You know fried food and processed junk don’t make you feel good: When you’re low on energy and dealing with a stomach ache after eating them, it’s not too much of a shocker.

But if you’re nearly falling asleep at your desk and not able to think clearly after finishing a healthy lunch, what gives? Sometimes instead of giving you fuel, the most nutritious foods cause a serious case of brain fog. And here are five that could be responsible for your afternoon slump.

Fermented Foods

Table-with-teas-in-carafes

Fermented foods have been proven time and time again to be one of the best options to keep your gut health in check, but when it comes to your brain, they might not be on your side.

Your body produces histamines naturally in response to allergens, and functional-medicine expert Dr. Will Cole, DC, says if you’re intolerant to them, that could mean trouble when you eat histamine-rich foods — aka all that kombucha, sauerkraut and kimchi. “Histamine intolerance is basically an allergic reaction without the allergen, sometimes called a ‘pseudoallergy,’” he writes.

“The typical symptoms of histamine intolerance are similar to allergic reactions, but also go beyond your typical sneezing.” And one of the most common? All that fogginess in your head.

Eggplants

If you have leaky gut — which involves gastrointestinal problems like gas, bloating, and inflammation — there’s a chance it could be messing with your brain, too: “If leaky gut is inflaming the brain, this may cause depression or brain fog, thanks to decreased nerve conduction,” writes functional medicine Datis Kharrazian, PhD.

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If you eat certain foods that exacerbate the problem, making your symptoms worse, you might experience plummeting energy levels and brain fog. And one of the worst foods for leaky gut? Eggplants, which have high amounts of lectins, a type of protein known to worsen the condition.

Avocados

Is there anything better than starting the day by smearing a creamy green avocado over a piece of toast? While they’re a great source of vitamins and healthy fat, they’re also considered a histamine-rich food, according to Dr. Amy Myers, MD. That means just like fermented goodies, they could bring on brain fog, making it really hard to get through your day.

Potatoes

Potatoes-and-fries-on-a-table

Potatoes are one of the most nutrient-dense foods on the planet with just one spud containing an impressive amount of vitamins and nutrients, including vitamin C, magnesium, protein, and vitamin B-6.

Unfortunately, they’re one of the types of food that can lead to candida overgrowth, which occurs when the candida — a type of fungus — overproduces and causes health issues.

According to Amy Myers, MD, candida thrives on sugar, and since potatoes and other starchy veggies break down in your body as sugar, they’re not making matters any better. Unfortunately, one of the many symptoms that overgrowth causes is brain fog. “Once their candida overgrowth is eliminated, their brain fog clears, their memory improves, and they feel as sharp as ever,” she writes.

Whole Grains

You know white rice and bread aren’t the best choices for staying healthy, but whole grains like brown rice, quinoa, and oats are good to go, right? According to functional and integrative medicine expert Dr. Frank Lipman, MD, even those super-nutritious choices could be a problem if you have a carbohydrate intolerance. Dealing with brain fog is just one of the signs your body could be reacting negatively to grains.


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