Food processing has a long history. Even in prehistoric times, people were using salt, fermentation techniques, and sun-drying to preserve food. Basic cooking methods are a form of food processing, serving to lengthen the lifespan of raw ingredients.
Commercial food processing emerged in the mid-nineteenth century. The industry leveraged our ancestors’ logic to make food more accessible for growing populations — greatly improving food availability, affordability, and shelf life.
But as this industry has evolved, the nutritional value of ultra-processed foods (UPFs) has been repeatedly called into question. Studies consistently link high UPF consumption with an increased risk of a range of chronic health conditions, such as cancer, diabetes, and heart disease.
It’s well known that eating a balanced diet with plenty of fruits and veggies promotes better physical health — and a growing body of research offers insight into how nutrition can affect our moods. Some of that research points to a potential impact of UPFs: a negative impact on our mental health.
The Food and Agriculture Organization (FAO) created the NOVA classification system to organize foods based on their level of processing. These groups are based on factors like ingredients and processing techniques — and include:
• Foods that are unprocessed or minimally processed with methods like drying, boiling, or pasteurizing
• Foods processed with culinary ingredients like butter, oil, and salt
• Processed foods, which “retain the basic identity and most constituents of the original food,” like canned or bottled foods, breads, and natural cheeses
• Ultra-processed foods, which are made primarily from industrial ingredients — and often contain preservatives and additives like stabilizers, artificial colors, and flavoring
The techniques and ingredients used to manufacture UPFs make them easy for companies to produce at scale. This makes UPFs inexpensive, convenient, and durable.
That’s why UPFs are so universal today, making up an estimated 57.5 percent of the average American diet. Some of the most common culprits are soft drinks, packaged snacks and baked goods, breakfast cereals, processed meats (like hotdogs and chicken nuggets), and some frozen packaged meals.
The additives in these UPFs have a negative impact on our gut microbiome. Researchers have found strong connections between gut health and brain function — with studies showing that bacteria imbalances can lead to low moods and depression.
But the ingredients in UPFs aren’t the only things threatening our mental health. What’s left out is just as significant. UPFs tend to prioritize taste, price, and transport stability over nutritional value. This makes them generally high in saturated fat, added sugar, and salt — while providing few vitamins, minerals, or macronutrients.
“We really are what we eat,” says Marni Alexander, a licensed psychotherapist and nutritionist. “Just as our bodies are reliant on essential vitamins and nutrients, a lack of crucial ingredients will impact our energy levels and feelings of well-being.”
So can we eat our way to better mental health? The experts say that limiting your intake of UPFs is a great start — but there are also nutritional choices you can make to ensure that you’re keeping both body and mind in sound shape.
There’s truth to the idea of “trusting your gut.” It has a direct line of communication with our brain — and a strong influence over our emotions, feelings, and moods.
This is because healthy gut bacteria produce hundreds of neurochemicals that our brains use to regulate processes like memory and mood. When the microbiome’s balance is out of whack, it can affect our behavior and anxiety levels, and trigger low moods.
Avoiding UPFs helps keep your gut in good form — but it’s also important to get enough:
• Fiber, for instance from whole grains and legumes
• Probiotic-rich foods like plain yogurt (but look out for added sugar)
• Fermented foods like kimchi, tempeh, and sauerkraut
“Proteins are responsible for more than we might imagine,” Alexander explains. She says that while amino acids are necessary for muscle growth and energy, they also build our mood-regulating neurotransmitters.
Research confirms that getting enough protein improves brain, psychological, and social function — so make sure you’re eating protein-rich foods like:
• Meats such as poultry, seafood, and lean red meat
• Legumes, nuts, and seeds
• Eggs with the yolk
Fats are crucial to our health. They help the body absorb vitamins and minerals, ensure good cell function, and aid with a range of processes from blood clotting to muscle movement. Of course, some types of fats are better than others — particularly unsaturated fatty acids.
For instance, studies have found that omega-3 fatty acids may be useful in the treatment of depression and other mental conditions, because they support healthy brain function and act as an anti-inflammatory agent.
Some of the best sources of omega-3 fatty acids are:
• Fatty seafood like mackerel, salmon, and oysters
• Flax seeds, chia seeds, and hemp seeds
• Walnuts and soybeans
• Some plant oils like canola, flaxseed, or soybean oil
Cruciferous vegetables (such as broccoli, brussels sprouts, cauliflower, kale, arugula, radishes, and turnips) are some of the most nutrient-rich foods on the planet. Many studies show that a high intake of these greens offers a host of health benefits — from better immune system function to a lower risk of chronic disease.
Research suggests that cruciferous vegetables may also support our mental health. They contain a plant-based compound called sulforaphane, which lowers inflammation associated with depression. They’re also good sources of B vitamins, magnesium, zinc, and selenium — all nutrients that may have a role in regulating mood.
If you need guidance in maintaining the best diet for your physical and mental health, you can reach out to our team at Carbon Health. Establishing care with a primary care doctor is a great way to stay on top of nutrition, for long-term well-being.
Carbon Health’s medical content is reviewed and approved by healthcare professionals before it is published, but it is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Talk to your healthcare provider about questions you may have regarding your health or a medical condition, and before making changes to your healthcare routine.