Ultra Processed Foods (UPFs) - Does food science help or hurt the body?
There are so many aspects to this topic and also the social media posts I’ve been reading, I almost don’t even know where to begin. This topic speaks to the heart of what we do as nutritionists. It speaks to the heart of why I got into this field and the power of food in our bodies (good and bad). I so strongly believe this topic is one that if we don’t think clearly and objectively without coercion or profit, then RDs especially, will lose a lot of the public’s trust.
From what I’ve been reading on various posts online, there is a lot of biology conveniently omitted about this topic and sadly, lots of division created amongst practitioners.
Even just the term UPF tells us something. It’s not just processed, it’s ultra processed. You’ve heard the phrase “on steroids”. Well, ultra processed foods could be described as industrial processed foods on steroids. It’s estimated that UPFs make up 60% of most adult diets and 70% of kids. We’re talking about foods with ingredients such as bulking agents, food colors, various gums and preservatives and foods that have been through various refining and heating processing. All of these ingredients are supposed to be at a minimum on the GRAS list (generally recognized as safe). However, the GRAS list doesn’t cover long term and these ingredients although pass muster short term, they are still considered innately foreign to your gut microbes. A digestive system of the early 1900s or earlier didn’t have these compounds to interact with. It had other challenges like contaminated water, but it wasn’t interacting with a multitude of food ingredients. People ate food within a short time of harvest or purchase because shelf life was short and food spoiled. When the GRAS list was first created, the gut microbe revolution was not even a “thing”. One body of data, however, we do know is that epidemiological evidence supports a positive association between UPF consumption and body mass index and the Cardiology Society has made associations between UPFs and CVD.
In 2009 researchers in Brazil proposed it wasn’t just the nutrients or lack thereof that made processed foods unhealthy, it was the processing, which led to their developing the NOVA classification system composed of four different categories of processed foods, level four being the ultra processed. Please read the description of the four levels. The fact that our industrialized food supply has reached the point where someone felt the need to create such a classification system should in itself invite a moment of pause.
With all of this in mind, Kevin Hall a senior investigator at NIH did his own study using the NOVA classification. Hall recruited 20 healthy adult volunteers to stay at NIH for four weeks; randomly assigned to eat either UPFs or minimally processed foods for two weeks, then each group switched to the other diet for two weeks. Both groups were served twice as many calories to maintain their body weight and were instructed to eat as much as they wanted. Each diet was nutritionally matched in terms of fat, sugar, salt, fiber, carbohydrate and protein. Ta-daa— the results showed that the UPF groups ate 500 calories more per day than the minimally processed group, and were gaining weight and body fat.
So what does this mean- why did the UPF groups eat more? In the nervous system in my course we actually get into this a bit, but no doubt, foods trigger a multitude of neurological pathways that are influenced by the gut microbiome. This huge field of study which includes the downstream effects of excessive gut permeability, the entire premise of friend vs foe (immune system), along with the vagus nerve input, illustrates clear physiological connections to why UPFs play a role in chronic disease. The gut microbiome responds in some capacity to EVERYTHING we consume. Cross talk and cell signaling is constantly occurring. And not to forget the gut microbes have their own genes, far larger in number than ours. Add to this, the body burden phenomenon. One hit of a particular food or ingredient may not instigate a negative response. But, if you keep consuming daily different foreign ingredients, along with other environmental hits, and your body burden bucket gets full, then the potential for various immune responses increases. We don’t know what the threshold is that will make the immune system respond enough to produce symptoms. N=1 here. Not acknowledging these concepts is intellectually naive.
One criticism of the NOVA category is regarding the foods in the highest level four, which is the category actually labeled as UPFs. Some of these foods contain beaucoup other ingredients, but because they also may contain nutrients, many RDs argue that they should be given a pass. Let’s state the obvious here, most of us eat some form of processed foods, but please read the four categories within the NOVA system to understand the differences— it’s the category four foods that are most concerning regarding the “friend or foe” response because they contain many more added ingredients. If we gain anything out of this UPFs learning curve, is the very questionable premise that processed foods are healthy vehicles for nutrients. With this, I’m on board with the Brazil folks who devised NOVA. Yes, a certain fortified processed food may be better for some people on a budget, but we don’t really know how much of those nutrients are absorbed if the gut is impaired. The most nutrient fortified, NOVA category four UPF with multiple ingredients that give it eternal shelf life, may very well contribute to a shifted gut microbiome forming LPS endotoxins. So much evidence now associating LPS with CVD, IR, metabolic dysfunction and other systemic negative effects. So, at what cost are those possibly absorbed nutrients. Hmm, perhaps next steps, should be measuring LPS, gut profiles with people who eat many UPFs. It also speaks to reading the label and choosing foods with as few ingredients as possible—i.e. Tomato sauce: tomatoes, olive oll and salt.
