position:professor of medicine

How the sugar industry has distorted health science for more than 50 years
▻http://www.vox.com/2016/9/12/12864442/jama-sugar-industry-distort-science

“[...] Is it really true that food companies deliberately set out to manipulate research in their favor? Yes, it is, and the practice continues.” Nestle has been documenting the instances where companies fund nutrition studies that overwhelmingly return favorable results to the industry sponsors.

“Our research emphasizes that industry-funded science needs to be heavily scrutinized, and not taken at face value,” said Kearns, the lead author on the JAMA paper. “There are so many ways a study can be manipulated — from the questions that are asked, from how the information is analyzed, even to how the conclusions are described in the paper.”

In this case, the sugar industry involvement in science influenced not only the scientific enterprise but also public-health policy, and potentially, the health of millions of people. Kearns points out that the most recent World Health Organization sugar guidelines focus on reducing consumption because of sugar’s role in obesity and tooth decay — not the heart risk.

#sucre #santé

The Trouble With Scientists - Issue 24 : Error
▻http://nautil.us/issue/24/error/the-trouble-with-scientists

http://static.nautil.us/6069_55312eec654a75a08dc83de96adde735.jpg

Sometimes it seems surprising that science functions at all. In 2005, medical science was shaken by a paper with the provocative title “Why most published research findings are false.”1 Written by John Ioannidis, a professor of medicine at Stanford University, it didn’t actually show that any particular result was wrong. Instead, it showed that the statistics of reported positive findings was not consistent with how often one should expect to find them. As Ioannidis concluded more recently, “many published research findings are false or exaggerated, and an estimated 85 percent of research resources are wasted.”2 It’s likely that some researchers are consciously cherry-picking data to get their work published. And some of the problems surely lie with journal publication policies. But the (...)

Letter from Gaza, by Ellen Cantarow
▻http://mondediplo.com/blogs/letter-from-gaza

The email Mads Gilbert, professor of medicine at the University of North Norway (Tromso), sent to a friend on July 19 was a cri de coeur. He had spent two weeks in #Gaza during Israel’s Operation Cast Lead attack in the winter of 2008-09, tending to the wounded and the dying in Al-Shifa hospital, and again for another week during a similar assault (Operation Pillar of Cloud) in 2012.

As then, Gilbert is now once again caring for streams of patients rushed into Al-Shifa (the name means “healing”) from the Gaza killing fields. I reproduce the email in its entirety because it is the first lengthy account by a physician writing directly from a hospital about the region’s injured and dying in the course of Israel’s latest hostilities. Al-Shifa has been under bombardment and shellfire; other health care facilities as well as ambulances and medical personnel have been attacked. Gaza’s only rehabilitation hospital, Al-Wafa, has been destroyed.

Our Feel-Good War on Breast Cancer - NYTimes.com
▻http://www.nytimes.com/2013/04/28/magazine/our-feel-good-war-on-breast-cancer.html

In the United States, some researchers credit screening with a death-rate reduction of 15 percent — which holds steady even when screening is reduced to every other year. Gilbert Welch, a professor of medicine at the Dartmouth Institute for Health Policy and Clinical Practice and co-author of last November’s New England Journal of Medicine study of screening-induced overtreatment, estimates that only 3 to 13 percent of women whose cancer was detected by mammograms actually benefited from the test.

If Welch is right, the test helps between 4,000 and 18,000 women annually. Not an insignificant number, particularly if one of them is you, yet perhaps less than expected given the 138,000 whose cancer has been diagnosed each year through screening. Why didn’t early detection work for more of them? Mammograms, it turns out, are not so great at detecting the most lethal forms of disease — like triple negative — at a treatable phase. Aggressive tumors progress too quickly, often cropping up between mammograms. Even catching them “early,” while they are still small, can be too late: they have already metastasized. That may explain why there has been no decrease in the incidence of metastatic cancer since the introduction of screening.

At the other end of the spectrum, mammography readily finds tumors that could be equally treatable if found later by a woman or her doctor; it also finds those that are so slow-moving they might never metastasize. As improbable as it sounds, studies have suggested that about a quarter of screening-detected cancers might have gone away on their own. For an individual woman in her 50s, then, annual mammograms may catch breast cancer, but they reduce the risk of dying of the disease over the next 10 years by only .07 percent — from .53 percent to .46 percent. Reductions for women in their 40s are even smaller, from .35 percent to .3 percent.

