Why eating in America may be less healthy than in Mexico

Another angle on obesity.  I just got back from interviewing Marian Neuhouser, a nutritional scientist at the Fred Hutchinson center.  She’s launching a new study of Mexican-American women.  She says more than 76% of Hispanic women in the U.S. are overweight or obese (the overall rate for women in the U.S. is 64%).  The experience of Mexican immigrants is similar to Japanese immigrants – within one generation in this country, the rates of obesity skyrocket.  That’s why many scientists say there’s something about living in modern America that is “obesogenic” – causing people to become obese.  The most likely and most important factor: diet.

Neuhouser’s hypothesis is that the switch in diet is a trigger, going from typical rural Mexican meals dominated by beans, rice and fresh-made tortillas, to a more American diet that’s full of processed foods, white flour, fatty meats, and sugary drinks.  But, she also suspects the problem for Mexican immigrants is exacerbated by their genetic profile and how it reacts to the American foods.

She just received funding to study this in detail, by getting 50 Seattle-area Mexican women to eat their meals at the Hutch for a month, so she can control their diet, while monitoring their blood for a number of biomarkers.

The biomarkers might also help explain why Hispanic women tend to get a more virulent, hard-to-treat form of breast cancer.

To mammogram, or not to mammogram

I’m not surprised there’s so much confusion about the new mammogram recommendations from the U.S. Preventive  Services Task Force.  The findings are counter-intuitive.  And the message is coming from data people, who can’t communicate it in a way that makes sense.

What’s more: There are a lot of people with a vested interest in the current mammogram regime.  I don’t mean to impugn their motives.  They have the best of intentions.  But, if your medical career, or your clinic, is built on the premise that all testing is good and early diagnosis is the Holy Grail, then it’s hard to be objective.  And, if you are affiliated with a non-profit advocacy group, trying to raise awareness and money to battle breast cancer, then it’s going to be hard to swallow the idea that not everyone needs to be tested.

A young woman lines up for her mammogram (at Baylor Medical Center)

This is intuitive:  Cancer starts small, and if you test for it, you might find it before it spreads and becomes lethal. If everyone gets tested, we’ll catch most cancers before they can kill.  Period.

This is not intuitive:  If we test people, and get a lot of false-positives, that causes anxiety and unnecessary biopsies.  So, it’s better to do less testing and risk a few deaths.

I’m not a specialist, and I won’t make any claims to know what all women should do.  But, the panel making the new recommendation deserves to be respected.  And their conclusion is not unprecedented.  Other researchers have been arguing for years that we do too much breast and prostate cancer screening.  European countries with the most advanced health systems do not recommend annual mammograms under the age of 50.

And as I talk to middle-aged women, I hear a lot of stories of false positives, or hard-to-read mammograms, and unhappiness with what feels like a treadmill of testing and worry. (Not to mention the mammogram procedure itself ….)

Back in the 1990’s, as CT scanning machines became more common (and less expensive),  “full body scans” became the rage.  Remember the ads?  They promised to find the diseases lurking in your body that hadn’t yet shown up in symptoms.  The medical profession roundly condemned these scans.  Why?  Because they lead to a lot of false positives, further useless testing, and possibly procedures that are unnecessary.  In the end, for most people, they do more harm then good.

If the government or medical profession is recommending that everyone should get a certain test or vaccine, then they need good evidence that the benefit outweighs the risks.

One fact we don’t like to think about:  We are all carrying around parasites and growths and abnormalities all the time.  Most of these are kept in check by natural systems.  If we tried to intervene on all of them, we’d create chaos in our bodies.

I imagine as this story evolves, we’ll see two sets of recommendations emerge–one for women with a family history of cancer (or other higher-risk status), and one for everyone else.