If you're burdened with constant brain fog and anxiety, you're not alone.

As a Harvard nutritionist and psychiatrist, I've spent decades researching how anxiety affects many aspects of physical health, including immunity, inflammation, diet and metabolism.

I always tell people that food and nutrition are invaluable tools that can help us relieve anxiety, boost focus and improve overall mental health.

Here are six rules I live by for a calmer, stronger and happier brain:

1. Eat whole to be whole

I use ingredients that are unprocessed, or as minimally processed, as possible.

Vegetables, berries, unprocessed grains and legumes, for example, are great sources of fiber, which is crucial for gut health and creating environments where good bacteria can thrive.

And complex carbs, like those found in vegetables, are processed more slowly by your body. This means that eating them can help you avoid spikes in your blood sugar. A healthy metabolism is a key factor in keeping anxiety at bay.

2. Consume a variety of colors

From the dark green of broccoli and spinach to the bright yellow of carrots and peppers, eating a wide range of colors delivers a steady supply of nutrients that are essential for proper brain function — and a calm mind.

But it's not just fruits and veggies. Herbs and spices like saffron, rosemary, turmeric, black pepper and basil also bring color, flavor and anxiety-fighting properties — in the form complex substances called bioactives — to your meals.

For example, curcumin, the bioactive found in turmeric, can help manage inflammation and high cholesterol.

3. Magnify micronutrients

Vitamins B-complex, C, D and E, and minerals like calcium, magnesium, iron and zinc are all important micronutrients that can help reduce anxiety.

Iron deficiency is the most common nutritional deficiency, so one of my favorite pairings is extra dark natural chocolate and a piece of orange or clementine. Cacao is a source of iron, but since it's from a plant, the vitamin C helps for maximum absorption. That's why it's such a powerful combination.

Many micronutrients have antioxidant and anti-inflammatory properties that can protect your brain from long-term decline. They also help produce and regulate mood chemicals like dopamine and serotonin.

4. Prioritize healthy fats

Your brain is made up of 60% fat, and a steady supply of healthy fats is one of the most important factors in keeping it healthy and free of anxiety.

Olive and avocado oils are anti-inflammatory and promote good gut and metabolic health. They should be your main oils for food preparation and make up the majority of your fat intake. I avoid safflower, soybean and sunflower oils, which often contain unhealthy omega-6 polyunsaturated fatty acids (PUFAS).

But healthy Omega-3 PUFAs (the fats found in seafood, nuts, and seeds) are crucial for reducing anxiety, preventing neuroinflammation, and protecting against neurodegeneration.

5. Avoid foods that spike your blood sugar

The glycemic index (GI) measures how quickly foods affect our blood glucose levels.

So high-GI carbs like refined wheat flour, white rice and other starches can spike your blood sugar, which can mean a burst of energy followed by a crash. This boom-and-bust cycle is correlated with anxiety.

You get natural sugars from fruits and vegetables, so added sugars — which are also high-GI foods and have little to no nutritional benefit — should be kept to a minimum.

6. Find consistency and balance

To create a nutrition plan that is right for you, pursue healthy foods that fit the flavor profiles and ways of eating that you already love.

Lastly, listen to your body. If you feel cranky, irritable, hungry, or jumpy after eating certain foods, try cutting them out of your diet. If something doesn't make you feel good after eating it, it's probably not good for you.

Uma Naidoo, MD, is a board-certified Harvard nutritional psychiatrist, chef, nutritional biologist, and the author of "This Is Your Brain on Food" and "Calm Your Mind with Food." She is also the founder of the first and only hospital-based Nutritional and Lifestyle Psychiatry Service in the U.S., at Massachusetts General Hospital, the original and largest teaching hospital at Harvard Medical School. Follow her on Instagram.

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