If screening’s benefits have been overstated, its potential harms are little discussed. According to a survey of randomized clinical trials involving 600,000 women around the world, for every 2,000 women screened annually over 10 years, one life is prolonged but 10 healthy women are given diagnoses of breast cancer and unnecessarily treated, often with therapies that themselves have life-threatening side effects.

Study Points to New Culprit in Heart Disease - NYTimes.com
▻http://www.nytimes.com/2013/04/08/health/study-points-to-new-culprit-in-heart-disease.html?src=me

Chez les mangeurs de viande rouge les graisses saturées et le cholestérol ne contribueraient que de façon mineure au risque accru de maladie cardiaque, le vrai coupable étant un produit chimique qui est produit par des bactéries dans le tube digestif à partir de la carnitine de la viande (l’ingestion de pilules contenant de la carnitine a le même effet) puis est transformé par le foie en un autre produit chimique appelé TMAO qui pénètre dans le sang et augmente le risque de maladie cardiaque.

Ces bactéries, qui restent à découvrir, seraient en quantité bien moindre chez les végétariens et végétaliens.

...the investigators’ extensive experiments in both humans and animals, published Sunday in Nature Medicine, have persuaded scientists not connected with the study to seriously consider this new theory of why red meat eaten too often might be bad for people.

(...)

... the study’s findings indicated that the often-noticed association between red meat consumption and heart disease risk might be related to more than just the saturated fat and cholesterol in red meats like beef and pork.

Dr. Hazen began his research five years ago with a scientific fishing expedition. He directs a study of patients who come to the Cleveland Clinic for evaluations. Over the years, there have been 10,000. All were at risk for heart disease and agreed to provide blood samples and to be followed so the researchers would know if any patient had a heart attack or died of heart disease in the three years after the first visit. Those samples enabled him to look for small molecules in the blood to see whether any were associated with heart attacks or deaths.

That study and a series of additional experiments led to the discovery that a red meat substance no one had suspected — carnitine — seemed to be a culprit. Carnitine is found in red meat and gets its name from the Latin word carnis, the root of carnivore, Dr. Hazen said. It is also found in other foods, he noted, including fish and chicken and even dairy products, but in smaller amounts. Red meat, he said, is the major source, and for many people who eat a lot of red meat, it may be a concern.

The researchers found that carnitine was not dangerous by itself. Instead, the problem arose when it was metabolized by bacteria in the intestines and ended up as TMAO in the blood.

That led to [a] steak-eating study. It turned out that within a couple of hours of a regular meat-eater having a steak, TMAO levels in the blood soared.

But the outcome was quite different when a vegan ate a steak. Researchers had hypothesized that vegans would not have as many of the gut bacteria needed to make TMAO, and indeed virtually no TMAO appeared in the vegan’s blood after he consumed a steak.

“We did not expect to see such a dramatic difference,” Dr. Hazen said.

Then researchers gave meat eaters doses of antibiotics to wipe out almost all of their gut bacteria. After that, they no longer had TMAO in their blood either after consuming red meat or carnitine pills. That meant, he said, that the effect really was because of gut bacteria.

Researchers then tried to determine whether people with high blood carnitine or TMAO levels were at higher heart disease risk. They analyzed blood from more than 2,500 people, asking if carnitine or TMAO levels predicted heart attacks independently of traditional risk factors like smoking, high cholesterol and blood pressure. Both carnitine and TMAO did. But upon further analysis, they discovered that the effect was solely because of TMAO.

The researchers’ theory, based on their laboratory studies, is that TMAO enables cholesterol to get into artery walls and also prevents the body from excreting excess cholesterol.

But what is it about carnitine that bacteria like? The answer, Dr. Hazen said, is that bacteria use it as a fuel.

He said he worries about carnitine-containing energy drinks. Carnitine often is added to the drinks on the assumption that is will speed fat metabolism and increase a person’s energy level, Dr. Hazen said.

Dr. Robert H. Eckel, a professor of medicine at the University of Colorado and a past president of the American Heart Association, worried about how carnitine might be affecting body builders and athletes who often take it because they believe it builds muscle.

Those supplements, Dr. Hazen said, “are scary, especially for our kids.”