At first glance, the phrase “intellectual flexibility” brings to mind someone who has no principles, but I’d like to propose that intellectual flexibility is a good thing. If you’re passionate about food, health, and nutrition science, as I am, being intellectually inflexible can be a big liability.
The dawn of nutrition science
Nutrition is a young science. Even simple concepts, such as vitamins and minerals, only gained wider understanding in the 20th century. More complex dietary puzzles still aren’t solved. We have some good ideas about how nutrition and health are connected, to be sure, but the fine details elude even the experts.
For example, we know that a plant-based diet pattern consistently is linked with lower risk of the chronic diseases that plague modern man. This includes heart disease, diabetes, stroke, hypertension, osteoarthritis, and some types of cancer. Plant-based refers to any dietary pattern that is based around eating plenty of fresh and minimally processed vegetables and fruit, legumes (beans and peas), nuts, seeds, and whole grains (brown bread doesn’t count), regardless of whether it contains modest amounts of animal foods.
The Mediterranean diet is an example of this type of eating pattern. The Okinawa diet is another example. Both of these dietary patterns are linked with excellent health, especially when compared with the processed food and meat-heavy fare typical of the American diet.
Accepting the evidence and new ideas
Although many nutrition experts agree that eating more plants is a good way to improve health, agreement begins to break down when we delve into specific dietary components. This is where the benefits of intellectual flexibility are most evident. I experienced this in my own life very recently.
I had written a newsletter about a comprehensive analysis of research on multivitamins and mortality. Previous observational research suggested multivitamins increased risk of death, and vitamin skeptics raised the alarm. This new study however, which included only controlled clinical trials—the gold standard of evidence—suggests the alarm is unwarranted. The study conclusion: taking multivitamins has no affect on risk of death due to any cause.
I wrote up the “take away” message, noting that it’s fine to take a multivitamin, it’s unlikely to harm health, but it’s not likely to help much either. End of story. Or so I thought. I received comments back from the medical editor, indicating that I had failed to mention that many people took vitamins “for energy.” I chuckled to myself and responded that vitamins don’t give people energy (unless they have a vitamin deficiency). If someone claims vitamins give them energy, it’s probably placebo effect.
My colleague pointed out a double-blind, placebo-controlled clinical trial, in which participants who received the multivitamin reported significantly greater reductions in anxiety and perceived stress compared with people who received the placebo. The vitamin recipients also rated themselves as less tired and better able to concentrate following treatment.
Maintaining my intellectual flexibility
What?! This flew in the face of everything I had ever believed about multivitamins as a harmless, yet ineffective way to alter how people actually feel. I quickly searched the medical literature, and confirmed that yes, vitamins can improve energy and feelings of well being.
One study found that participants receiving a mix of B vitamins, minerals, and vitamin C had significant improvements in mental and physical stamina, concentration, and alertness compared with the placebo group. Other placebo-controlled, blinded trials concurred with these findings.
My strongly held conviction that vitamins cannot objectively improve physical or mental well being was challenged, and I was forced to reexamine my beliefs. I concluded that I had been wrong. And I changed my opinion. That is intellectual flexibility: being open to new evidence, and the willingness to admit that previously held beliefs may be incorrect.
Are you (or your nutrition guru) intellectually inflexible?
This is just one example of intellectual flexibility, but there are many others I’ve experienced in my own life and work. Unfortunately, many self-proclaimed nutrition experts are unwilling to walk the path of intellectual flexibility.
There are vitamin D experts, who refuse to acknowledge the possibility that high, though still normal, blood levels of vitamin D may increase the risk of some types of cancer. Paleo diet pushers who, despite strong evidence to the contrary, insist that legumes harm, rather than improve health. And Atkins’ diet proponents who deny that higher intakes of meat are linked with increased risk of heart disease and cancer.
Why take your advice from a nutrition guru who is dogmatic and inflexible, and who clings to opinions about nutrition and health that have been challenged with good evidence? Doing so is a recipe for making poor nutrition choices. When it comes to nutrition science, exercising your intellectual flexibility is an important part of the learning process.