Have you tried doing brain-intensive work while experiencing headaches, brain fog, joint pain or unstable blood sugar? If so, you likely noticed a decline in your overall cognitive performance. This may be due to oxidative stress, often caused by an imbalance between free radicals and antioxidants within your body.

Free radicals help fight off toxins in your body. However, when there is a higher level of free radicals than antioxidants, the free radicals start damaging DNA, proteins and fatty tissues. In the short term, you experience signs and symptoms such as headaches, fatigue and brain fog that impact your cognitive performance at work.

Something that would typically take an hour may take way longer. You have a more challenging time concentrating. You feel mentally stuck with a lack of clarity. When it comes to relationships, you may quickly get irritated and agitated. As a senior leader, these little incidents compound over time resulting in a significant loss of time and money.

Your cognitive health has a lot to do with how you perform at work. As the founder and CEO of Optimyzed Brain, I teach and consult senior leaders to optimize their cognitive performance through a holistic, science-based actionable process. So what do you do when experiencing oxidative stress?

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While it’s impossible to eliminate oxidative stress, you can minimize it. The most straightforward action is to increase the level of antioxidants in your body. Antioxidants help neutralize free radicals to become less reactive in your body. In this article, you will learn about seven types of antioxidants and how you can obtain them through natural sources. I am a proponent of getting nutrients first and foremost through natural sources so the body can metabolize the correct dosage.

Lycopene is a pigment that gives fruits and vegetables their red colors. The highest source of lycopene can be obtained from sundried tomatoes, tomatoes, watermelon and pink grapefruit.

Lutein is a pigment in fruits and vegetables that gives them a yellow to reddish color. Surprisingly, lutein is more concentrated in leafy greens. The chlorophyll in these greens overpowers the lutein color — hence these appear greener. Lutein isn’t made in your body, so you’ll need to incorporate fruits and vegetables that have this antioxidant. The best source for lutein is kale, swiss chard and spinach.

Beta carotene gives plants their red, orange and yellow color. Beta carotene is unique because the body can easily convert it into vitamin A. You can best obtain beta carotene through carrots, sweet potatoes and pumpkin.

Resveratrol is a type of polyphenol. It’s found in the seeds and skin of red grapes. You won’t find this in animals, as plants make this antioxidant to protect themselves against stress and infection. So your best source for obtaining resveratrol is by consuming grapes.

Coenzyme Q10 (CoQ10) is produced in the body and stored in the cell to act as an antioxidant and help generate energy. However, the production of CoQ10 decreases with age, even as early as in your twenties, and stress can cause its levels to deplete. Ensuring that you obtain CoQ10 through meals is vital. Your best source for CoQ10 is oily fish such as tuna and salmon.

Lignans are bioactive compounds that not only act as antioxidants but are also anti-inflammatory. You can get the highest source of lignans from flax seeds, sesame seeds, broccoli and brussel sprouts.

Quercetin is not only an antioxidant but also helps manage blood pressure and inflammation. Luckily, it is one of the most easily sourced antioxidants as it is present in fruits, vegetables and grains. Two of the highest concentrations of quercetin are capers and red onions. You can also source quercetin from eating apples, dark berries and grapes.

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Anthocyanins are a type of flavonoids that fight off oxidative stress and help your brain become more efficient. Anthocyanins help increase blood flow to the brain, especially in the areas related to memory and attention. They give flowers and skin of fruits a natural red, blue and purple color. You can get the highest concentration of anthocyanins from black elderberries, black chokeberries, black currants, blackberries, blueberries and mulberries.

Zeaxanthin is a powerful antioxidant found in the cells of your eyes, your skin and areas of your brain responsible for cognition and decision-making. It plays a vital role in protecting your body from harmful light waves. The highest zeaxanthin sources are spinach, pistachios, green peas, lettuce, brussel sprouts and broccoli.

Improving your nutrition for cognitive performance is the first critical step to finding success, which busy leaders often miss. Not only do you start addressing the root cause of issues such as brain fog, inflammation, headaches and unstable blood sugar, but also you power your brain to achieve targets at work.

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