Tag Archive for: fried food

The Big Fried-Potato Question

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During the eight-year study, only 236 of the 4,400 subjects died; fewer than 30 per year. We don’t know what caused their deaths; one would expect it to be heart attacks and strokes but that data was not examined. The researchers adjusted the analysis for a number of variables including age, but it would have been more valuable to know whether fried-potato consumption was related to early mortality. That would give us more of an indication that there really was an increased mortality from eating french fries three days a week.


The Big Question

The big question is simply this: why are researchers from Italy examining the relationship between potato intake and mortality in a study about osteoarthritis? On the surface, it doesn’t make any sense. There was no overall strategy outlined in the reasoning for the study.

One reason they did it is because it’s open-access data: anyone can examine the data and use it for any type of analysis. All I had to do was register and I could download all the data related to any of their questionnaires including the FFQ. I’m not going to analyze the data, but I could.

The study was designed to examine osteoarthritis (OA) and the variables that are important to its prevention and treatment: “The purpose of this study is to examine people who have knee OA or are at high risk for knee OA; information will be used to better understand how to prevent and treat knee OA.” No mention of looking at potato intake and mortality.

The problem is that the authors of the study did not design the variables to examine; they had to use what was already in the study. The questions might have been different if they begin with a study to examine their research question: does potato intake affect mortality in North America? Here’s an example. The authors did not include data from potato chips in their analysis. To be fair, they couldn’t because all snacks were lumped together: potato chips, corn chips, pretzels, and other snack food. If you were starting from scratch, you would definitely include separate questions on the types of snack foods. But this is the type of problem that occurs when you don’t design the study; you take whatever is there, and maybe it works and maybe it doesn’t.


The Bottom Line

What can we gain from this research paper? Not much—it’s mostly meaningless in the real world. But we can do this: be realistic in how we prepare foods and what fast foods we choose to eat. Deep-fried foods can be a part of your diet; just make them a small, infrequent part of it. Every food can be a part of your diet as long as you control the amount and how often you eat it. Eat less. Eat better. Move more.

What are you prepared to do today?

Dr. Chet

 

Reference: Am J Clin Nutr doi: 10.3945/ajcn.117.154872

 

The Data Must Make Sense

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The data has to make sense before you do any type of statistical analysis; that’s why I always look at the mean and standard deviations. Let me explain what I found that seemed a little off in the Fried Potato Study.

The authors divided the data into quintiles based on potato consumption from less then once per month to greater than three days per week. The researchers reported 19 variables from age to calorie intake to the percentages of various diagnosed diseases in each quintile of potato intake.

I focused on the caloric intake and the Body Mass Index in each category of potato intake. As potato intake increased, the caloric intake increased 600 calories per day—from 1,150 calories per day to 1,750 calories per day. Keep in mind there are 3,600 calories in a pound, so that’s over a pound a week. In every quintile, as the potato intake increased, so did the caloric intake. That could make sense although we don’t know if the additional calories all came from potatoes.

What didn’t make sense was that the BMI for each quintile was about the same: 28.5. That makes no sense at all. If the calories increased, the BMI had to increase for each quintile. It did not. Physical activity could not explain it because those in the highest caloric intake were less active than those with the lowest potato intake. It would be wonderful if calories didn’t add up and we could eat all we want without gaining a pound. I’m sad to say it doesn’t work that way.

While the study leaves that question unanswered and many more, it still isn’t the single biggest question of all. Can you guess what it is—even without reading the study?

What are you prepared to do today?

Dr. Chet

 

Reference: Am J Clin Nutr doi: 10.3945/ajcn.117.154872

 

Fried Potatoes: Hazardous to Your Health

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The headline said: “Eating fried potatoes linked to higher risk of death.” My philosophy is that we can eat anything as long as we eat them in moderation, and I like French fries once in a while. My scientific curiosity tells me that I need to check this out. Let’s take a look at the study.

Researchers from Italy used data from the Osteoarthritis Initiative (OAI) to assess the relationship between potato intake and mortality. This is a multicenter study that recruited over 4,400 subjects from four medical centers in the North America. The eight-year study followed subjects who have osteoarthritis of the knee or are at high risk for developing it.

At the beginning of the study, data were collected on dietary intake using a Food Frequency Questionnaire. The dietary data were used to examine the relationship between potato intake and mortality rate. Non-fried potatoes were not related to increased mortality, but there was an increased risk of death for those subjects who ate fried potatoes. The risk was highest if someone ate fried potatoes more than three days per week.

Those are the results. But I have several questions of my own. I’ll cover that the rest of the week including the big question. Don’t forget: tomorrow night is the Fibromyalgia webinar; there’s still time to register.

What are you prepared to do today?

Dr. Chet

 

Reference: Am J Clin Nutr doi: 10.3945/ajcn.117.154872