I think it’s safe to say that we all seek optimal cognitive function. Who isn’t game to think clearly, have a great memory, focus whenever you wish, make decisions easily, and more? Fuel yourself appropriately and you may certainly find that your cognitive function improves.
 
Cognitive function refers to mental processes involved in the acquisition of knowledge, manipulation of information, and reasoning. Cognitive function includes the domains of perception, memory, learning, attention, decision making, and language abilities.
 
It is important to recognize signs of cognitive decline, such as: 

• Being slower at normal tasks  

• Trouble retaining current information

• Feeling overwhelmed with new information  

• Difficulty focusing  

 
These and other related issues do not mean you will develop Alzheimer’s or dementia in the future — but they do indicate your brain needs support. And you are never too young to start protecting your neurological function. 

Alzheimer’s Disease
Alzheimer’s Disease (AD) is a neurodegenerative disease and the leading cause of dementia worldwide. AD develops as a result of multiple factors:

• Aging

• Apolipoprotein E (APOE) ε4 gene

• Family history

• Mild cognitive impairment (MCI)

• Cardiovascular disease risk factors (e.g. smoking, obesity in midlife and diabetes, midlife hypertension)

• Lower education

• Gut microbiota

 
According to the National Institute on Aging, mild Alzheimer’s Disease is often diagnosed when these symptoms appear:
 

• Memory loss that disrupts daily life

• Poor judgment, leading to bad decisions

• Loss of spontaneity and sense of initiative

• Losing track of dates or knowing current location

• Taking longer to complete normal daily tasks

• Repeating questions or forgetting recently learned information

• Trouble handling money and paying bills

• Challenges in planning or solving problems

• Wandering and getting lost

• Losing things or misplacing them in odd places

• Difficulty completing tasks such as bathing

• Mood and personality changes

• Increased anxiety and/or aggression

 
Signs of advanced AD include forgetting long-term memories and loved ones and impairments in completing daily activities such as feeding, toileting, and dressing. Research supports the important role of diet in prevention and improvement of AD. 

Cognitive Function
Optimal cognitive function depends on multiple factors, including efficient detoxification of toxins, anti-inflammatory therapies, and maximum antioxidant activity. Any impairments in these areas can deprive the brain of nutrition, fuel neuroinflammation (inflammation inside the brain), and damage neurons and brain cells.
 
Your brain is particularly vulnerable to a wide range of common toxins that you are exposed to daily. Some of the biggest culprits include heavy metals such as lead, cadmium, and mercury that show up in our food, water, and surrounding environments. These toxic metals can find their way into your brain and nervous system, trigger neuroinflammation, and harm your cognitive function. Research shows a close link between toxic heavy metals and Alzheimer’s disease and dementia. These toxins can damage your brain in several ways:

• Increase the buildup of beta-amyloid plaque in the brain, a hallmark of AD

• Promote the buildup of tau proteins, also shown to harm brain cells   

• Disrupt essential minerals for brain health  

• Interfere with neurotransmitter production  

• Trigger the “alarm protein” galectin-3, which, when overexpressed, causes neuroinflammation  

Neuroinflammation
Neuroinflammation is a major contributory factor to cognitive decline. When the body is under stress, galectin-3 signals your immune system to produce inflammation as a response to threats. However, many times, this inflammation cannot turn off on its own, and it ends up harming the brain in numerous ways, such as:

• Destroying brain cells  

• Increasing oxidative stress and damage  

• Triggering brain fog and memory loss  

• Disrupting focus and attention  

• Increasing risks of dementia and Alzheimer’s disease  

 
In fact, researchers now theorize that galectin-3 plays a key role in AD and that blocking it may counteract the formation and progression of this devastating neurological disease. Studies show that AD patients have much higher levels of galectin-3 than healthy people.
 
Alzheimer’s Disease & Blood Sugar Regulation
The brain is an obligate glucose user. In AD, the brain is unable to use glucose normally, causing hypofunction of 20% to 40% in key areas of the brain responsible for the symptoms in AD. AD is referred to as type 3 diabetes, a form of brain insulin resistance. In this case, ketones may provide an alternative energy source for the brain with prominent insulin resistance. Brain ketone uptake is not altered in AD or mild cognitive impairment. Too early to say, but it may be that consistent intake of medium chain triglyceride (MCT) oil, a nutritional source of ketones, helps stabilize cognition in AD patients, particularly in mild to moderate disease. Animal studies have reported ketosis to be linked with improvements in cognitive function.
 
Protein Pump Inhibitors (PPIs) & Memory/Dementia
Mounting evidence demonstrates that the use of PPIs can contribute to dementia. In the ARIC trial, participants who used PPIs for more than four years from mid-to-late life had a higher risk of developing dementia later in life compared to non-users. Why this connection? More research is needed, but potential pathways include impaired amyloid metabolism, vitamin B12 deficiency (a consequence of PPI usage), and an altered gut microbiome. Vitamin B12 supplementation may help prevent or even reverse cognitive decline.
 
Alzheimer’s Disease & the Gut Microbiome
Gut microbial abundance & diversity may impact the brain via neurotransmitters and neuromodulators like serotonin, kynurenine, catecholamine, etc. as well as amyloids. Strongly postulated that AD may begin in the gut and is closely related to the imbalance of gut microbiota. AD is linked to depression & nutrient deficiencies.
 
Antioxidants & Cognitive Health
A 2023 systematic review and meta-analysis concluded that low blood carotenoid levels may be a risk factor for developing mild cognitive impairment and dementia. Participants with healthy brain tissue had substantially higher levels of lutein, zeaxanthin, retinol, lycopene, and alpha-tocopherol. Polyphenols, as a powerful antioxidant, can also play an essential role in the treatment of oxidative stress and neuroinflammation-related diseases.

