Salt: How bad is it?

Back in the 1990s, I took two courses that studied the effects of salt on health. Both courses questioned whether reducing salt intake would improve health. In my introductory nutrition course at Cornell, Dr. David Levitsky started to break down the evidence on salt. He showed that reducing salt only reduced blood pressure in some individuals (i.e. those that were salt sensitive). 

I took another course where we really dove into the evidence around salt. Dr. Charles McCormick showed us evidence that there was tremendous variation in salt's relationship with blood pressure. In addition, weight was an important determinant of blood pressure, that overshadowed the effects of salt. Finally the ratio of sodium to potassium was a stronger predictor of high blood pressure, than sodium alone. (Potassium is found in fruits and vegetables.)

A good review of the recent evidence doubting the connection between salt and cardiovascular mortality is here, by friend Dr. Sean Lucan. He states, "Attempting to Reduce Sodium Intake Might Do Harm and Distract From a Greater Enemy."

There have been many skeptics in the salt and high blood pressure connection. Now we finally have an ally: the prestigious Institute of Medicine. They issued a report today saying:

“These new studies support previous findings that reducing sodium from very high intake levels to moderate levels improves health,” said committee chair Brian Strom, George S. Pepper Professor of Public Health and Preventive Medicine at the University of Pennsylvania Perelman School of Medicine. “But they also suggest that lowering sodium intake too much may actually increase a person’s risk of some health problems.”

While salt may not be a primary cause of death, it is a marker of processed food. In our recent study, we found that adolescents ate a tremendous amount of sodium at Subway and McDonald's. It may not be that the salt itself is the harmful part of this diet. It simply may be that foods with high salt are are heavily processed food-like substances. Reducing the amount of salt in these heavily processed "foods", such as processed meat and snack foods, is unlikely to have a very positive effect on health. The real gains will happens if we can get people to eat less of these foods and more potassium containing foods: vegetables.

So enjoy your salt when you add a little to your food. But stay away from foods with a lot of salt on the label. They are likely foods that are shortening your life.

How to tell if a patient is eating well

Today I was invited to give a talk to medical students at UCSF.  The talk was about how to talk to patients about nutrition and behavior change.  I started with this question:

"How do you know if your patient is eating well?"

The first responses I received from the audience were:

"Test cholesterol."

"Test blood sugar."

"Weigh them."

"Waist circumference."

Finally, a brilliant student said, "Talk to them."

I had to reframe the question to: "How would you assess a patient's eating by only talking to them?"  We then had a good talk on objective methods to assess eating behaviors.

I was floored that most of the first answers to the question were, "order more tests."  The medical community has already taught these early medical students that a test is the answer to every question in medicine.  Is it any surprise that we order too many tests with minimal value?

On the positive side, we spent the rest of the hour talking about nutrition and behavior.  I was surprised how well the students knew about current concepts in nutrition.  I hope the next generation of physicians become engaged with their patients about nutrition.  I have faith they will, as long as the current system does not steer them in the wrong way.

Is Local Food the Answer?

In this fascinating post, the authors of Freakonomics talk about a study showing that eating local food may actually increase environmental and monetary costs.  Why?  Economists know that specialization reduces cost.  It actually make take less energy to grow something far away and transport it by boat to California, rather than just grow it here.

So local food may not be the answer to global warming.  But, was that the problem it was supposed to solve?

Growing and purchasing food locally has other advantages.  It makes food-born illness easier to track, as we know where the food is grown.  In an even larger sense, it promotes social cohesion and social interaction.

Many of the problems in our food system arise because we do not know where food comes from.  We do not know who grew it or how they grew it.  For instance, let's take eggs.  For those that eat animal products, would you eat an egg if you knew the hens lived in a crowded, dark shelter with feces covering the ground?  Or would you prefer to eat an egg that came from a farmer that you could ask how the animal lived, what it was fed, and how fresh the egg was?  Buying directly from a farmer does not require a food label; it just relies on talking.

We have created a society that is not in touch with real food.  We don't know what food is.  We think a Big Mac is food.  Buying locally restores our connection to where our food comes from.  We have to weigh those benefits with the possible negative consequences of local food.

We don't need to eat all our food locally.  We just need to be more conscious of where our food comes from.  Eating locally is only part of the answer to the problems with our food system.  It surely solves some problems, but not all.

TALKING about a New Year's Resolution

I like social media.  It's a fun way to stay in contact with friends.  Since I've lived in so many places (and gone through so many years of education), I have friends all over.  Since people are so busy, social media makes it easy for me to stay up to date with what my friends are up to.  In the last few years, I've felt like I've been in contact with more people than usual.  This is good, as social connection is a key to human happiness.

Only so much can be conveyed over social media.  Sure I can see who was married and what movies my friends like.  But a lot of human communication is through tone of voice and facial expression.  Status updates do not convey feelings or emotions the way a face-to-face conversation does.  Though I feel more connected to more people now, I feel less deeply connected to my close friends.

My new year's resolution: Call a friend.

