Wednesday, August 18, 2010

Superbad? The Problem with "Superfood" Lists

Today I hopped over to Forbes.com to review their "most stressful cities" list (and was relieved that St Louis wasn't topping another "bad" place to live list -- I think topping the syphilis list is enough). While I was there, a link to a list of "10 foods you should be eating" caught my eye. I'm always wary of such lists, and this one provided a nice reminder of why:

The list starts out with three great foods - cherries, blueberries and kiwi. All three are great choices because they are fruit and eating a lot of fruits and vegetables have been shown to decrease risk of several diseases, including cancer. The problem, to me, is that most Americans don't come anywhere near to eating enough fruit, regardless of the type. Also, the three fruits are in season for a pretty short period of time, making their cost pretty high the rest of the year. Add to that, the fact that berries tend to top lists of fruits that absorb the most pesticides, so other lists are telling you to only buy organic and you've got a major cost issue on your hands. For most people, just starting to eat 2-3 servings of fruit a day, of ANY fruit, is going to be a big step.

The list then moves on to proteins -- grass-fed beef, wild salmon, flax seed and whey protein powder. While I certainly see the merit of choosing grass-fed beef over industrial beef for the reasons listed (omega-3 content being a big one, environmental impact being another), the context is missing here. Grass-fed beef is expensive and most Americans eat too much red meat of all kinds and certainly don't need beef appearing on a list of things they need more of. If you want to up your omega-3 intake, replace your meat intake with other sources of protein rich in omega-3, like fish and flax seed and aim to reduce your meat intake in general.

The list ends with dark chocolate. With overweight and obesity rates topping 60% in the US, I don't think anyone needs encouragement to eat more chocolate. Granted, the fine print suggests looking for chocolate with at least 60% cocoa content (ruling out most candy bars in the checkout aisle), but portion size and frequency of intake are big issues here and neither is mentioned.

Also overlooked in the discussion is that much of the data supporting the "superfood" concept don't come from studies of people eating those foods. The data come from studies of human cell lines or of extracts of a single component/nutrient that the food is high in. The problem with these studies is 1) that flesh and blood humans are very different from a collection of cells in a petri dish and 2) that the volume of intake needed to reach the dose given to the cells or extracted and given to humans is difficult to achieve through consumption of the food itself.

So, the cold reality is that there are no real "superfoods," just like there are no magic bullets.  It's simply a title dreamed up by magazine editors or folks who don't have a good understanding of the science linking diet and human health.

Of course, overall diet can have a large impact on chronic disease, and making simple, largely inexpensive, changes to what we eat can have big benefits.  Eating a diet rich in fruits, vegetables, whole grains, and healthy fats (like poly and monounsaturated fats); and low in red meat and unhealthy fats (like saturated and trans) will trump any collection of "superfoods" when it comes to health benefits, and it'll likely save you a lot of money along the way.

I wonder if by suggesting that people need to go spend $30 on organic blueberries and eat chocolate to be healthy we actually encourage the status quo as so few people have the ability to spend at this level and so few read the fine print of the message? What do you think? Do these lists help you make healthy choices or confirm that you are/aren't healthy already?

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