It happens all the time. As the Director of Nutritional, Lifestyle, and Metabolic Psychiatry at Harvard, I see patients reduce symptoms of mood disorders, lower their stress, boost their energy and alleviate cognitive impairments when they cut ultra-processed foods out of their diets and replace them with unprocessed, nutrient-dense alternatives.

Advanced technologies in food production allow our food supply to meet the demands of our growing population. But at what cost? 

Ultra-processed foods can be detrimental to our physical and mental health. Yet they now account for more than half of the calories in the standard American diet.

I try to avoid them as much as possible. And I stay away from sugary breakfast cereals in particular.  

Why ultra-processed foods are so bad for you

Ultra-processed foods are industrially produced items derived from widely grown and genetically modified crops like corn, soy, and sugar. They tend to be cheap to produce, convenient to purchase and consume, and highly palatable. 

Unfortunately, the various production steps often strip these foods of their natural vitamins, minerals and fiber. 

They have a long shelf life, which is typically achieved through added preservatives, chemicals, artificial flavors, sweeteners, and coloring, and are often unnaturally high in omega-6 fatty acids and low in omega-3 fatty acids.

This combination of artificial ingredients, sugar, high omega-6 to omega-3 ratio, and low nutritional content makes ultra-processed foods inflammatory and detrimental to the microbiome. When you eat ultra-processed foods consistently over time, it can contribute to a host of physical and mental health complications, from diabetes and obesity to depression and anxiety.

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Some of the most popular and widely consumed ultra-processed foods are breakfast cereals; snacks like chips, cookies, and crackers; salad dressings; many condiments; sugar-sweetened beverages; and commercial frozen dinners. 

These have all become staples in the American diet over the past few decades. Worse, they're often marketed as health foods, though their consumption continues to be linked to chronic inflammation and poor health outcomes.

The No. 1 ultra-processed food I avoid

Walk into most grocery stores in the U.S. and you'll find an entire aisle of cereal with jolly mascots and clever slogans grabbing the attention of consumers, especially children.

But do you know what you're really putting in your bowl every morning, and how it will — or won't — set you up for the day? 

Breakfast cereals tend to be mostly simple carbohydrates with almost an entire day's worth of added sugars. Consuming this as the first meal of the day can lead to blood sugar spikes that leave us hungry just a few hours later and more inclined to reach for a sugary snack between meals.

A carb-heavy breakfast can also lead to low energy, brain fog, and irritability later in the day.

What I choose to eat instead of cereal

An ideal breakfast is nutrient-dense and contains a balance of carbs, fats, and proteins.

Because this is hard to achieve via ultra-processed foods, I instead recommend pairing whole plant foods with your favorite clean protein and a healthy fat. A balanced breakfast with these components will power your body and mind through the morning and support healthy food choices later in the day. 

Some of my favorite brain-healthy breakfasts include: 

• Homemade chia seed pudding with a handful of blueberries and walnuts
• An egg scramble with a few veggies like spinach or tomatoes and avocado
• A green smoothie made with leafy greens, nut butter and a clean protein powder if you are having breakfast on the go!

How to cut down on cereal and other ultra-processed foods in your diet

Reducing your intake of ultra-processed foods and increasing the amount of whole foods in your diet can reverse chronic inflammation, decrease the risk of nutrient deficiencies and lead to a more balanced microbiome for improved gut health.

This last benefit is a key first step in improving mental fitness via the gut-brain connection, as well as in supporting the health of all other organ groups and overall metabolic health.

Since ultra-processed foods are everywhere in our environment, removing them entirely can seem daunting. 

If these foods are currently a key component of your diet, I recommend starting with a few swaps each day and taking it slowly. Trading your morning breakfast cereal for a healthier option is a great place to start. 

Remember, it is all about balance! Try consuming these foods as part of an 80/20 lifestyle, where 80% of your diet consists of whole, nutrient-dense foods. The remaining 20% leaves you room to enjoy life as it comes. 

Dr. Uma Naidoo is the MoodFoodMD, a Harvard-trained nutritional psychiatrist, professional chef, and nutritional biologist. She's an instructor at MasterClass and the author of "Calm your Mind with Food" and the national and international bestseller "This is Your Brain on Food."

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