Let's be more specific. Training Peaks says not to make resolutions, but to make plans.  I plan to talk 2 friends a month.  The preferred method is via face-to-face conversation.  This is pretty easy for my friends in California.  For those far away, I plan a video chat.  So friends, do not be surprised if I randomly video call you.  I know that a recent NPR report said that many were uncomfortable with video chat, because the person you are calling may be having a bad hair day.  But, the expert reminded us: "Your parents, maybe your siblings or a very close friend, the people that you really want to video-call with are probably people that wouldn't mind if you're having a bad-hair day. They've seen your bad-hair days. They don't care."

I know that 2 friends a month seems like a small task, but think of how many of you I actually spoke to in a real face-to-face conversation in the past year.  Want to get the year started off to a good start?  Be one of the first to help me with my plans.  Contact me and let me know when you are free.  You can find me on Facebook, Gmail, Google+ (hangout preferred!), or your other favorite social media.

Why you don't need fasting blood work

For a long time, the "guidelines" of medicine have insisted that we get fasting cholesterol levels on patients.  Why?  The theory was that we really need to target LDL ("bad") cholesterol, and the only way to find out "exactly" what your LDL was required getting a fasting blood sample.

There are many holes in this guideline.  First, the "lipid hypothesis" has mostly blown over.  Many studies have shown that you can treat lipids really well, but do nothing for the patient.  We can target that LDL to the lowest level, but still not affect whether the patient gets a heart attack or stroke.  A great overview is on this is in this podcast, from the guys at TEC.

Secondly, you don't really need an LDL to make a general risk assessment of how high risk a patient is for a heart attack.  As you can see from this chart, you really only need to know your total cholesterol and HDL ("good" cholesterol) to get an idea of your risk.  The LDL doesn't matter that much.

Now we have a great new study published in the Archives of Internal Medicine, showing that it does not really matter if patients fast or not.  The cholesterol levels do not change appreciably enough that it would affect treatment.  The related commentary falls a little short of advocating for docs to stop doing fasting cholesterol tests, but says that doing so is reasonable for most patients.

Finally, I often had patients come to my office at 2 pm, having fasted all day, just to get their cholesterol test.  This is just inhumane.  I do not feel good when I fast, and I don't think my patients do either.  Doctors need to start accommodating patients instead of following guidelines.

One more thing.  Does your doctor say you need a fasting blood sugar to screen for diabetes?  Nope.  We can screen for that with an A1C test, which doesn't require fasting.

Doctors: Let's start eating like we want our patients to eat

In my new viewpoint in JAMA, I propose that at all the meetings health professionals go to, there should be healthy food.  This may sound like a simple idea, but it has yet to materialize.  Physicians get "mad" at patients for not eating a healthy diet, and then go to a lunch seminar and eat roast beef and cookies.

It is hard to eat healthy in today's America.  Even when I'm at meetings, it's difficult to not take (at least a piece) of a cookie, when they are offered for free.  So let's make it easier by not providing junk food (cookies, soda, chips) at meetings.

Then we can make sure our meals are consistent with the dietary guidelines: they should be mostly made up of vegetables.  Once we do that, we can help our communities eat healthier.  Let's clean up our own eating habits and set an example for our community.

Politics and the Family

In tonight's Republican Convention speeches, we saw two different takes on American culture: the Strict Father and the Nurturing Mother.

For those who follow my blog and politics, you know that I am a fan of George Lakoff's family model of politics.  Briefly, it says that most Americans have two mindsets: a father model, where respect and obedience are of primary importance; and a mother model, where nurturing and love are primary.

We saw both of these models tonight.  Ann Romney spoke mostly about love.  She spoke about struggling families and the love in their relationship bringing them through hard times:

And I want us to think tonight about the love we all share for those Americans, our brothers and sisters, who are going through difficult times, whose days are never easy, nights are always long, and whose work never seems done.

This is exactly the progressive mindset that Lakoff describes.  The interesting point is that Lakoff's research shows that talking in this nurturing model makes people think more progressively and more likely to vote Democratic.  She finished with this:

I said tonight I wanted to talk to you about love. Look into your hearts.

This is our country.

This is our future.

These are our children and grandchildren.

Gov. Christie was next.  He spoke in a different model:

 [My mother] said to always pick being respected, that love without respect was always fleeting — but that respect could grow into real, lasting love.....Tonight, we choose respect over love.

This is Lakoff's father model, which gets people to think like a Republican and vote more conservatively.  Clearly, Christie is more in tune to politics that Ann Romney.  Romney's speech could actually persuade many women to vote Democratic.  But even Christie showed some of the motherly frame of mind:

Instead, the people of New Jersey stepped up and shared in the sacrifice.

This "shared sacrifice" terminology is something that Obama uses regularly to talk about progressive agendas.  Sharing brings up the progressive mindset.  Sharing leads to policies that promote the greater good: health care for all, unemployment assistance, well funded public education, and quality infrastructure.

My parents instilled in me the importance of love more than respect.  I'm not saying that I wasn't taught respect.  Again, all of our minds have both typologies.  But, the strongest underlying theme in my family was that love and nurturing were more important than obedience and respect.  Love and nurturing leads to respect, rather than Christie's claim of vice versa.

The love in my family led me to believe in progressive values.  How has your upbringing made you think about politics?  Have you thought about these mindsets before?

(And thank you to tonight's speakers for possibly convincing a few more people to think like Obama.)