Essential minerals, specifically magnesium and calcium, play an important role in preserving your mental acuity. Many older adults experience deficiencies in these minerals, conditions known as hypomagnesemia and hypocalcemia, which are more common than you might realize.
For instance, more than half of Americans don’t get enough magnesium daily,1 while close to 50% of the world’s population consumes inadequate levels of calcium in their diet.2 Deficiencies in calcium and magnesium undermine your cognitive abilities, leading to issues ranging from mild memory lapses to more severe cognitive impairments.
Recent research published in the journal Nutrients further uncovered how maintaining adequate levels of these minerals support your mental sharpness and overall neurological health.3
Understanding Magnesium’s Role in Cognitive Health
Magnesium is a powerhouse mineral essential for numerous bodily functions, including those of the brain. It plays a key role in energy production, particularly within mitochondria, the powerhouses of your cells. Without adequate magnesium, your brain’s ability to generate adenosine triphosphate (ATP), the main energy currency of cells, diminishes, leading to reduced cognitive function.4
As the fourth most abundant mineral in your body, magnesium is involved in over 600 enzymatic reactions.5 Additionally, it acts as a natural antioxidant, protecting your neurons from harmful free radicals and oxidative stress, which are significant contributors to age-related cognitive decline. It also regulates the activity of N-methyl-D-aspartate (NMDA) receptors involved in synaptic plasticity and memory formation.
Research indicates that higher magnesium levels are associated with better cognitive performance, suggesting that maintaining sufficient magnesium is important for preventing cognitive deterioration.6
The Calcium Connection — More Than Just Bones
Calcium, the most abundant mineral in your body, is often celebrated for its role in bone health, but its functions extend far beyond maintaining strong bones. In your brain, calcium is important for neurotransmission and neuronal excitability, processes that underpin your ability to think, learn and remember. Disruptions in calcium homeostasis lead to significant cognitive impairments.
For instance, both high calcium levels (hypercalcemia) and low calcium levels have been linked to increased risks of cognitive decline and neurodegenerative diseases like Alzheimer’s. Calcium ions act as primary messengers in various signaling pathways that support learning and memory.7
When calcium levels are imbalanced, these pathways malfunction, leading to difficulties in forming new memories and retrieving existing ones. Maintaining proper calcium levels is therefore not only essential for your bones but also for ensuring your brain continues to function optimally throughout your later years.
A signal of calcium’s importance is what happens when you don’t get enough. Your body doesn’t simply become calcium-deficient — something more complex happens. Your body maintains blood calcium levels at all costs, so when dietary calcium is low, it triggers the release of parathyroid hormone (PTH). This hormone pulls calcium from your bones to maintain blood calcium levels.
Ironically, this process leads to calcium building up in the wrong places — like blood vessels and soft tissues — while bones become weaker. This is why the common fear of dietary calcium causing tissue calcification is misguided. In fact, getting adequate calcium through your diet helps prevent unwanted calcium deposits by keeping PTH levels normal and calcium where it belongs — stored in your bones.
The Impact of Deficiencies on Cognitive Performance
The Nutrients study involved 1,220 hospitalized older adults and highlighted the detrimental effects of magnesium and calcium deficiencies on cognitive performance.8 Participants with low magnesium levels and low calcium levels scored significantly lower on cognitive assessments such as the Mini-Mental State Examination (MMSE) and the Clock-Drawing Test (CDT).
Specifically, those with both magnesium and calcium deficiencies exhibited the poorest cognitive performance, underscoring the compounded effect of lacking both minerals.9 These findings suggest that deficiencies in magnesium and calcium are not merely isolated health issues but are closely intertwined with your brain’s ability to function effectively.
The reduction in cognitive scores associated with these deficiencies points to a tangible decline in memory, attention and executive functions. Monitoring and maintaining adequate levels of these essential minerals is important for supporting your cognitive health and preventing the onset of dementia and other cognitive disorders.
Magnesium’s Protective Role
Separate research further revealed that lower serum magnesium levels are significantly associated with diminished cognitive performance in patients receiving hemodialysis, a treatment for kidney failure.10 This cross-sectional analysis found that those with low magnesium scored lower on tests of cognitive function.
Magnesium’s pivotal role in brain function cannot be overstated — it’s essential for energy production, neurotransmission and protecting neurons from oxidative stress. For hemodialysis patients, whose magnesium levels often fluctuate due to the dialysis process, ensuring adequate magnesium intake is especially important. While magnesium takes center stage in cognitive protection, phosphate also plays a supportive yet significant role in maintaining brain health.
The study highlighted that lower serum phosphate levels were associated with reduced cognitive performance, although the impact of phosphate was secondary to that of magnesium. Phosphate is integral to the formation of ATP. Adequate phosphate levels ensure that your neurons have the necessary energy to perform complex tasks such as memory formation and information processing.
