Your brain is the very essence of your being. It gives you your identity and makes you human. Likely the most important factor that impacts whether your brain is functioning optimally, or declining and shrinking, is the food you choose to eat every day.

There are a variety of foods that can injure your brain, either through worsening blood sugar control or from a direct toxic impact on your brain itself.

Let’s clarify how and why certain foods are potentially harmful to your brain.

#1: Sugar and Grain Flour

The #1 cause for cognitive decline and memory loss is abnormal blood sugar control, known as insulin resistance. The factor that has the greatest impact on blood sugar levels is sugar intake. We clearly need to avoid sugar.

Table sugar is not the only cause of abnormal blood sugar control. All sources of flour have the same impact on blood sugar as does table sugar. When you compare the impact of consuming a bowl of whole wheat flour, white flour, or table sugar, they all have the exact same impact on blood sugar levels.

The bottom line is if we want healthy blood sugar regulation, then we need to avoid eating and drinking all forms of sugar, and we also need to avoid flour in any form.

The only thing worse than eating sugary foods (cookies, cakes, candy) would be drinking sugary drinks (sodas, sweet tea, juice). Liquid sugar has a worse impact on blood sugar control than eating sugar-rich foods.

Here is a tip to avoid flour: When you see a recipe suggesting grain flour, consider using almond meal or coconut meal instead. They work really well in a variety of recipes and they won’t increase your blood sugar levels.

#2: Trans fats (hydrogenated fats)

For nearly 20 years, I have referred to these nasty fats as embalming fluid, because if you eat them, you are killing yourself. Trans fats worsen cholesterol profiles, worsen blood sugar levels, decrease brain function, stiffen your cells, and increase your risk for cancer.

To avoid them, avoid fried foods, as the oil in deep fryers is quickly converted into trans fats. You also need to read the ingredient list on any prepared foods. If you see the words “partially hydrogenated fats”, put it back on the shelf and buy something else.

#3: Foods preserved with Nitrosamines

Processed meats (such as hot dogs, sausages, pepperoni, ham, bacon, and deli meats) are commonly treated with nitrosamines (nitrates) to extend their shelf life and increase profits for the company selling them.

Not only do nitrosamines hurt your cognitive function, they’re also highly carcinogenic.

In one alarming study, rodents that were administered nitrosamines almost immediately developed insulin resistance, diabetes, fatty liver, and Alzheimer’s disease. Talk about an important discovery!

DON’T forget to read food labels, especially if you buy processed foods!

Make sure you don’t buy processed meats that are made with nitrosamines. Instead, if you buy animal protein (such as bacon), make sure it was pasture and organically raised, and that it is nitrosamine free.

#4: Foods with Pesticides

Pesticide exposure can also lead to higher risks of memory loss and dementia.

In a study of nearly 1000 adults, those with highest pesticide levels were 350% more likely to develop dementia. A scary finding, to say the least!

The biggest sources of pesticides come from:

• Feedlot raised meat and poultry
• Dairy products
• The dirty dozen fruits and vegetables (see the Environmental working group website (ewg.org for details—including dirty foods such as strawberries spinach, apples, cherries, grapes, celery, bell peppers, and potatoes).

The easiest way to avoid pesticides is to first, ensure that when you eat meat, poultry, or dairy, it is organically raised. Second, if you buy fruits and vegetables that are on the dirty dozen list, make sure you buy these items organic.

#5: Gluten

20% of people are sensitive to gluten, meaning if they eat gluten, it has the potential to initiate an auto-immune reaction, which can cause injury to the brain. If you have unexplained medical problems (in particular problems with your gut, or other chronic issues such as brain fog, diffuse joint achiness, or thyroid issues), I strongly recommend that you either try an elimination diet and avoid all gluten products for at least one month, or have gluten antibody testing performed with your own physician.

Keep in mind, nobody needs gluten to live. We can easily meet all our nutrient needs without it. All of us likely would benefit from giving up eating bread, crackers, and products with grain flour.

#6: Foods prepared with sweeteners (such as Splenda)

I aim to avoid all the chemical sweeteners. The one I avoid the most urgently includes everything made with Splenda (Sucralose). Splenda is chlorinated sugar. It tastes sweet but it isn’t absorbed, so you can consume it without gaining any calories—sounds terrific, right? Sadly, it isn’t that simple. Turns out the chlorinated sugar has been shown to kill the healthy bacteria in your gut. All the recent studies have shown that your gut bacteria are essential to a healthy brain, so in reality, a product that harms your gut microbiome needs to be completely avoided if you want to protect your brain.

Ideally, you should avoid all sweeteners and forms of sugars. If on occasion you absolutely have to use something, then I’d recommend either Stevia, Xylitol, or Erythritol instead.

Now that you know what foods to avoid to protect your brain, you have taken one of the critical steps to being mentally sharper, quicker, and more productive. These same steps are also terrific for your heart health and sexual function as well, and who doesn’t want that.

Now that you know what not to eat, let me share foods that are absolutely essential for a healthy brain. To name a few, you should enjoy the following more often:

• Colorful vegetables
• Omega-3 rich seafood
• Extra virgin olive oil
• Nuts
• Berries
• Cocoa
• Green tea

As a bonus, even coffee and red wine are good for your brain if you consume them in moderation, not more than 1-2 servings per day.

There are many more details in my book, The Better Brain Solution. 

I wish you the best of health!

Steven Masley, MD, FAHA, FACN, FAAFP, CNS