The history of nutritional science is short. Short because it hasn’t been around very long. Nutrition advice is easy to find today; it’s promoted by countless experts, whether it’s in a new diet trend, promoted by influencers, and a variety of “coaches”. Despite the attention the industry gets and most of these experts agree on some basics the information widely varies to the point that it’s difficult to find nutrition experts that can agree on basic ideas.
This is fueled by the fact that it is challenging to eat healthy in America, and most people are looking for a solution to shed weight. Weight gain is often viewed as a problem with the individual rather than looking at the systemic reasons weight gain is so common.
Everyone knows it takes effort and time to find food that doesn’t have added ingredients. For example, basic orange juice is filled with flavor packs and additives to make juice that has been in a container for over a year taste like orange juice. The additive process for orange juice is actually marketed as “Vitamin C” which is one of many concentrates that alter the beverage.
It’s easy to manipulate consumers into radically different diet trends, in part because nutritional science isn’t as advanced as it appears to be. To understand the confusion that sends dieters down different (and usually unsustainable) diet paths, it’s key that there is little research to support any diet pattern or trend.
The first nutrient, Thiamine, was isolated in 1926 which led to about fifty years of vitamin discovery and the ability to isolate vitamins to treat disease. The successful isolation of Vitamin C happened 200 years after lemons were used to treat scurvy on a ship. Still, the idea of using concentrated Vitamin C in orange juice is perceived to boost immunity and prevent scurvy. Most vegetables contain more Vitamin C than citrus, yet we reach for a glass of orange juice at the onset of a cold.
Fortified foods with added concentrates of Vitamin C, calcium, iron, and other minerals became standard during the Great Depression and WWII, when malnutrition was a real concern. However, most first-world countries haven’t been threatened by food shortages since that era but almost all staple foods are fortified. The purpose of fortification shifted from disease treatment to prevention when there wasn’t a pressing need for food fortification.
In the 1970s research became focused on preventing heart disease. Even though other research at the time implicated excess sugar as a factor in heart health, cancer, and dental diseases a small study won the attention of policymakers that put forth fat and cholesterol as the main contributing factors. In 1977, the US Dietary guidelines stated that a low-fat, low-cholesterol diet was necessary for heart health. This ushered in the age of margarine and ultra-processed foods that were labeled low-fat and perceived as healthier despite the Nutrition Board and other institutions stating that there was not enough evidence to make a connection between fat and heart health. According to the BMJ:
“Some interpret these controversies as evidence of industry influence, and others as natural disagreement and evolution of early science. More relevant is that both the dietary fat and sugar theories relied on a nutritional model developed to address deficiency diseases: identify and isolate the single relevant nutrient, assess its isolated physiological effect, and quantify its optimal intake level to prevent disease.”
Through the 1970s-1990s, heart conditions decreased, but other diet-related diseases such as diabetes, cancer, and obesity, increased. The rise of these threatening diseases and chronic conditions was treated in the nutritional model the same as before – by looking at deficiencies and supplementing.
Today, much of the research we have connecting diet to health outcomes is variable and not thorough enough to get definitive diet answers. Improved technologies like genetic testing have been a leap forward but are still not able to provide clear outcomes that can be applied broadly.
The research we have today does tell us that, “a focus on total fat, a mainstay of dietary guidelines since 1980, produced little measurable health benefit; conversely, nutrient-based recommendations for specific foods such as eggs, red meats, and dairy products (eg, based on dietary cholesterol, saturated fat, calcium) belied the observed relations of these foods with health outcomes.”
Many nutritionists and fitness fanatics still adhere to calorie counting and macro tracking, concepts that were taken from a mid-twentieth-century scientific outlook. Even the fact that we call it “nutritional science” points to the cultural outlook that food is an engineered science that can both cause or cure disease instead of just food. This mindset creates “silver bullet” foods like when wheatgrass shots were popular; and simultaneously villainizes basics like eggs. This scientific approach to food, which is heavily manipulated by marketing and outside interests puts a spotlight on each new diet trend while ignoring the last trend that didn’t work.
