We expect a bit better from the legendary “gray lady” of American journalism.
Many health-savvy readers of The New York Times were surprised to see the headline, “For Heart Risk, No Telltale Body Shape”, in the Science section of the paper’s March 16, 2011, edition (Rabin RC 2011).
In a “meta-analysis” summarized by Times reporter Roni Rabin, scientists based at Britain’s University of Cambridge analyzed data from 58 studies involving 221,934 people, and published their findings in Britain’s Lancet medical journal (ERFC 2011).
Surprisingly, they found no strong links between heart risk and either total body weight or body shape (waist circumference or waist-to-hip ratio).
The Times quoted study co-author Dr. Emanuele Di Angelantonio making the unjustifiably sweeping claim, “Whatever your shape is doesn’t really matter.”
New York Times report contradicted … quickly
Just two months after the Times article appeared, a study among almost 82,864 British heart patients affirmed prior findings tying belly fat to increased heart risk (Czernichow S et al. 2011).
Their analysis showed that having a higher waist circumference or waist-to-hip ratio raised the risk of dying from cardiovascular disease (CVD) by an average of 15 percent.
Worse yet, the risk of dying from CVD was 66 percent greater in the one-fifth of the participants with the biggest pot bellies in relation to their hip size (i.e., the highest waist-to-hip ratio).
As they wrote, “… measures of abdominal adiposity [central obesity], but not BMI [body mass index], were related to an increased risk of CVD mortality [cardiovascular death).” (Czernichow S et al. 2011)
And, in the very same month the Cambridge meta-analysis reported in The New York Times was published, a Mayo Clinic team published a contradictory study among 855 patients, which underscored the dangers of central obesity:
“Low fitness and central obesity were independently and cumulatively associated with increased mortality in coronary artery disease patients.” (Goel K et al. 2011)
Mayo Clinic team confirms belly-heart link, consistently
In another large study, published this month, the same Mayo Clinic team found that people who have heart disease and even a modest pot belly are at higher risk for death than people whose fat collects elsewhere (Coutinho T et al. 2011).
Importantly, this increased risk was seen even in patients with a normal Body Mass Index (BMI) … a combined measure of height and weight.
The Mayo team analyzed data from 15,923 people with coronary artery disease who were participating in five studies around the world.
They found that people with coronary artery disease and central obesity – as measured by waist circumference and waist-to-hip ratio – had up to twice the risk of dying.
That increased risk is equivalent to the risk of smoking a pack of cigarettes per day or (particularly for men) having very high cholesterol.
The findings add critical nuance to the so-called “obesity paradox” seen in many studies, in which heart patients with a high BMI have better survival odds than normal-weight individuals.
As Mayo lead author Thais Coutinho, M.D., said, “We suspected that the obesity paradox was happening because BMI is not a good measure of body fatness and gives no insight into the distribution of fat. BMI is just a measure of weight in proportion to height. What seems to be more important is how the fat is distributed on the body.” (MC 2011)
Lead Mayo investigator Francisco Lopez-Jimenez, M.D., explained why this type of fat may be more harmful:
“Visceral [abdominal] fat has been found to be more metabolically active. It produces more changes in cholesterol, blood pressure and blood sugar. However, people who have fat mostly in other locations in the body, specifically, the legs and buttocks, don't show this increased risk.” (MC 2011)
Dr. Lopez-Jimenez could have added that abdominal fat cells generate “cell-signaling” proteins (cytokines) that induce low-level inflammation … an effect that indirectly promotes obesity, heart disease, and diabetes (Hung J et al. 2008; Cartier A et al. 2009; Katsoulis K et al. 2009; Ackermann D et al. 2011).
In addition, belly fat reduces levels of adiponectin … a potent “anti-diabetic” hormone that also helps discourage weight gain and heart disease (Milewicz A et al. 2009).
Times report ignored reams of prior evidence tying pot bellies to heart risk
We can’t expect the Times to have predicted such a quick contradiction of the Cambridge meta-analysis.
But the paper’s coverage of that study failed to mention the large body of prior evidence linking so-called “central obesity” – commonly known as a pot belly or muffin top – to increased heart risk.
In fact, every major health organization agrees that central obesity is one of the key signs of metabolic syndrome, which predicts higher risk for heart disease and diabetes.
Just a month before the Cambridge meta-analysis was published, researchers at the Mayo Clinic published their review of the evidence, which concluded, “There is abundant data suggesting that measuring central obesity or total body fat content might be more appropriate [for gauging heart risk] than using the body mass index alone.” (López-Jiménez F et al. 2011)
The researchers say physicians should advise heart patients with normal BMIs to lose weight if they have a large waist circumference or a high waist-to-hip ratio.
The measure is very easy to use, Dr. Coutinho says: “All it takes is a tape measure and one minute of a physician's time to measure the perimeter of a patient's waist and hip.”
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Hung J, McQuillan BM, Thompson PL, Beilby JP. Circulating adiponectin levels associate with inflammatory markers, insulin resistance and metabolic syndrome independent of obesity. Int J Obes (Lond). 2008 May;32(5):772-9. Epub 2008 Feb 5.
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López-Jiménez F, Cortés-Bergoderi M. Update: systemic diseases and the cardiovascular system (i): obesity and the heart. Rev Esp Cardiol. 2011 Feb;64(2):140-9. English, Spanish.
Milewicz A, Jedrzejuk D, Dunajska K, Lwow F. Waist circumference and serum adiponectin levels in obese and non-obese postmenopausal women. Maturitas. 2010 Mar;65(3):272-5. Epub 2009 Dec 9
Rabin RC. Patterns: For Heart Risk, No Telltale Body Shape. March 16, 2011. Accessed at http://www.nytimes.com/2011/03/22/health/research/22patterns.html