Also, not mentioned is the impact of the plentiful seed oils in these processed foods. All seed oils in processed foods are ultra heated- twice. Taking an already vulnerable to oxidation omega-6 fat, heating it before purchase, then giving the okay for the consumer to heat it again, making it even more unstable is just adding fuel to the fire. I listened to a podcast recently of an RD trying to “calm the fears” of seed oils. She did acknowledge the unhealthy ratio of omega 6-to 3’s in the standard American diet but never mentioned the processing risk that omega-6s presents. The public can “handle” recommendations to restrict these foods, especially when there are many choices of healthier and flavorful fats that can withstand heat with less risk. False protecting sensibilities does not instill trust.
Finally, we shouldn’t be bragging that UPFs enable people to meet the dietary guidelines. We know the dietary guidelines do NOT address individual nutritional requirements to stay healthy, thrive and function. These are the same government organizations who have now set up a generation to develop diabetes, obesity and metabolic dysfunction at a very young age. Meet the minimal nutrient requirement to survive, but ohh, ignore the multiple downstream consequences. Our food supply was not always like this. We can do better in guiding the public.
# Derail the Shame
When I first saw this hashtag, I have to admit, I didn’t quite get it. What shame? And with who, when and why? I don’t want to be naive to what’s out there but I’m also wise enough to understand that narratives are made up to support one’s own belief system. Let’s not forget that the processed food industry is a multi million dollar industry with lots of people being paid to support a certain narrative, including RDs, MDs, scientists, politicians and health government officials.
I’ve never once in my forty years of healthcare had a patient complain of my shaming them, panicking them or overly restricting them. I’ve also worked with many eating disorders in my career particularly in the beginning when I was on a multi disciplined eating disorder team at MGH, so I get behavior risks. However, patients seek out knowledgable nutritionists to help them get well. They don’t want unwarranted hopium, nor do they want disguised and deceptive guidelines around nuancing their food choices. Yes, there ARE foods that are bad and not so healthy. I would categorize sweetened soda as bad, same with Cheez Wiz or certain frozen foods or even highly sweetened cereals. Their redeeming qualities are few, except to get your blood sugar up if you are desperate to do so, or supply an energy source, again, if you are desperate to do so. And the public knows this. UPFs could almost be categorized as emergency foods because of their shelf life, with a warning about consuming them long term. More importantly, patients don’t want me to sugar coat my recommendations. I frequently guide my patients with the phrase, “prioritize your tastes”. And, remind them that they don’t have to eat perfectly to see improvement. But, culprit and contributing ill health foods do need to be reduced and replaced with better options. All along, I am showing images of the body, digestive system etc to help connect the dots. Ultimately, patients are immensely grateful when they see their health improve and over time learn how to prioritize on their own which foods to eliminate or reduce.
And finally, what about cancer? I would be hard pressed to find any RD or nutritionist who knows enough about cancer or any other life threatening illness to confidently say that ultra processed foods do not play a role. Tell that to a cancer patient who is changing their diet to survive another year. If you say it doesn’t matter, you will lose them as a patient forever. They will find a more credible source online. The metabolism of cancer is a rapidly growing field. Prestigious researchers are putting out new YouTubes every month on this topic. Cancers are influenced by food. We know many cancers are influenced by glucose, but certain cancers are influenced by fat and protein too. Cancers create collateral paths to survive. We just don’t fully understand the role of the gut microbiome in this process, but since gut-microbes respond to food, it sure seems likely they participate. Research does show that certain gut profiles respond better to cancer immunotherapy than others. So, recommending that someone who is “all in” with revamping their eating patterns because of a debilitating or life threatening condition, and telling them that UPFs probably don’t matter, just relax and enjoy, they will say, Adios to your care. Perhaps relax and enjoy UPFs once in a while, but not regularly. I’ve had many a patient seek my consultation because of other nutritionist’s laissez faire attitudes. You can be certain a person with cancer or life threatning condition- their comfy bubble was burst with their diagnosis. They are ready for change. So, we also must be careful not to demonize people who voluntarily eat very few UPFs—food prep and all.
Of course, diet recommendations are nuanced but quality is one of the most important factors with food. Our very reputations as professionals are at risk with how we guide the public about this topic. They will quickly move on and find someone else—and I don’t blame them.
Here are several articles and papers that address a variety of viewpoints about UPFs and NOVA. I had to chuckle with the food science paper whose conclusions about NOVA are as follows,
“The NOVA system is confusing and controversial. Knowledge of food engineering and/or science must be taken into consideration if food processing is the key for food classification. NOVA could be acceptable if it were based only on health concerns, but this was not the case.”
Is not health the ultimate end goal? Seems like NOVA classification has exposed some of the risks of food science to health…hmm.