The MIND Diet
Research demonstrates that adherence to the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet, which is high in carotenoids, specifically lutein & zeaxanthin, is associated with better cognition and reduced risk of cognitive decline. In addition to dietary sources, research also indicates that supplementation is effective. A 2017 randomized placebo-controlled trial involving participants with a mean age of 73.7 found that taking a lutein zeaxanthin supplement improved cognitive function, including memory and executive function. Later, a 2022 randomized, double-blind, placebo-controlled trial involving 90 people aged 40-75 with self-reported cognitive dysfunction found that lutein zeaxanthin supplementation resulted in improvements in visual learning and visual episodic memory after six months.
 
The MIND diet encourages a predominantly plant-based nutritional pattern consisting of leafy green vegetables, other vegetables, berries, nuts, whole grains, and legumes and limiting amounts of processed sweets, fried foods, and cheese. Compared to the Mediterranean and DASH diets, the MIND diet plan specifically emphasizes berry consumption and the integration of leafy green vegetables into most meals.
 
Aim for:

• 3+ servings a day of whole grains

• 1+ servings a day of vegetables (other than green leafy)

• 6+ servings a week of green leafy vegetables

• 5+ servings a week of nuts

• 4+ meals a week of beans

• 2+ servings a week of berries

• 2+ meals a week of poultry

• 1+ meals a week of fish

• Mainly olive oil if added fat is used

 
Limit:

• Less than 5 servings a week of pastries and sweets

• Less than 4 servings a week of red meat (including beef, pork, lamb, and products made from these meats)

• Less than one serving a week of cheese and fried foods

• Less than 1 tablespoon a day of butter/stick margarine

 
Fats & Brain Health
The brain is rich in lipids and lipid dysregulation is thought to underlie several cognitive disorders. Lipids, especially phospholipids are the main component of neuronal membranes and are necessary for the structure and function of neurons in the brain. Micronutrients such as vitamins and minerals are also important for the maintenance of brain function. Insufficiency of these nutrients leads to brain dysfunction. Phospholipids—including phosphatidylcholine, phosphatidylserine, and plasmalogen—are efficient in alleviating cognitive impairment during aging.
 
Supplementation of omega-3 fatty acids, phosphatidylserine, vitamin B complexes, and flavonoids—whether individually or in combination—slow brain atrophy and cognitive decline, and reduce the risk of age-related neurodegenerative diseases. Docasahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are the most abundant omega-3 fatty acids. The high levels of unsaturation of EPA and DHA endow them with the ability to affect membrane fluidity, which is necessary for synaptic plasticity. Furthermore, EPA and DHA modify neurotransmission, reduce neuro-inflammation and promote neuronal survival and neurogenesis. DHA is crucial for neurogenesis and neuronal migration, synaptogenesis, fatty acid composition of membranes, and fluidity, which affect the neurotransmitter systems, particularly the visual system. Higher plasma EPA or DHA concentration is associated with less atrophy in the hippocampus and amygdala, as well as a lower incidence of AD. DHA supplementation at 2 grams daily has been shown to improve the cognitive function of patients with mild cognitive impairment.
 
A study with over 6,000 women reported that high amounts of saturated fatty acids were associated with worse cognitive and verbal memory trajectories. In contrast, higher monounsaturated fatty acids was related to an improved trajectory. A 2023 review observed an association between a high saturated fat, high refined carbohydrate diet and impaired cognitive function. Consumption of a high-fat diet stimulates the hippocampus to produce a neuro-inflammatory response to even a mild immune challenge, resulting in memory deficits.
 
Caffeine & Cognition
The majority of studies suggest a positive association between caffeine and memory in the adult and elderly population, but not in children. This research looks a bit stronger in females than males. One trial reported a low dose of caffeine (65 mg) decreased simple reaction time and increased the coding of new information. In a different study, findings indicated that light consumption of alcohol (<11 g/day) and coffee (<2.8 cups/day) might be independently associated with a reduced risk for developing cognitive deficits compared to abstinence. Cognitive benefits of tea consumption seemingly increase with daily dosage. While there is suggestive evidence from clinical studies that caffeine is neuroprotective against dementia and possibly AD, all in all, current literature seems to support the notion that caffeine/coffee acts as a cognitive normalizer instead of a cognitive enhancer.

Nutrition & Lifestyle Strategies for Optimal Cognitive Health

• MIND Diet

  • Rich in phytochemicals – polyphenols, lutein, zeaxanthin, flavonoids

  • Berries, dark leafy greens, spices, cocoa

  • Limited added sugars

  • Healthy fats rich in monounsaturated fatty acids & omega-3 fatty acids

  • Sufficient protein

  • Micronutrients - B vitamins, Vitamin D, Iron

• Adequate hydration

• Avoid smoking

• Be active – achieve regular physical activity

• Consider intermittent fasting

• Engage in ‘brain’ activities

• Seek a mental health balance/social connectedness

• Achieve &/or maintain a healthy body weight with adequate lean muscle mass

• Aim to get 7-8 hours of sleep nightly

 
Foundational Supplemental Support for Optimal Cognitive Health

• Omega-3 fatty acids – 2000 mg daily

• Vitamin D – 1000-5000IU D3 daily

• B vitamins -

• Magnesium – 200-400 mg daily

• Probiotics/prebiotics

 
Additional Supplements to Consider for Optimal Cognitive Health
Not meaning anyone would take all of these, but perhaps worth further investigating if one or two of these may be of interest for additional cognitive support.

• Lion’s mane

• Choline

• MCP

• Honokiol extract

• Ashwagandha

• Curcumin

• Ginkgo biloba

• Saffron

• Resveratrol

Wishing you all health and happiness in 2024!

Warm regards,

Natalie