Balancing Your Calcium-to-Phosphorus Ratio
It’s important to strike a balance with nutrients like phosphate, however, as both low and high levels are detrimental. In hemodialysis patients, managing phosphate levels is challenging due to the dialysis process, which removes excess phosphate from the blood. The study also noted that the use of phosphate binders, medications that help control phosphate levels, was associated with better cognitive outcomes.
This suggests that maintaining appropriate phosphate levels, alongside magnesium, is essential for supporting your cognitive functions and preventing decline. Your calcium-to-phosphorus ratio (Ca:P) is also important, and in the general population, many people consume high levels of phosphorus and low levels of calcium, which is harmful to optimal health
This is especially true if you consume a lot of animal proteins, which are rich in phosphorus. Grains and beans also contain phosphorus, as do processed foods. As a result, many people consume far more phosphorus than calcium. While an ideal Ca:P ratio is between 1:1 and 1.3:1, dairy-free and carnivore diets often result in ratios closer to 0.3:1.
When phosphorus intake is disproportionately high compared to calcium, it leads to several health issues. High phosphorus levels cause calcium to be leached from your bones to maintain a healthy calcium ratio in your blood, weakening bone structure and increasing your risk of osteoporosis.
Additionally, excessive phosphorus contributes to vascular calcification, where calcium deposits build up in your arteries, raising your risk of cardiovascular diseases. An imbalanced Ca:P ratio also increases your risk of obesity and premature aging.
Optimal Sources and Supplementation of Magnesium
Among the various forms of magnesium supplements, magnesium threonate stands out for its superior ability to cross important biological barriers, including those protecting your brain and mitochondria. For those new to magnesium supplementation, a good starting approach is to begin with 200 milligrams of magnesium citrate daily and gradually increase the amount until you notice slightly loose stools.
The reason for specifically using magnesium citrate during this calibration phase is its mild laxative properties, which help you identify your optimal dosage. Once you’ve established your personal threshold, explore other magnesium forms if you like.
It’s worth noting that blood tests aren’t particularly reliable for assessing magnesium status, as serum levels don’t accurately reflect the magnesium content in tissues like muscles and bones. The most reliable way to monitor your magnesium intake is through careful dietary tracking. Digital nutrition trackers are useful to help log and calculate your daily magnesium consumption.
While leafy greens provide excellent dietary magnesium, due to depleted soils many healthy foods have lower levels of nutrients than they used to. As a result, many people may still need supplementation to reach optimal magnesium levels. Generally, your magnesium intake should be about half of your calcium intake — so if you’re consuming 1,000 mg of calcium, your ideal magnesium intake may be about 500 mg.
What Are the Best Sources of Calcium?
The best calcium sources are from your diet, not supplements. Dairy products, including milk, raw cheese, Greek yogurt and cottage cheese, are good sources, as are cooked collard greens. Eggshells also offer a natural and bioavailable source of calcium, primarily in the form of calcium carbonate — the same compound found in your bones, teeth and nails.
What makes eggshells particularly valuable is their balanced mineral profile, containing 27 additional minerals that work synergistically with calcium to enhance absorption and utilization by your body. Unlike bone meal powder, which often accumulates toxic heavy metals (particularly from older cattle), eggshells generally contain minimal heavy metal contamination.
For those who don’t consume much dairy, consuming about 1/2 teaspoon of powdered eggshell three times daily with meals provides about 1,300 mg of calcium. If you notice any constipation, consider taking magnesium alongside the eggshell calcium for better results.
Synergistic Nutrients — Enhancing Calcium and Magnesium’s Cognitive Benefits
Maintaining optimal cognitive health involves more than just adequate calcium and magnesium intake; it requires a harmonious interplay with other essential nutrients. Vitamin D3 is a prime example of a nutrient that acts in synergy with calcium and magnesium to support brain function.
Vitamin D3 facilitates the efficient absorption of calcium from your diet into your bloodstream, ensuring that calcium is effectively utilized by your bones rather than accumulating in soft tissues where it can cause unwanted deposits.
Without sufficient vitamin D3, ideally from proper sun exposure, even a diet rich in calcium may fail to maintain proper calcium balance, leading to elevated PTH levels and the subsequent leaching of calcium from your bones.
Magnesium also plays a crucial role in regulating calcium levels, ensuring that calcium is directed into your bones where it belongs and preventing its deposition in arteries and other soft tissues. This regulation not only supports bone density but also protects against vascular calcification, which is linked to cognitive impairments and cardiovascular diseases.
Additionally, vitamin K2 — found in fermented foods like natto and sauerkraut and cheeses such as Gouda, Brie and Edam — works alongside calcium and magnesium by activating proteins that help bind calcium to the bone matrix, further enhancing bone strength and reducing the likelihood of calcium deposits in your arteries.
Together, these nutrients create a synergistic network that supports both skeletal and cognitive health. Ensuring a balanced intake of magnesium, calcium, vitamin D3 and vitamin K2 through a well-rounded diet, sunlight exposure and/or appropriate supplementation will enhance your brain’s resilience against age-related cognitive decline and maintain overall neurological well-being.
