A healthy relationship with food is a critical yet often ignored component of gut health. How we perceive food plays an important role in how we respond to our diet as a whole. Additionally, it may pay a role in how we respond to individual foods that we choose to avoid.
The gut-brain axis is a bi-directional relationship that plays a role in how both the brain and gut function. It posits that our gut regulates how our brain functions, and vice versa. This important concept also helps explain why it’s so important to have a healthy relationship with food.
Stress and anxiety are 2 factors that can play a major role in preventing a healthy relationship with food. As such, it can really wreak havoc on our gut health. Preconceptions on the detrimental effects of a given food may induce something called a nocebo effect in some individuals.
As a result, people experience negative effects from the belief that a food is “bad”, even if it isn’t. We know this, because you can give people an inert substance and tell them it’s something like gluten. Despite it being inert, the belief that it’s gluten induces symptoms in some people.
Demonizing foods based on the presence of a single potentially problematic component can cultivate an unhealthy relationship. It can also cause people to avoid foods they don’t need to avoid, or prevent them from identifying the actual foods that are problematic for them.
In today’s blog, we’ll discuss why building a healthy relationship with food is important for gut health using studies on the nocebo effect. To begin, we’ll discuss what the nocebo effect is as well as its cousin: The placebo effect.
What is the nocebo effect?
Most people are familiar with the placebo effect. In the placebo effect, people achieve benefit from a substance(Drug, food, etc.) even though it is inert. For example, I may give you a pill and tell you that it will help you lose weight. However, that pill is a completely inert substance that does nothing.
This doesn’t mean you won’t lose weight. The belief you will lose weight in and of itself may help you lose weight, independently of what I give you. Because of this, we use placebos in clinical research trials to tease out the actual effects of a medicine versus the perception that you will get better.
The nocebo effect is sort of the opposite of the placebo effect. In the nocebo effect, you believe that something given to you will harm you. So again, I can give you an inert substance, but tell you it’s something you believe is bad, say gluten.
When you take this inert substance, you believe you are getting gluten. Consequently, that perception drives symptoms that you associate with eating gluten.
Evidence for a placebo/nocebo effect
There is a plethora of evidence supporting both the placebo and nocebo effect. For example, one study found that telling people they were eating a reduced calorie diet caused them to lose weight even though they were eating at calorie maintenance. A control group told they were eating at maintenance had no significant weight loss. Importantly, adherence to the diet likely played a significant role.
Another study found that depressive symptoms reduced equivalently in people taking placebo, SAM-e, or escitalopram. On top of this, people’s perception of their assigned treatment played a bigger role in improvement than the actual treatment they received.
Looking at the nocebo effect specifically, one study looking at the side effects of statins found that 90% of the negative side effects induced by statins were also induced by a placebo. Furthermore, the intensity of the side effects was equivalent between groups.
A paper looking at people who received placebo treatment in endotoxemia studies found that 20% of people receiving placebo injections experienced symptoms associated with endotoxemia. This is highly relevant to gut health in that endotoxemia is believed to be a driver of the symptoms in “leaky gut”.
Finally, a study found that people with functional dyspepsia had worse symptoms when they thought they were eating a high fat diet than those who thought they were eating a low fat diet. This effect was independent of the actual fat content of the meal. It’s important to mention that people with functional dyspepsia have a form of fat intolerance.
As you can see, your perception of a food or meal can play a major role in how you respond to said meal.
How does the nocebo effect prevent a healthy relationship with food?
Unfortunately, social media is a breeding ground for misinformation about diet. Some push a narrative that meat is toxic, others that vegetables are toxic, and others that carbs are toxic.
Often times, it’s certain components of food that are toxic. Things like oxalates, salicylates, lectins, neu5gc in meat, and so on. While it’s true that some people may actually be sensitive to these food components, it’s clear that some people’s negative responses to them may be driven by perception rather than actual effect.
Just because some people have intolerances or sensitivities to specific foods doesn’t mean they are toxic or problematic for everyone. This is esepcially true when swaths of human outcome data prove otherwise. And there are tremendous inconsistencies in this space.
Some people avoid soy, wheat, nuts or dairy because they are common allergens, but eat dozens of eggs every week. Some people avoid certain foods like oils because they’re concentrated sources of nutrients(Fat) not in their natural form, but take many high dose supplements every day.
On top of this, many foods that people with gut problems purposely avoid actually have net positive benefits to the gut. One I can think of off the top of my head is soy, which is high in fiber, protein, vitamin K and the polyamine spermidine.
To build a healthy relationship with food, look at the global picture
You can find an unhealthy component in essentially every single food out there. It’s important not to judge foods based on singular components they contain, good or bad. Instead, take a global look at the food and how it fits into a healthy dietary plan.
Furthermore, you can find experimental evidence using singular datapoints that any food is unhealthy. It’s important to look at all the data and critique all of it based on the hierarchy of evidence to determine if it’s something you should worry about.
Social media influencers are terrible at this, posting mechanistic studies in rats showing harm despite either no outcome data in humans, or worse, positive outcome data in humans. Unfortunately, followers, likes, and post reach dictate social media success, not the accuracy of information.
This creates an environment where people are constantly inundated with information that can prevent a healthy relationship with food. As a result, unsuspecting readers find themselves with a progressively restrictive list of foods that they include in their diet.
If your goal is to build gut health, one of the most important things you can do for yourself is cultivate a healthy relationship with food. Often, especially for people with functional gut issues, things go the other way.
As a result, people end up on a progressively restrictive diet long term and jeopardize their nutritional status. For example, a recent case study reports on a woman with IBS who ate nothing but unfortified farina, inducing Wernicke’s encephalopathy. a neurological condition caused by thiamine deficiency.
Restrictive dieting can be a useful approach for finding food intolerances and improving functional gut problems such as IBS. But the goal of these diets should be to build a large food list after a short period of restriction. Instead, many end up with a tiny list of foods to eat ad no plan forward.
In the end, this can actually cause even more problems. In next week’s blog we’ll detail a case study where an individual spent 20 years on the restrictive dieting rollercoaster. She jumped everywhere, from vegan to Paleo, low carb to high carb.
During that time she experienced the nocebo effect multiple times, ending up underweight and malourished. She experienced emotional problems, brain fog, fatigue, weakness, and a host of other issues that were unrelenting.
After seeking counsel with a registered dietitian, she was able to expand her diet and is on her road to recovery. We’ll cover this in next week’s blog, with a follow up with her RD shortly to follow.