In a world that demands constant mental performance, nutrition often becomes an overlooked pillar of brain health. There are powerful nutrition strategies for brain health such as avoiding key deficiencies and leveraging smart caffeine combinations.

It’s trendy to focus on nootropic compounds, which are compounds that enhance memory or other cognitive functions; as well as brain foods such as dark chocolate, green tea, and oily fish. Though there are benefits associated with both, many individuals overlook common nutritional deficiencies that sabotage cognitive function. These nutritional deficiencies include vitamins B12, D, magnesium and iron. Vitamin B12 is essential for nerve health and the formation of neurotransmitters. A deficiency can lead to memory loss, brain fog, and even depression. Vegetarians, vegans, and older adults are especially at risk. Vitamin D, often called the “sunshine vitamin”, plays a role in mood regulation and cognitive performance. Low levels are associated with depression, cognitive decline, and increased dementia risk.

Magnesium supports 300-plus enzymatic processes in the body, many of which impact the nervous system. Deficiency can lead to anxiety, poor concentration and sleep disturbances. Iron is vital for oxygen transport in the brain. Even mild iron deficiency, which is common among women, can reduce attention span, energy and memory. Addressing these deficiencies through a well-balanced diet or targeted supplementation can dramatically improve cognitive performance.

For vitamin B12, focus on animal-based foods like eggs, dairy, salmon, tuna, sardines and organ meats (especially liver). For those that are vegetarian or vegan, fortified foods like plant milks, breakfast cereals and nutritional yeast can help, but a supplement is often necessary due to the limited plant-based sources. Vitamin D is a bit trickier to get from food alone, but fatty fish (like salmon, mackerel and sardines), egg yolks and fortified products (milk, orange juice, cereals) can help maintain healthy levels. However, sunlight (10 to 30 minutes of sun exposure a few times a week) and supplementation are often needed alongside food sources.

Studies show that up to 75 percent of Americans don’t meet recommended daily intake of magnesium from food alone. Load up on leafy greens (spinach, Swiss chard, kale), nuts and seeds (pumpkin seeds, almonds, cashews), legumes, dark chocolate and whole grains like quinoa and brown rice. For iron, red meat is one of the richest and most absorbable sources (heme iron), but chicken, turkey, shellfish (especially clams and oysters), and eggs are also great options. Plant-based sources like lentils, beans, tofu, spinach and fortified cereals contain non-heme iron, which is absorbed more effectively when paired with vitamin C-rich foods like bell peppers, citrus fruits or tomatoes. 

Caffeine paired with L-theanine is a brain fuel combo backed by science. Research shows that combining caffeine and L-theanine enhances attention, reaction time and working memory better than caffeine alone. Caffeine on its own can cause jitters, anxiety and crashes. Enter L-theanine, an amino acid found in green tea, known to promote calmness without sedation. When paired with caffeine, the result is a smoother, more sustained form of mental energy.

The synergy works because while caffeine boosts alertness by blocking adenosine (a sleep-promoting neurotransmitter), L-theanine increases alpha brain waves that are linked to relaxed focus. Students and professionals may especially benefit from a 2:1 ratio (200 milligrams L-theanine to 100 mg caffeine), which naturally occurs in matcha green tea. Alternatively, an L-theanine supplement could be paired with a morning or afternoon cup of Joe.

Alora Frederick, RDN, LDN, is an integrative and functional dietitian in Waltham, MA. She is currently accepting new patients at Johnson Compounding and Wellness for virtual nutrition appointments. Schedule a free, 15-minute, introductory call at NaturalCompounder.com/Alora.