There is no shortage of confusion when it comes to popular ideas about how certain foods and nutrition promote good or bad health. Part of this confusion stems from the fact that food is personal. How we eat is influenced by culture, personal beliefs and even religion, to name just a few factors.

For some people, ways of eating can take on the veil of a religion based more in a belief structure than on current science. Even so, selective scientific information often is used to support and promote questionable ways of eating. Fueling this confusion is a common lack of understanding of the difference between correlation (association) and causation.

Although science and belief have clashed for centuries, when a scientific fact becomes undeniable (such as Earth orbits the sun), controversy gradually resolves. Despite a great deal of scientific knowledge about the essential nutrient needs of the human body and the foods that provide those nutrients, many people still are driven by personal beliefs about what “feels right” regarding what is “healthy or unhealthy.”

QUESTION: Why does it seem like nutritionists keep changing their mind about nutrition recommendations?

ANSWER: Common public perception is that food and nutrition recommendations keep changing. Part of the confusion likely comes from the fact that many people hold themselves out as experts in nutrition to promote their beliefs about diet and health and often to sell a book or other products. When one’s livelihood relies on a position they have taken regarding the health benefits or harms of foods, it becomes almost impossible to change course even if scientific facts clearly expose problems. This is when nutrition or a way of eating can become tantamount to a religion or, even worse, a moneymaking scam.

Q: How have eating styles become more philosophical than scientific?

A: Food and folklore have been intertwined for centuries, but during the last few decades there has been a strong shift in how individuals view food. Historically, food was primarily a key component of survival itself. As society evolved, foods were chosen to provide the energy needed for hard work that required physical labor. Later, food became a symbol of economic wealth.

In contemporary society, views of food seem to have become more detached from food’s known essential functions such as providing energy and essential nutrients for growth, maintenance of health and successful reproduction. Somehow, “step one” in good nutrition (meeting essential nutrient needs) has taken a back seat to other priorities in choosing foods to consume for health.

Q: What additional factors are affecting what foods people choose to eat?

A: There are many reasons why people are choosing foods without a focus on meeting nutrient needs. Important priorities such as moving forward to becoming a more sustainable planet can change food choices. In our sustainable food decisions, it is critical to focus on obtaining adequate essential nutrients to maintain health.

The body can actually thrive for a fairly long time without an adequate supply of some essential nutrients, but this can take a serious and potentially irreversible toll on long-term health. It is important to understand that obtaining all essential nutrients is most readily accomplished by not making any one food a villain, but by consuming reasonable proportions of a variety of food.