What is a Healthy Diet Anyway?
Just looking at the surplus of dieting magazine articles and flashing weight loss advertisements on websites, it’s clear that the idea of healthy living is central to the public consciousness. But beyond hyped diets, trending superfoods, and the stigma of a high body fat index, what are some ways it is actually possible to cultivate healthier eating in your life? Let’s look at the science.
Physical weight is almost exclusively determined by the makeup of the microbiome of intestinal flora and heavily determined by the genetics lottery. This means that not a lot can be done to change how much weight a person tends to carry naturally. However, the quality and types of food that a person eats can go a long way in determining their overall health. In most cases, weight itself is not the primary issue that leads to further risk of chronic disease and death, but rather it is the quality of daily nutrition--and of course, daily exercise--that can make or break a healthy lifestyle.
With that in mind, it’s important to realize that not all food is created equally. A study published in the Lancet analyzed diets in 195 countries and came to the conclusion that the leading risk factors for premature death are poor diet and nutrition. Generally speaking, Mediterranean diets--in other words, those high in fruits, vegetables, nuts, and healthy oils like fish and olive oil--correlate to populations with higher overall nutrition. Israel, France, Spain, and Japan all have the lowest rates of diet-related disease in the world, likely at least in part due to cultural adherence to a Mediterranean-like diet that places an emphasis on seafood as its primary animal protein source.
The microbiome also plays a major role in full-body nutrition. Made up of a teeming community of bacteria, archaea, protists, fungi, and viruses, the microbiome is essential to the immunological, metabolic, and even emotional regulation of its host--us! A diverse ecology of microbes live in our organs, tissues, and biofluids and contribute to nearly all healthy bodily functions.
When it comes to diet’s effect on the microbiome, the research is still in progress. We do know that inulin--the long carbohydrate chain fiber found in things like chicory root and Jerusalem artichokes--takes longer to pass through our gastrointestinal system and promotes the growth of two helpful bacteria strains, bifidobacteria and lactobacillus. Fermented foods like kimchi, sauerkraut, and pickles all contain high concentrations of healthy microbes, too. On the other hand, fatty animal tissue like pork and other heavy meats like beef can slow and hinder helpful microbial growth. Fish and other leaner meats are better when it comes to encouraging microbiome health. Because the microbiome is responsible for so much internal regulation in the body, it’s important to foster that lively, diverse petri dish of organisms in our guts.
When eating healthy, it can sometimes feel as though the odds are stacked against us, though. Over the past 70 years, ultra-processed foods have grown to encompass the majority of our diets. A controlled trial by the National Institutes of Health showed that on a diet of ultra-processed food versus a diet of whole foods, participates actually ate more than they otherwise would, even with controls in place accounting for total calories, fats, sugar, salt, protein, carbs, and fiber.
How could this be? Scientists are still looking for a concrete answer, but there are some theories.
For one, processed diets facilitate lower production of an appetite-suppressing hormone called PYY and higher production of a hunger hormone called ghrelin. Additionally, because ultra-processed food is often softer and easier to chew, researchers believe it might be easier to eat more of it without realizing it.
But it can be difficult to get food that isn’t heavily processed.
In the United States, the dairy and sugar industries are heavily subsidized by the government, meaning that the cheapest products on grocery store shelves are often the least nutritionally viable. Added to that, the regulations placed on who is allowed to apply for and receive food stamps have become more limiting in recent years. This makes shopping for high quality nutrition not only difficult, but sometimes simply unaffordable for a lot of people. But even if there was some massive shift in global policy and all healthy produce was suddenly attainable for everyone, we would still have an issue. Under the current global agricultural infrastructure, there is not enough land use focused on healthy produce to supply the world’s current population.
To fix this systemic issue, many food producers would need to make a concerted shift away from focusing resources solely on starch and sugar production. With the deleterious health effects of malnutrition costing upwards of $3.5 trillion annually, it’s clear that change can only be a good thing.