age 6 years, though no associations were found with BMI or weight status. This study involved prospectively collected data from 5914 children in the “Generation R Study” in The Netherlands.
Briefly noted: JA Emond et al. J Pediatr 2016; 168: 158-63. “Greater child commercial TV viewing was significantly associated with more frequent family visits to those fast food restaurants …toy collecting partially mediated that positive association.” This study involved 100 parents with children aged 3-7 in a rural community.
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This graphic identifies commercial entities influencing food choices
A prospective study (TH Inge et al. NEJM 2016; 374: 113-23) with 242 adolescents from five U.S. centers provides data on outcomes at 3 years. Here’s the scoop:
At 3 years:
Table 4 details the serious complications:
The most common nutrient deficiency at followup was iron deficiency. 57% had low ferritin levels at 3 years compared with 5% at baseline. Vitamin B12 deficiency was common; it declined by 35% and 8% had a deficiency at 3 years. Vitamin A deficiencies increased (16% at 3 years). My take: this study documents the durability of weight loss and its beneficial effects on a multitude of problems. It also shows that careful followup is needed for nutrient deficiencies and the risks of adverse events. Related blog posts:
A recent commentary from the NY Times (A Healthy Diet’s Main Ingredients? Best Guesses) explores some of the failed efforts to improve health by reducing fat or eliminating eggs and explains why these are no longer recommended. The article has a 12 minute video which reviews some of the confusion regarding dietary recommendations.
Here’s an excerpt:
Conventional wisdom held that fat was bad, period, with relatively few Americans distinguishing between saturated fats (meat, eggs, dairy products) and healthier unsaturated fats (fish, vegetable oils, nuts). Typically, people turned to breads, cereals and potatoes — and to sugary soft drinks — for the calories they no longer got from protein-rich foods…The result? Carbo-loading Americans grew fatter. “We put the whole country on a low-fat diet,” Mr. Taubes said, “and, lo and behold, we have an obesity epidemic.”…
New guidelines are expected to be issued this month by the Departments of Agriculture and of Health and Human Services, which tend to follow the recommendations of an advisory committee. One likely eye-catcher is a new assessment of cholesterol, long an archvillain. It seems destined for rehabilitation to some degree. Months ago, the advisory committee concluded that the dietary intake of cholesterol (the body produces this waxy, artery-obstructing matter on its own) had no real effect on blood levels of LDL, the so-called bad cholesterol. “Cholesterol,” the committee said, “is not a nutrient of concern for overconsumption.”
There is a conspicuous American tendency to cling to a favored diet as the gateway to good health, keeping weight down, staving off cancers and banishing heart attacks. A consequence is an abundance of regimens — vegan, gluten-free, Paleolithic, fruitarian and many more — each promoted by its adherents as the one true path.
But nutrition experts, including those in this Retro Report, caution that life is complex, and that we are more than what we eat.
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gutsandgrowth 